tm2325823-5_424b3 - none

Filed Pursuant to Rule 424(b)(3)

Registration Statement No. 333-274490

PROPOSED MERGER — YOUR VOTE IS VERY IMPORTANT

Dear Shareholders of American National Bankshares Inc.:

On July 24, 2023, Atlantic Union Bankshares Corporation, which we refer to as Atlantic Union, a Virginia corporation, and American National Bankshares Inc., which we refer to as American National, a Virginia corporation, entered into an Agreement and Plan of Merger, as it may be amended from time to time, which we refer to as the merger agreement. Under the merger agreement, American National will merge with and into Atlantic Union, with Atlantic Union continuing as the surviving corporation, which we refer to as the merger. Immediately following the merger, American National Bank and Trust Company, a national banking association and wholly owned subsidiary of American National, will merge with and into Atlantic Union Bank, a Virginia chartered bank and wholly owned subsidiary of Atlantic Union, with Atlantic Union Bank continuing as the surviving bank, which we refer to as the bank merger and, together with the merger, as the mergers.

If the merger is completed, each share of common stock, par value $1.00 per share, of American National, which we refer to as American National common stock, excluding certain specified shares owned by Atlantic Union or American National, that is issued and outstanding immediately prior to the effective time of the merger, will be converted into the right to receive 1.35 shares, which we refer to as the exchange ratio, of common stock, par value $1.33 per share, of Atlantic Union, which we refer to as Atlantic Union common stock, with such shares referred to as the merger consideration.

Although the exchange ratio is fixed, the market value of the merger consideration will fluctuate with the market price of Atlantic Union common stock and, as such, the market value of the merger consideration at the effective time of the merger will not be known at the time American National shareholders vote on the merger. Shares of Atlantic Union common stock are listed on the New York Stock Exchange under the symbol “AUB” and shares of American National common stock are listed on The Nasdaq Global Select Market under the symbol “AMNB.” The following table sets forth the closing sale prices per share of Atlantic Union common stock and American National common stock on July 24, 2023, the last trading day before the public announcement of the signing of the merger agreement, and on September 28, 2023, the latest practicable trading day before the printing date of this proxy statement/prospectus. The table also shows the implied value of the merger consideration payable for each share of American National common stock on July 24, 2023 and on September 28, 2023, determined by multiplying the closing price of the Atlantic Union common stock on such dates by the exchange ratio. We urge you to obtain current market quotations for Atlantic Union common stock and American National common stock.

	Atlantic Union Common Stock			American National Common Stock			Implied Value of Merger Consideration
July 24, 2023		$	30.94		$	31.60		$	41.77
September 28, 2023		$	29.03		$	38.13		$	39.19

Based on the number of shares of American National common stock outstanding, including shares granted in respect of American National restricted stock awards, as of September 26, 2023, Atlantic Union expects to issue approximately 14.3 million shares of Atlantic Union common stock in the merger. However, an increase or decrease in the number of outstanding shares of American National common stock before completion of the merger could cause the actual number of shares issued in connection with the merger to change.

American National will hold a special meeting of its shareholders in connection with the merger, which we refer to as the special meeting. Atlantic Union and American National cannot complete the mergers unless the American National shareholders approve the merger agreement and the transactions contemplated thereby, which we refer to as the merger proposal. The American National board of directors is providing this proxy statement/prospectus to solicit your proxy to vote on the merger proposal and related matters. In addition, this proxy statement/prospectus is also being delivered to American National shareholders as Atlantic Union’s prospectus for its offering of Atlantic Union common stock in connection with the merger.

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The special meeting will be held on November 14, 2023 at 10:00 a.m., Eastern Time, at The Wednesday Club, 1002 Main Street, Danville, Virginia 24541.

Your vote is very important. To ensure your representation at the special meeting, please complete, sign, date and return the enclosed proxy card or submit your proxy by telephone or the internet by following the instructions on your proxy card. Whether or not you expect to attend the special meeting, please vote promptly. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

The American National board of directors has unanimously adopted the merger agreement and approved the transactions contemplated thereby and unanimously recommends to its shareholders to vote “FOR” approval of the merger proposal. The members of the American National board of directors have, as shareholders of American National, agreed to vote their shares of American National common stock to approve the merger proposal.

The accompanying proxy statement/prospectus provides a detailed description of the mergers, the merger agreement and related matters. We urge you to read the proxy statement/prospectus, including any documents incorporated in the proxy statement/prospectus by reference, and its annexes, carefully and in their entirety, including the “Risk Factors,” beginning on page 18, for a discussion of the risks relating to the mergers. You also can obtain information about Atlantic Union and American National from documents that each has filed with the Securities and Exchange Commission.

Sincerely,

Jeffrey V. Haley
President and Chief Executive Officer
American National Bankshares Inc.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities to be issued in the merger or passed upon the adequacy or accuracy of this proxy statement/prospectus. Any representation to the contrary is a criminal offense.

The securities to be issued in the merger are not savings or deposit accounts or other obligations of any bank or non-bank subsidiary of either Atlantic Union or American National, and they are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

The date of this proxy statement/prospectus is September 29, 2023, and it is first being mailed or otherwise delivered to American National shareholders on or about October 5, 2023.

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628 Main Street
Danville, Virginia 24541

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS TO BE HELD ON NOVEMBER 14, 2023

To the Shareholders of American National Bankshares Inc.:

Notice is hereby given that American National Bankshares Inc., which we refer to as American National, will hold a special meeting of shareholders, which we refer to as the special meeting, on November 14, 2023 at 10:00 a.m., Eastern Time, at The Wednesday Club, 1002 Main Street, Danville, Virginia 24541. The special meeting will be held for the purposes of allowing American National shareholders to consider and vote on the following matters:

•

a proposal to approve the Agreement and Plan of Merger, dated as of July 24, 2023, as it may be amended from time to time, which we refer to as the merger agreement, by and between Atlantic Union Bankshares Corporation, which we refer to as Atlantic Union, and American National, under which American National will merge with and into Atlantic Union, with Atlantic Union continuing as the surviving corporation, which transaction we refer to as the merger, and which proposal we refer to as the merger proposal;

•

a proposal to approve, on an advisory (non-binding) basis, specified compensation that may be paid or become payable to the named executive officers of American National that is based on or otherwise relates to the merger, which we refer to as the compensation proposal; and

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a proposal to approve one or more adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies in favor of approval of the merger proposal, which we refer to as the adjournment proposal.

These proposals are described in greater detail in the accompanying proxy statement/prospectus. American National will transact no other business at the special meeting, except for the business properly brought before the special meeting or any adjournment or postponement thereof.

American National has fixed the close of business on September 26, 2023 as the record date for the special meeting, which we refer to as the record date. Only American National shareholders of record at the close of business on the record date are entitled to notice of, and to vote at, the special meeting, or any adjournment or postponement thereof. Approval of the merger proposal requires the affirmative vote of holders of more than two-thirds of the outstanding shares of American National common stock entitled to vote on the merger proposal. Approval of the compensation proposal and the adjournment proposal each requires the affirmative vote of holders of a majority of the votes cast, in person or by proxy, at the special meeting. At the close of business on the record date, 10,629,111 shares of American National common stock were outstanding, of which 10,464,449 shares were entitled to notice of, and to vote at, the special meeting.

Your vote is very important. Atlantic Union and American National cannot complete the merger unless American National’s shareholders approve the merger proposal.

To ensure your representation at the special meeting, please complete, sign, date and return the enclosed proxy card or submit your proxy by telephone or the internet by following the instructions on your proxy card. If your shares of American National common stock are held in “street name” by a bank, broker or other nominee, please follow the instructions on the voting instruction form provided by the record holder. Whether or not you expect to attend the special meeting, please vote promptly. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

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ADDITIONAL INFORMATION

Atlantic Union and American National file reports, proxy statements and other information with the United States Securities and Exchange Commission, or the SEC, under the Securities Exchange Act of 1934, as amended, which we refer to as the Exchange Act. In addition, this proxy statement/prospectus incorporates by reference important business and financial information about Atlantic Union and American National from documents that have been filed with the SEC that are not included in or delivered with this proxy statement/prospectus. You will also be able to obtain these documents, free of charge, from Atlantic Union at www.atlanticunionbank.com or from American National at www.amnb.com. These documents are also available without charge on the SEC’s website at www.sec.gov and upon written or oral request to the applicable company’s principal executive offices. The respective addresses and telephone numbers of such principal executive offices are listed below:

	Atlantic Union Bankshares Corporation			American National Bankshares Inc.
	4300 Cox Road Richmond, Virginia 23060 Attention: Rachael R. Lape Executive Vice President, General Counsel and Corporate Secretary Telephone: (804) 633-5031			628 Main Street Danville, Virginia 24541 Attention: Jeffrey W. Farrar Senior Executive Vice President, Chief Operating and Chief Financial Officer Telephone: (434) 792-5111

The websites listed above are inactive textual references only. Except as specifically incorporated by reference into this proxy statement/prospectus, information provided on those websites is not a part of the accompanying proxy statement/prospectus and therefore is not incorporated by reference into the accompanying proxy statement/prospectus.

You will not be charged for any of these documents that you request. To receive timely delivery of these documents in advance of the special meeting, you must make your request no later than November 7, 2023 in order to receive them before the special meeting.

For a more detailed description of the information incorporated by reference into the accompanying proxy statement/prospectus and how you may obtain it, see the section entitled “Where You Can Find More Information.”

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction to or from any person to whom or from whom it is unlawful to make any such offer or solicitation in that jurisdiction. Atlantic Union and American National have not authorized anyone to provide you with information that is different from what is contained in this proxy statement/prospectus. This proxy statement/prospectus is dated September 29, 2023. You should assume that the information contained in this proxy statement/prospectus is accurate only as of such date. You should assume that the information incorporated by reference into this proxy statement/prospectus is accurate as of the date of such document. Neither the mailing of this proxy statement/prospectus to American National shareholders nor the issuance by Atlantic Union of shares of Atlantic Union common stock in connection with the merger will create any implication to the contrary.

Except where the context otherwise indicates, information contained in this proxy statement/prospectus regarding Atlantic Union has been provided by Atlantic Union and information contained in this proxy statement/prospectus regarding American National has been provided by American National.

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QUESTIONS AND ANSWERS ABOUT THE PROPOSED MERGERS AND THE SPECIAL MEETING

The following are answers to some questions that you may have regarding the mergers or the special meeting. We urge you to read carefully the remainder of this proxy statement/prospectus because the information in this section does not provide all of the information that might be important to you with respect to the mergers and the special meeting. Additional important information is also contained in the documents incorporated by reference into this proxy statement/prospectus. See the section entitled “Where You Can Find More Information.”

Unless the context otherwise requires, references in this proxy statement/prospectus to “Atlantic Union” refer to Atlantic Union Bankshares Corporation, references to “American National” refer to American National Bankshares Inc., and references to “we,” “our” and “us” refer to Atlantic Union and American National together. References in this proxy statement/prospectus to “Atlantic Union common stock” refer to the common stock of Atlantic Union, par value $1.33 per share, and references to “American National common stock” refer to the common stock of American National, par value $1.00 per share.

What are the mergers?

Atlantic Union and American National have entered into an Agreement and Plan of Merger, dated as of July 24, 2023, as it may be amended from time to time, which we refer to as the merger agreement. Under the merger agreement, American National will merge with and into Atlantic Union, with Atlantic Union continuing as the surviving corporation, which we refer to as the merger. Immediately following the merger, American National Bank and Trust Company will merge with and into Atlantic Union Bank, with Atlantic Union Bank continuing as the surviving bank, which we refer to as the bank merger and, together with the merger, as the mergers. A copy of the merger agreement is attached as Annex A to this proxy statement/prospectus. Following the merger, the shares of American National common stock will be delisted from The Nasdaq Global Select Market, or Nasdaq, and thereafter will be deregistered under the Exchange Act. The Atlantic Union common stock issued in the merger will be listed on New York Stock Exchange, or the NYSE.

Why am I receiving this proxy statement/prospectus?

American National is sending these materials to their shareholders to help them decide how to vote their shares of American National common stock with respect to the matters to be considered at the special meeting.

Atlantic Union and American National cannot complete the mergers unless the American National shareholders approve the merger agreement and the transactions contemplated thereby, including the merger. American National is holding a special meeting of its shareholders to vote on the proposals necessary to complete the mergers as well as other related matters. Information about the special meeting, the mergers and the other business to be considered by American National shareholders at the special meeting is contained in this proxy statement/prospectus.

This document constitutes both a proxy statement of American National and a prospectus of Atlantic Union. It is a proxy statement because the American National board of directors is using this document to solicit proxies from its shareholders. This document is also a prospectus because Atlantic Union, in connection with the merger, is offering shares of Atlantic Union common stock in exchange for outstanding shares of American National common stock.

What will American National shareholders receive in the merger?

If the merger is completed, each share of American National common stock, except for certain shares of American National common stock owned by American National or Atlantic Union, that is issued and outstanding immediately prior to the effective time of the merger, which we refer to as the effective time, will be converted into the right to receive 1.35 shares, which we refer to as the exchange ratio, of Atlantic Union common stock, such shares referred to as the merger consideration.

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the nearest cent) in an amount determined by multiplying (i) the average of the closing-sale prices of Atlantic Union common stock on the NYSE as reported by The Wall Street Journal for the consecutive period of ten full trading days ending on the day preceding the closing date of the merger, which we refer to as the average closing price, by (ii) the fraction of a share (rounded to the nearest one-thousandth when expressed in decimal form) of Atlantic Union common stock which such American National shareholder would otherwise be entitled to receive.

It is currently expected that the former shareholders of American National as a group will receive shares in the merger constituting approximately 16% of the outstanding shares of the combined company’s common stock immediately after the merger is completed.

Will the value of the per share merger consideration change between the date of this proxy statement/prospectus and the effective time?

Yes. Although the exchange ratio is fixed, the market value of the merger consideration will fluctuate with the market price of the Atlantic Union common stock between the date of this proxy statement/prospectus and the completion of the merger. Any change in the market price of Atlantic Union common stock after the date of this proxy statement/prospectus will change the value of the shares of Atlantic Union common stock that American National shareholders will receive.

What will happen to American National restricted stock awards in the merger?

Under the merger agreement, at the effective time, each outstanding American National restricted stock award that is unvested will fully vest and be converted automatically into the right to receive the merger consideration in respect of each share of American National common stock underlying such award.

Will the merger affect shares of Atlantic Union common stock held by current Atlantic Union shareholders?

No. Atlantic Union shareholders will continue to own their existing shares of Atlantic Union common stock after the merger is completed.

When do you expect to complete the mergers?

We expect to complete the mergers in the first quarter of 2024. However, we cannot assure you of when or if the mergers will be completed. We must first obtain the approval of American National shareholders, as well as obtain necessary regulatory approvals and satisfy certain other closing conditions. For further information, please see the section entitled “The Merger Agreement — Conditions to Completion of the Merger.”

What am I being asked to vote on?

American National shareholders are being asked to vote on the following:

•

a proposal to approve the merger agreement, a copy of which is attached as Annex A, and the transactions contemplated thereby, including the merger, which we refer to as the merger proposal;

•

Approval of the merger proposal is required to complete the mergers. American National will transact no other business at the special meeting, except for the business properly brought before the special meeting or any adjournment or postponement thereof.

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How does the American National board of directors recommend that American National shareholders vote at the special meeting?

When and where is the special meeting?

The special meeting will be held on November 14, 2023, at 10:00 a.m., Eastern Time, at The Wednesday Club, 1002 Main Street, Danville, Virginia 24541. Subject to space availability, all American National shareholders as of the record date for the special meeting, which we refer to as the record date, or their duly appointed proxies, may attend the special meeting. Since seating is limited, admission to the special meeting will be on a first come, first served basis. Registration and seating will begin at 9:30 a.m., Eastern Time.

What constitutes a quorum for the special meeting?

The presence, in person or by proxy, of holders of a majority of the shares of American National common stock outstanding and entitled to vote as of the record date will constitute a quorum for purposes of the special meeting. All shares of American National common stock entitled to vote and present in person or represented by proxy, including abstentions, if any, will be treated as present for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

Who is entitled to vote at the special meeting?

Holders of record of American National common stock at the close of business on September 26, 2023, which is the date that the American National board of directors has fixed as the record date, will be entitled to vote at the special meeting.

Ambro and Company, the nominee name that American National Bank and Trust Company uses to register the securities it holds in a fiduciary capacity for customers, held 164,662 shares of American National common stock as sole fiduciary and with sole investment authority (with no qualifying co-fiduciary having been appointed) as of the record date, which constituted 1.55% of the issued and outstanding shares of American National common stock on that date. Such shares cannot be voted at the American National special meeting and are not deemed to be outstanding and entitled to vote for purposes of determining a quorum.

What is the vote required to approve each proposal at the special meeting?

Merger proposal:

•

Standard: Approval of the merger proposal requires the affirmative vote of holders of more than two-thirds of the outstanding shares of American National common stock entitled to vote on the merger proposal.

•

Effect of abstentions and broker non-votes: If you mark “ABSTAIN” on your proxy card, fail to either submit a proxy card or vote by telephone or the internet or in person at the special meeting, or are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have the same effect as a vote “AGAINST” the merger proposal.

Compensation proposal and adjournment proposal:

•

Standard: Approval of the compensation proposal and the adjournment proposal each requires the affirmative vote of holders of a majority of the votes cast, in person or by proxy, at the special meeting.

•

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are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have no effect on the compensation proposal or the adjournment proposal.

Are there any voting agreements with existing American National shareholders?

Yes. In connection with entering into the merger agreement, the members of the American National board of directors and certain executive officers of American National, in their capacities as American National shareholders, entered into affiliate agreements, which we refer to as the affiliate agreements, in which they agreed to vote their shares of American National common stock in favor of the merger proposal and certain related matters and against alternative transactions. As of the record date, shares constituting 3.20% of American National common stock entitled to vote at the special meeting are subject to affiliate agreements. For further information, please see the section entitled “The Merger Agreement — Affiliate Agreements.”

Why is my vote important?

If you do not vote, it will be more difficult for American National to obtain the necessary quorum to hold the special meeting and to obtain the shareholder approval for the merger proposal necessary to complete the merger by the voting requirements described above. The American National board of directors unanimously recommends that American National shareholders vote “FOR” the merger proposal, “FOR” the compensation proposal, and “FOR” the adjournment proposal.

How many votes do I have?

Each holder of shares of American National common stock outstanding on the record date will be entitled to one vote for each share held of record. As of the close of business on the record date, there were 10,464,449 shares of American National common stock entitled to vote at the special meeting. As of the close of business on the record date, the directors and executive officers of American National and their affiliates beneficially owned and were entitled to vote approximately 419,414 shares of American National common stock, representing approximately 3.95% of the shares of American National common stock outstanding on that date.

What do I need to do now?

After carefully reading and considering the information contained in this proxy statement/prospectus, including any documents incorporated in this proxy statement/prospectus by reference, and its annexes, please complete, sign, date and return the enclosed proxy card and return it in the enclosed envelope or vote by telephone or the internet by following the instructions on your proxy card as soon as possible so that your shares will be represented at the special meeting.

Please follow the instructions set forth on the proxy card or on the voting instruction form provided by the record holder if your shares are held in “street name” by a bank, broker or other nominee.

How do I vote?

If you are a shareholder of record of American National as of the record date, you may submit your proxy before the special meeting in one of the following ways:

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completing, signing and dating the enclosed proxy card and returning it in the postage-paid envelope provided;

•

accessing the website specified on your proxy card and following the instructions, using the control number provided on your proxy card; or

•

calling the toll-free number specified on your proxy card and following the instructions, using the control number provided on your proxy card.

You may also cast your vote in person at the special meeting.

If your shares are held in “street name” by a bank, broker or other nominee, that institution will send you separate instructions describing the procedure for voting your shares. “Street name” shareholders who wish to vote at the special meeting will need to obtain a proxy form from their bank, broker or other nominee.

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If my shares of American National common stock are held in “street name” by my bank, broker or other nominee, will my bank, broker or other nominee automatically vote my shares for me?

No. If your shares are held in “street name” by a bank, broker or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your bank, broker or other nominee. Please note that you may not vote shares held in “street name” by returning a proxy card directly to American National or by voting in person at the special meeting unless you provide a “legal proxy,” which you must obtain from your bank, broker or other nominee.

Under stock exchange rules, banks, brokers and other nominees who hold shares of American National common stock in “street name” for a beneficial owner of those shares typically have the authority to vote in their discretion on “routine” proposals when they have not received instructions from beneficial owners. However, banks, brokers and other nominees are not allowed to exercise voting discretion with respect to the approval of matters determined to be “non-routine,” without specific instructions from the beneficial owner. Because none of the proposals to be voted on at the special meeting are “routine” matters for which banks, brokers or other nominees have discretionary authority to vote, American National does not expect any broker non-votes at the special meeting. As a result, if you do not instruct your bank, broker or other nominee on how to vote your shares, your shares will not be represented or voted on any matter at the special meeting. It is therefore critical that you cast your vote by instructing your bank, broker or other nominee on how to vote.

What will happen if I return my proxy without indicating how to vote?

If you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal, the American National common stock represented by your proxy will be voted as recommended by the American National board of directors with respect to each proposal.

May I change or revoke my vote after I have delivered my proxy?

Yes. You may change or revoke your vote at any time before your proxy is voted at the special meeting. You may do this in one of four ways:

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by completing, signing, dating and returning a proxy card with a later date than your original proxy card;

•

voting by telephone or the internet at a later time than your original vote (but before the internet and telephone voting deadline);

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by delivering a written revocation letter to American National’s corporate secretary; or

•

by attending the special meeting in person, notifying the corporate secretary and voting by ballot (your attendance alone at the applicable special meeting will not change or revoke your vote).

If your shares are held in “street name” by a bank, broker or other nominee, you should follow the instructions of your broker, bank or other nominee regarding the change or revocation of voting instructions.

Do I need identification to attend the special meeting in person?

Yes. Please bring valid photo identification, together with proof that you are a record owner of American National common stock. If you are not an American National shareholder of record or if your shares are held in “street name” by a bank, broker or other nominee, please bring a letter from the record holder of your shares confirming your beneficial ownership and a valid photo identification in order to be admitted to the meeting. A copy or printout of a brokerage statement will not be sufficient without a signed letter from the bank, broker or other nominee through which you beneficially own American National common stock. American National reserves the right to refuse admittance to anyone without proper proof of share ownership and without valid photo identification.

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Are American National shareholders entitled to dissenters’ rights?

No. Under Virginia law, American National shareholders will not be entitled to exercise any appraisal or dissenters’ rights in connection with the merger. See the section entitled “The Merger — Appraisal and Dissenters’ Rights.”

What are the material U.S. federal income tax consequences of the merger to American National shareholders?

Atlantic Union and American National intend that the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Internal Revenue Code of 1986, or the Code. In connection with the filing of the registration statement of which this proxy statement/prospectus is a part, Covington & Burling LLP, or Covington, Atlantic Union’s counsel, has delivered to Atlantic Union, and Williams Mullen, American National’s counsel, has delivered to American National, their respective opinions that, for United States federal income tax purposes, subject to the limitations, assumptions and qualifications described in “Material United States Federal Income Tax Consequences of the Merger,” the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Code. Additionally, as a condition to the respective obligations of Atlantic Union and American National to each complete the merger, Atlantic Union will receive a legal opinion from Covington and American National will receive a legal opinion from Williams Mullen, each dated as of the date the effective time occurs, which we refer to as the closing date, and each to the effect that the merger qualify as a “reorganization” within the meaning of Section 368(a) of the Code.

Accordingly, if you are a U.S. holder (as defined in the section entitled “Material United States Federal Income Tax Consequences of the Merger”) of American National common stock, you will not recognize any gain or loss for U.S. federal income tax purposes upon your exchange of shares of American National common stock for shares of Atlantic Union common stock in the merger, except with respect to cash received in lieu of fractional shares of Atlantic Union common stock. Notwithstanding the foregoing, your tax treatment will depend on your specific situation and many variables not within Atlantic Union’s or American National’s control.

The delivery of the legal opinions described above are conditions to the respective obligations of Atlantic Union and American National to each complete the merger. Neither Atlantic Union nor American National currently intends to waive these conditions to the completion of the merger. In the event that Atlantic Union or American National waives the condition to receive such tax opinion and the tax consequences of the merger materially change, then American National will recirculate appropriate soliciting materials and seek new approval of the merger from American National shareholders.

For further information, see the section entitled “Material U.S. Federal Income Tax Consequences Relating to the Merger.”

The U.S. federal income tax consequences described above may not apply to all holders of American National common stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your independent tax advisor for a full understanding of the particular tax consequences of the merger to you.

If I am an American National shareholder, should I send in my stock certificates now?

No. American National shareholders SHOULD NOT send in any stock certificates now. If the merger is completed, transmittal materials with instructions for their completion will be provided to American National shareholders after the effective time and under separate cover and the stock certificates should be sent at that time.

What should I do if I hold my shares of American National common stock in book-entry form?

If the merger is completed, you will receive written instructions from the exchange agent on how to exchange your shares of American National common stock for shares of Atlantic Union common stock that will be issued in book-entry form.

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Whom may I contact if I cannot locate my American National stock certificate(s)?

If you are unable to locate your original American National stock certificate(s), you should contact American National’s transfer agent, Computershare, at (800) 368-5948.

What should I do if I receive more than one set of voting materials?

American National shareholders may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold shares of American National common stock in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold such shares. If you are a holder of record of American National common stock and your shares are registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction card that you receive or otherwise follow the voting instructions set forth in this proxy statement/prospectus to ensure that you vote every share of American National common stock that you own.

What happens if I sell my shares of American National common stock after the record date but before the special meeting?

The record date is earlier than the date of the special meeting and the date that the merger is expected to be completed. If you transfer your shares of American National common stock after the record date but before the date of the special meeting, you will retain your right to vote at the meeting (provided that such shares remain outstanding on the date of the meeting), but you will not have the right to receive any merger consideration for the transferred shares of American National common stock. You will only be entitled to receive the merger consideration in respect of shares of American National common stock that you hold at the effective time.

Are there risks involved in undertaking the merger?

Yes. You should read and carefully consider the risk factors set forth in the section entitled “Risk Factors” beginning on page 18.

What happens if the merger is not completed?

If the merger is not completed, American National shareholders will not receive the merger consideration. Instead, each of American National and Atlantic Union will remain an independent public company and shares of common stock of each will continue to be listed on Nasdaq and the NYSE, respectively.

Whom should I contact if I have questions?

If you have any questions about the proxy materials or if you need assistance submitting your proxy or voting your shares, or need additional copies of this proxy statement/prospectus or the enclosed proxy card, you should contact American National’s corporate secretary at American National Bankshares Inc., 628 Main Street, Danville, Virginia 24541, Attention: Corporate Secretary, or American National’s proxy solicitor, Regan & Associates, Inc., at (800) 737-3426.

Where can I find more information about Atlantic Union and American National?

You can find more information about Atlantic Union and American National from the various sources described under the section entitled “Where You Can Find More Information.”

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SUMMARY

The following summary highlights selected information in this proxy statement/prospectus and may not contain all the information that may be important to you. You should read carefully this entire proxy statement/prospectus, including any document incorporated by reference in this proxy statement/prospectus, and its annexes, because this section may not contain all of the information that may be important to you in determining how to vote. For a description of, and instructions as to how to obtain, this information, see the section entitled “Where You Can Find More Information.” Each item in this summary refers to the page of this proxy statement/prospectus on which that subject is discussed in more detail.

The Companies (page 30)

Atlantic Union Bankshares Corporation
4300 Cox Road
Richmond, Virginia 23060
Telephone: (804) 633-5031

Headquartered in Richmond, Virginia, Atlantic Union Bankshares Corporation is the holding company for Atlantic Union Bank. Atlantic Union Bank has branches and ATMs located throughout Virginia and in portions of Maryland and North Carolina. Certain non-bank financial services affiliates of Atlantic Union Bank include: Atlantic Union Equipment Finance, Inc., which provides equipment financing; Atlantic Union Financial Consultants, LLC, which provides brokerage services; and Union Insurance Group, LLC, which offers various lines of insurance products. Shares of Atlantic Union’s common stock are listed on the NYSE under the symbol “AUB.”

American National Bankshares Inc.
628 Main Street
Danville, Virginia 24541
Telephone: (434) 792-5111

Headquartered in Danville, Virginia, American National Bankshares Inc. is a one-bank holding company organized under the laws of the Commonwealth of Virginia in 1984. On September 1, 1984, American National acquired all of the outstanding capital stock of American National Bank and Trust Company, a national banking association chartered in 1909 under the laws of the United States. American National Bank and Trust Company is a community bank serving its primary market areas of south central Virginia, the New River Valley and Roanoke, Virginia, and north central North Carolina. Shares of American National’s common stock are listed on Nasdaq under the symbol “AMNB.”

The Merger (page 31)

The terms and conditions of the merger are contained in the merger agreement, which is attached to this proxy statement/prospectus as Annex A. We urge you to read the merger agreement carefully and in its entirety, as it is the legal document governing the merger. All descriptions in this summary and elsewhere in this proxy statement/prospectus of the terms and conditions the merger are subject to, and qualified in their entirety by reference to, the merger agreement.

At the effective time, each share of American National common stock, excluding certain specified shares owned by Atlantic Union or American National, that is issued and outstanding immediately prior to the effective time, will be converted into the right to receive 1.35 shares of Atlantic Union common stock. Atlantic Union will not issue any fractional shares of Atlantic Union common stock in the merger. Instead, an American National shareholder who would otherwise be entitled to receive a fraction of a share of Atlantic Union common stock will receive, in lieu thereof, cash (without interest and rounded to the nearest cent) in an amount determined by multiplying (i) the average closing price by (ii) the fraction of a share (rounded to the nearest one-thousandth when expressed in decimal form) of Atlantic Union common stock which such American National shareholder would otherwise be entitled to receive.

Although the exchange ratio is fixed, the market value of the merger consideration will fluctuate with the market price of Atlantic Union common stock between the date of this proxy statement/prospectus and the completion of the merger. Based on the closing sale price of Atlantic common stock on July 24, 2023,

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the last trading day before the public announcement of the signing of the merger agreement, the implied value of the per share merger consideration payable to holders of American National common stock was $41.77. Based on the closing sale price of Atlantic Union common stock of $29.03 on September 28, 2023, the last practicable trading day before the printing of this proxy statement/prospectus, the implied value of the per share merger consideration was $39.19.

Treatment of American National Restricted Stock Awards (page 57)

At the effective time, each outstanding American National restricted stock award that is unvested will fully vest and be converted automatically into the right to receive the merger consideration in respect of each share of American National common stock underlying such award.

American National’s Reasons for the Merger and Recommendation of the American National Board of Directors (page 38)

The American National board of directors has unanimously adopted the merger agreement and approved the transactions contemplated thereby and unanimously recommends that American National’s shareholders vote “FOR” the merger proposal, “FOR” the compensation proposal and “FOR” the adjournment proposal. Please see the section entitled “The Merger — American National’s Reasons for the Merger and Recommendation of the American National Board of Directors” for a more detailed discussion of the factors considered by the American National board of directors in reaching its decision to approve the merger agreement and the transactions contemplated thereby.

Opinion of American National’s Financial Advisor (page 41)

In connection with the merger, American National’s financial advisor, Keefe, Bruyette & Woods, Inc., which we refer to as KBW, delivered a written opinion, dated July 24, 2023, to the American National board of directors as to the fairness, from a financial point of view and as of the date of the opinion, to the holders of American National common stock of the exchange ratio in the merger. The full text of the opinion, which describes the procedures followed, assumptions made, matters considered, and qualifications and limitations on the review undertaken by KBW in preparing the opinion, is attached as Annex C to this proxy statement/prospectus. The opinion was for the information of, and was directed to, the American National board of directors (in its capacity as such) in connection with its consideration of the financial terms of the merger. The opinion did not address the underlying business decision of American National to engage in the merger or enter into the merger agreement or constitute a recommendation to the American National board of directors in connection with the merger, and it does not constitute a recommendation to any holder of American National common stock or any shareholder of any other entity as to how to vote in connection with the merger or any other matter.

Atlantic Union’s Reasons for the Merger (page 55)

The Atlantic Union board of directors has unanimously adopted the merger agreement and approved the transactions contemplated thereby. Please see the section entitled “The Merger — Atlantic Union’s Reasons for the Merger and Recommendations of the Atlantic Union Board of Directors” for a more detailed discussion of the factors considered by the Atlantic Union board of directors in reaching its decision to adopt the merger agreement and approve the transactions contemplated thereby.

The Special Meeting (page 24)

American National will hold the special meeting at The Wednesday Club, 1002 Main Street, Danville, Virginia 24541, at 10:00 a.m., Eastern Time, on November 14, 2023. At the special meeting, American National shareholders will be asked to consider and vote on the merger proposal, the compensation proposal and the adjournment proposal, if necessary or appropriate.

American National has set the close of business on September 26, 2023 as the record date to determine which American National shareholders will be entitled to receive notice of and vote at the special meeting. Each holder of shares of American National common stock outstanding on the record date will be entitled to one vote for each share held of record. As of the close of business on the record date, there were 10,464,449

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shares of American National common stock entitled to vote at the special meeting. As of the record date, the directors and executive officers of American National and their affiliates beneficially owned and were entitled to vote approximately 419,414 shares of American National common stock, representing approximately 3.95% of the shares of American National common stock outstanding on that date.

Approval of the merger proposal requires the affirmative vote of holders of more than two-thirds of the outstanding shares of American National common stock entitled to vote on the merger proposal. Approval of the compensation proposal and the adjournment proposal each requires the affirmative vote of holders of a majority of the votes cast, in person or by proxy, at the special meeting.

With respect to the merger proposal, if you mark “ABSTAIN” on your proxy card, fail to either submit a proxy card or vote by telephone or the internet or in person at the special meeting, or are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have the same effect as a vote “AGAINST” the merger proposal. With respect to the compensation proposal and the adjournment proposal, if you mark “ABSTAIN” on your proxy card, fail to either submit a proxy card or vote by telephone or the internet or in person at the special meeting, or are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have no effect on such proposals.

Interests of American National’s Directors and Executive Officers in the Merger (page 57)

In considering the recommendation of the American National board of directors, American National shareholders should be aware that American National’s directors and executive officers have interests in the merger that may be different from, or in addition to, the interests of the American National shareholders generally. The American National board of directors was aware of these interests and considered them, among other matters, in adopting the merger agreement and approving the transactions contemplated thereby and in determining to recommend to the American National shareholders that they vote to approve the merger proposal.

These interests are described in more detail under the section entitled “The Merger — Interests of American National’s Directors and Executive Officers in the Merger.”

Governance of Atlantic Union Following the Completion of the Merger (page 57)

Regulatory Approvals Required for the Mergers (page 61)

The completion of the mergers is subject to prior receipt of certain approvals and consents required to be obtained from applicable governmental and regulatory authorities. These approvals include approvals from the Board of Governors of the Federal Reserve System, which we refer to as the Federal Reserve, and the Bureau of Financial Institutions of the Virginia State Corporation Commission, which we refer to as the VBFI. Atlantic Union and American National have filed all necessary applications and notifications to obtain the required regulatory approvals, consents and waivers. Although neither Atlantic Union nor American National knows of any reason why the parties cannot obtain regulatory approvals required to complete the mergers in a timely manner, Atlantic Union and American National cannot be certain of when or if such approvals will be obtained.

Accounting Treatment of the Merger (page 62)

The merger will be accounted for as an acquisition by Atlantic Union using the acquisition method of accounting in accordance with FASB ASC Topic 805, “Business Combinations.” Accordingly, the acquired assets (including separately identifiable intangible assets) and assumed liabilities of American National as of the date of acquisition will be recorded at their respective fair values and added to those of Atlantic Union. The excess of the total consideration paid in connection with the merger over the net fair values is recorded as goodwill.

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Public Trading Markets (page 62)

Atlantic Union common stock is listed on the NYSE under the symbol “AUB.” American National common stock is listed on Nasdaq under the symbol “AMNB.” Upon completion of the merger, American National common stock will be delisted from Nasdaq and thereafter will be deregistered under the Exchange Act. The Atlantic Union common stock issued in the merger will be listed on the NYSE.

Appraisal Rights of American National Shareholders (page 62)

Under Virginia law, American National shareholders will not be entitled to exercise any appraisal or dissenters’ rights in connection with the merger.

Agreement Not to Solicit Other Offers (page 72)

American National has agreed that it will not, and will cause its subsidiaries and its subsidiaries’ respective representatives not to, directly or indirectly:

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initiate, solicit, encourage or facilitate any inquiries or proposals with respect to any acquisition proposal (as defined in “The Merger Agreement — Agreement Not to Solicit Other Offers”);

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engage or participate in any negotiations or discussions concerning any acquisition proposal;

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provide any confidential or nonpublic information or data to, or have or participate in any discussions with, any person relating to any acquisition proposal;

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waive, amend, release or fail to enforce, any confidentiality, standstill or similar agreement; or

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unless the merger agreement has been terminated, approve or enter into any term sheet, letter of intent, commitment or other agreement (whether written or oral, binding or nonbinding) that are based on or related to any acquisition proposal.

Notwithstanding American National’s non-solicitation obligations described above, if after the date of the merger agreement and before the approval of the merger proposal, American National receives an unsolicited, bona fide written acquisition proposal that did not result from or arise in connection with a breach of its non-solicitation obligations, then American National may, and may permit its subsidiaries and its subsidiaries’ representatives to, furnish confidential or nonpublic information or data to and participate in negotiations or discussions with the person making the acquisition proposal if (i) the American National board of directors concludes in good faith (after consulting with its outside counsel, and with respect to financial matters, its financial advisors) that such acquisition proposal constitutes or could reasonably be expected to lead to, a superior proposal (as defined in “The Merger Agreement — Agreement Not to Solicit Other Offers”) and that the failure to take such actions would be reasonably likely to be a violation of its fiduciary duties under applicable law, (ii) American National provides Atlantic Union with at least one business day notice before providing such confidential or nonpublic information or data to the person making an acquisition proposal, and (iii) before furnishing any confidential or nonpublic information or data, American National provides such information to Atlantic Union and enters into a confidentiality agreement with the person making such acquisition proposal on terms no less favorable to it than the confidentiality agreement between Atlantic Union and American National, dated June 8, 2023, which confidentiality agreement will not provide such person with any exclusive right to negotiate with American National or otherwise prevent American National from providing any information to Atlantic Union in accordance with the merger agreement or otherwise comply with its obligations under the merger agreement.

Special Meeting and Recommendation of the American National Board of Directors (page 74)

American National has agreed to call a meeting of its shareholders to be held as soon as reasonably practicable after this proxy statement/prospectus is declared effective for the purpose of receiving approval of the merger proposal.

The American National board of directors has agreed to recommend to American National shareholders the approval of the merger proposal, and to include such recommendation in this proxy statement/prospectus and to solicit and use its reasonable best efforts to obtain the approval of the merger proposal. The American

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National board of directors agreed to not (i) withhold, withdraw, modify or qualify in a manner adverse to Atlantic Union, such recommendation, (ii) fail to make such recommendation in this proxy statement/prospectus, or otherwise submit the merger agreement to its shareholders for adoption and approval without such recommendation, (iii) adopt, approve, agree to, accept, recommend or endorse an acquisition proposal or publicly announce an intention to adopt, approve, recommend or endorse an acquisition proposal, (iv) fail to publicly and without qualification recommend against any acquisition proposal or reaffirm the recommendation of the American National board of directors within ten business days after an acquisition proposal is made public or any request by Atlantic Union to do so, (v) take any action, or make any public statement, filing or release inconsistent with the recommendation of the American National board of directors, or (vi) publicly propose to do any of the foregoing, each of which we refer to as a change in recommendation.

However, at any time before the receipt of the approval of the merger proposal, American National may (i) submit the merger agreement to American National shareholders without recommendation and communicate the basis for the lack of a recommendation in this proxy statement/prospectus or any amendment or supplement to this proxy statement/prospectus to the extent required by law, or (ii) terminate the merger agreement and enter into an acquisition agreement with respect to a superior proposal subject to compliance with the termination fee provisions in the merger agreement. The American National board of directors may only take such actions if:

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American National receives a superior proposal;

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the American National board of directors, after consulting with its outside counsel and, with respect to financial matters, its financial advisors, determines in good faith that it would be reasonably likely to be a violation of its fiduciary duties under applicable law to recommend the merger;

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American National has complied in all material respects with its non-solicitation obligations under the merger agreement;

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American National gives Atlantic Union at least five business days’ prior written notice of its intention to take the actions described above and gives a reasonable description of the event or circumstances giving rise to its determination to take such action, including the latest material terms and conditions and the identity of the third party making any such superior proposal; and

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the American National board of directors, at the end of such five business day period, determines in good faith that such superior proposal remains a superior proposal (taking into account any amendment or modification to the merger agreement proposed by Atlantic Union), after consulting with its outside counsel and, with respect to financial matters, its financial advisors, and it would be reasonably likely to be a violation of its fiduciary duties under applicable law to recommend the merger.

Any material amendment to any acquisition proposal will require a new determination and notice period, except that the notice period will be three business days rather than five business days.

Conditions to Completion of the Merger (page 74)

The obligation of each party to complete the merger is subject to the satisfaction or waiver at or before the effective time of the following conditions:

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the approval of the merger proposal;

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the approval of the listing on the NYSE of the Atlantic Union common stock to be issued in the merger;

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the receipt of all requisite regulatory approvals;

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the effectiveness of the registration statement of which this proxy statement/prospectus is a part under the Securities Act of 1933, as amended, or the Securities Act, and there being no stop order or proceeding by the SEC to suspend the effectiveness of the registration statement;

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no order, injunction or decree by any court or governmental entity of competent jurisdiction or other legal restraint or prohibition preventing the completion of the merger or any of the other

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transactions contemplated by the merger agreement being in effect, and no law, statute, rule, regulation, order, injunction or decree having been enacted, entered, promulgated or enforced by any governmental entity which prohibits or makes illegal the completion of the merger or any of the other transactions contemplated by the merger agreement;

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the accuracy of the representations and warranties of the other party in the merger agreement as of the date of the merger agreement and as of the closing date, subject to the materiality standards provided in the merger agreement, and the receipt by each party of a certificate signed on behalf of the other party to the foregoing effect;

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the performance by the other party in all material respects of all obligations, covenants and agreements of such party required to be performed by it under the merger agreement at or before the effective time, and the receipt by each party of a certificate signed on behalf of the other party to the foregoing effect;

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the receipt by each party of a written opinion of its counsel to the effect that the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Code; and

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in the case of Atlantic Union, the receipt of requisite regulatory approvals without the imposition of a materially burdensome regulatory condition.

We cannot be certain of when, or if, the conditions to the merger will be satisfied or waived, or that the mergers will be completed in the first quarter of 2024 or at all. As of the date of this proxy statement/prospectus, we have no reason to believe that any of these conditions will not be satisfied.

Termination of the Merger Agreement (page 75)

The merger agreement may be terminated at any time before the effective time (whether before or after the approval of the merger by American National shareholders) by mutual written consent, or by either party in the following circumstances:

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if (i) any governmental entity denies a requisite regulatory approval and such denial is final and non-appealable or has advised Atlantic Union that it will not grant (or intends to rescind or revoke) a requisite regulatory approval, (ii) any governmental entity has requested in writing that Atlantic Union, American National or any of their respective affiliates withdraw (other than for technical reasons), and not be permitted to resubmit within 60 days, any application with respect to a requisite regulatory approval, or (iii) any governmental entity has issued a final and nonappealable order, injunction, decree or other legal restraint or prohibition permanently enjoining or otherwise prohibiting or making illegal the completion of the mergers;

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if the approval of the merger proposal is not obtained at the special meeting, which we refer to as a no-vote termination;

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if the merger has not been completed by July 24, 2024, which we refer to as the outside date, if the failure to complete the transactions contemplated by the merger agreement on or before the outside date is not caused by the terminating party’s breach of the merger agreement, which we refer to as an outside date termination; or

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if there was a breach of any representation, warranty, obligation, covenant or other agreement contained in the merger agreement on the part of American National, in the case of a termination by Atlantic Union, or Atlantic Union, in the case of a termination by American National, which breach or failure to be true would, either individually or in the aggregate with all other breaches by such party, constitute the failure of a Atlantic Union or American National condition to closing, respectively, and is not cured within 45 days following written notice or by its nature cannot be cured during such period, as long as the terminating party is not then in material breach of any representation, warranty, obligation, covenant or other agreement contained in the merger agreement, which we refer to as a breach termination.

In addition, Atlantic Union may terminate the merger agreement if:

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before obtaining the approval of the merger proposal, the American National board of directors effects a change in recommendation or American National breaches its obligations with respect to

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not soliciting acquisition proposals, holding the special meeting or making its recommendation to approve the merger proposal; or

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a governmental entity grants a requisite regulatory approval but such requisite regulatory approval contains, results in or would reasonably be expected to result in, the imposition of a materially burdensome regulatory condition.

In addition, American National may terminate the merger agreement if before obtaining the approval of the merger proposal, the American National board of directors determines to enter into an acquisition agreement with respect to a superior proposal in accordance with its obligations with respect to acquisition proposals.

American National will pay Atlantic Union a $17,232,000 termination fee if:

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(i) either American National or Atlantic Union effects a no-vote termination, (ii) either American National or Atlantic Union effects an outside date termination (and the approval of the merger proposal has not been obtained), or (iii) Atlantic Union effects a breach termination and, in each case, American National enters into a definitive agreement or completes a transaction with respect to an acquisition proposal within 12 months of such termination;

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Atlantic Union terminates the merger agreement because American National board of directors has effected a change in recommendation or American National breached its obligations with respect to not soliciting acquisition proposals, holding the special meeting or making its recommendation to approve the merger proposal; or

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American National terminates the merger agreement because the American National board of directors determines to enter into an acquisition agreement with respect to a superior proposal in accordance with its obligations with respect to acquisition proposals.

Affiliate Agreements (page 77)

In connection with entering into the merger agreement, the members of the American National board of directors and certain executive officers of American National, in their capacities as American National shareholders, entered into affiliate agreements in which they agreed to vote their shares of American National common stock in favor of the merger proposal and certain related matters and against alternative transactions. As of the record date, shares constituting 3.20% of the American National common stock entitled to vote at the special meeting are subject to affiliate agreements.

Material U.S. Federal Income Tax Consequences Relating to the Merger (page 78)

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in lieu of fractional shares of Atlantic Union common stock. Notwithstanding the foregoing, your tax treatment will depend on your specific situation and many variables not within Atlantic Union’s or American National’s control.

Comparison of Shareholders’ Rights (page 90)

Upon completion of the merger, the rights of former American National shareholders will be governed by the articles of incorporation and bylaws of Atlantic Union, each as amended and restated to date, which we refer to as the Atlantic Union articles and the Atlantic Union bylaws, respectively. The rights associated with American National common stock are different from the rights associated with Atlantic Union common stock. Please see the section entitled “Comparison of Shareholders’ Rights” for a discussion of the different rights associated with Atlantic Union common stock.

Risk Factors (page 18)

Before voting at the special meeting, you should carefully consider all of the information contained in or incorporated by reference into this proxy statement/prospectus, including the risk factors set forth in the section entitled “Risk Factors” and described in each of Atlantic Union’s and American National’s Annual Report on Form 10-K for the year ended on December 31, 2022, Quarterly Reports on Form 10-Q for the quarters ended March 31, 2023 and June 30, 2023, and other reports filed by Atlantic Union and American National with the SEC, which are incorporated by reference into this proxy statement/prospectus. Please see the section entitled “Where You Can Find More Information.”

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this proxy statement/prospectus may constitute “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are not statements of historical fact and include projections, predictions, expectations, or beliefs about future events or results. Examples of forward-looking statements include, but are not limited to, statements regarding the outlook and expectations of Atlantic Union and American National with respect to the proposed mergers, the strategic benefits and financial benefits of the proposed mergers, including the expected impact of the proposed mergers on the combined company’s future financial performance (including anticipated accretion to earnings per share, the tangible book value earn-back period and other operating and return metrics), assumed purchase accounting adjustments, the timing of the closing of the proposed mergers, and the ability to successfully integrate the combined businesses. Such forward-looking statements are based on various assumptions as of the time they are made, and are inherently subject to known and unknown risks, uncertainties and other factors that may cause actual results, performance or achievements to be materially different from those expressed or implied by such forward-looking statements. Forward-looking statements are often accompanied by words that convey projected future events or outcomes such as “expect,” “believe,” “estimate,” “plan,” “project,” “anticipate,” “intend,” “will,” “may,” “view,” “opportunity,” “potential,” or words of similar meaning or other statements concerning opinions or judgment of Atlantic Union or American National or their management about future events. Although each of Atlantic Union and American National believes that its expectations with respect to forward-looking statements are based upon reasonable assumptions within the bounds of its existing knowledge of its business and operations, there can be no assurance that actual results, performance, or achievements of Atlantic Union or American National will not differ materially from any projected future results, performance, or achievements expressed or implied by such forward-looking statements.

In addition to factors previously disclosed in Atlantic Union’s and American National’s reports filed with the SEC, and those identified elsewhere in this filing (including the section entitled “Risk Factors” beginning on page 18), the following factors, among others, could cause actual results to differ materially from forward-looking statements or historical performance:

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the occurrence of any event, change or other circumstances that could give rise to the right of one or both of the parties to terminate the merger agreement;

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the failure to obtain necessary regulatory approvals (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the mergers) and the approval by American National shareholders, on a timely basis or at all;

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the possibility that the anticipated benefits of the mergers, including anticipated cost savings and strategic gains, are not realized when expected or at all;

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the possibility that the integration of the two companies may be more difficult, time-consuming or costly than expected;

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the impact of purchase accounting with respect to the mergers, or any change in the assumptions used regarding the assets acquired and liabilities assumed to determine their fair value and credit marks, particularly in light of the current rising interest rate environment;

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the outcome of any legal proceedings that may be instituted against Atlantic Union or American National;

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the possibility that the mergers may be more expensive or take longer to complete than anticipated, including as a result of unexpected factors or events;

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diversion of management’s attention from ongoing business operations and opportunities;

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potential adverse reactions or changes to business or employee relationships, including those resulting from the announcement or completion of the mergers;

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changes in Atlantic Union’s or American National’s share price before closing;

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risks relating to the dilutive effect of shares of Atlantic Union’s common stock to be issued in the merger; and

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other factors that may affect future results of Atlantic Union or American National including changes in asset quality and credit risk; the inability to sustain revenue and earnings growth; changes in interest rates; deposit flows; inflation; customer borrowing, repayment, investment and deposit practices; the impact, extent and timing of technological changes; capital management activities; and actions of the Federal Reserve and legislative and regulatory actions and reforms.

We refer you to the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of Atlantic Union’s and American National’s Annual Report on Form 10-K for the year ended December 31, 2022 and comparable sections of Atlantic Union’s and American National’s Quarterly Reports on Form 10-Q, and other filings with the SEC, which are available on the SEC’s website at www.sec.gov. All of the forward-looking statements included in this proxy statement/prospectus are expressly qualified by the cautionary statements contained or referred to herein. The actual results or developments anticipated may not be realized or, even if substantially realized, they may not have the expected consequences to or effects on Atlantic Union, American National or their respective businesses or operations. Readers are cautioned not to rely on the forward-looking statements contained in this proxy statement/prospectus. Forward-looking statements speak only as of the date they are made and neither Atlantic Union nor American National undertakes any obligation to update, revise or clarify these forward-looking statements, whether as a result of new information, future events or otherwise.

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RISK FACTORS

In addition to the other information contained in or incorporated by reference into this proxy statement/prospectus, including the matters addressed under the section entitled “Cautionary Statement Regarding Forward-Looking Statements,” and the matters discussed under the captions “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of Atlantic Union’s Annual Report on Form 10-K for the year ended December 31, 2022, American National’s Annual Report on Form 10-K for the year ended December 31, 2022 and any updates to those risk factors set forth in Atlantic Union’s and American National’s Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other filings which have been filed with the SEC, American National shareholders should carefully consider the following factors in deciding whether to vote for the proposals presented in this proxy statement/prospectus. Please also see the section entitled “Where You Can Find More Information.”

Risks Relating to the Mergers

Failure to complete the merger could negatively impact Atlantic Union and American National.

The merger agreement is subject to a number of conditions which must be fulfilled in order to complete the merger. If the merger is not completed for any reason, there may be various adverse consequences and each company may experience negative reactions from the financial markets and from its customers and employees. For example, either party’s business may have been impacted adversely by the failure to pursue other beneficial opportunities due to the focus of its management on the merger, without realizing any of the anticipated benefits of completing the merger. Additionally, if the merger agreement is terminated, the market price of each company’s common stock could decline to the extent that current market prices reflect a market assumption that the merger will be beneficial and will be completed. Atlantic Union and/or American National also could be subject to litigation related to any failure to complete the merger or to proceedings commenced against either company to perform our obligations under the merger agreement.

Additionally, Atlantic Union and American National have incurred and will incur substantial expenses relating to negotiation and completion of the transactions contemplated by the merger agreement. If the merger is not completed, each party would have to recognize these expenses without realizing the expected benefits of the merger.

Regulatory approvals may not be received, may take longer than expected or may impose conditions that are not presently anticipated, cannot be met, or that could have an adverse effect on the combined company following the merger.

Before the merger and the bank merger may be completed, various approvals, consents and non-objections must be obtained from bank regulatory authorities, including the Federal Reserve. In determining whether to grant these approvals, the regulators consider a variety of factors, including the regulatory standing of each party. These approvals could be delayed or not obtained at all, including due to an adverse development in either party’s regulatory standing or in any other factors considered by regulators in granting such approvals; governmental, political or community group inquiries, investigations or opposition; or changes in legislation or the political or regulatory environment generally.

The approvals that are granted may impose terms and conditions, limitations, obligations or costs, or place restrictions on the conduct of the combined company’s business or require changes to the terms of the transactions contemplated by the merger agreement. There can be no assurance that regulators will not impose any such conditions, limitations, obligations or restrictions and that such conditions, limitations, obligations or restrictions will not have the effect of delaying the completion of any of the transactions contemplated by the merger agreement, imposing additional material costs on or materially limiting the revenues of the combined company following the merger or otherwise reduce the anticipated benefits of the merger if the merger were completed successfully within the expected timeframe. In addition, there can be no assurance that any such conditions, terms, obligations or restrictions will not result in the delay or abandonment of the merger. The completion of the merger is conditioned on the receipt of the requisite regulatory approvals without the imposition of any materially financially burdensome regulatory condition and the expiration of all statutory waiting periods. Additionally, the completion of the merger is conditioned on the absence of certain laws, orders, injunctions or decrees issued by any court or governmental entity of

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competent jurisdiction that would prevent, prohibit or make illegal the completion of the merger, the bank merger or any of the other transactions contemplated by the merger agreement.

If the completion of the merger is delayed, including by a delay in receipt of necessary regulatory approvals, the business, financial condition and results of operations of each party may be adversely affected.

Because the exchange ratio is fixed and the market price of Atlantic Union common stock will fluctuate, the value of the merger consideration to be received by American National shareholders may change.

Under the merger agreement, upon completion of the merger, each share of American National common stock, except for certain shares of American National common stock owned by American National or Atlantic Union, that is issued and outstanding immediately prior to the effective time will be converted into the right to receive 1.35 shares of Atlantic Union common stock. The closing price of Atlantic Union common stock on the date that the merger is completed may vary from the closing price of Atlantic Union common stock on the date Atlantic Union and American National announced the signing of the merger agreement, the date that this proxy statement/prospectus is being mailed or otherwise delivered to American National shareholders and the date of the special meeting. Because the merger consideration is determined by a fixed exchange ratio, at the time of the special meeting, American National shareholders will not know or be able to calculate the value of the shares of Atlantic Union common stock they will receive upon completion of the merger. Any change in the market price of Atlantic Union common stock before completion of the merger may affect the value of the merger consideration that American National shareholders will receive upon completion of the merger. Stock price changes may result from a variety of factors, including general market and economic conditions, changes in the companies’ respective businesses, operations and prospects, changes in estimates or recommendations by securities analysts or ratings agencies, and regulatory considerations, among other things. Many of these factors are beyond the control of Atlantic Union and American National. American National shareholders should obtain current market quotations for shares of Atlantic Union common stock and American National common stock before voting their shares at the special meeting.

Shareholder litigation could prevent or delay the completion of the merger or otherwise negatively impact our business, financial condition and results of operations.

Shareholders of Atlantic Union and/or American National may file lawsuits against Atlantic Union, American National and/or the directors and officers of either company in connection with the merger. One of the conditions to the closing is that no law, order, injunction or decree issued by any court or governmental entity of competent jurisdiction that would prevent, prohibit or make illegal the completion of the merger, the bank merger or any of the other transactions contemplated by the merger agreement be in effect. If any plaintiff were successful in obtaining an injunction prohibiting Atlantic Union or American National from completing the merger, the bank merger or any of the other transactions contemplated by the merger agreement, then such injunction may delay or prevent the effectiveness of the merger and could result in significant costs to either party, including any cost associated with the indemnification of its directors and officers. Each party may incur costs relating to the defense or settlement of any shareholder lawsuits filed in connection with the merger. Shareholder lawsuits may divert management attention from management of each company’s business or operations. Such litigation could have an adverse effect on such party’s business, financial condition and results of operations and could prevent or delay the completion of the merger.

Some of the conditions to the merger may be waived by American National or Atlantic Union without resoliciting approval of the merger proposal.

Some of the conditions to the merger set forth in the merger agreement may be waived by American National or Atlantic Union, subject to the agreement of the other party in specific cases. See the section entitled “The Merger Agreement — Conditions to Completion of the Merger.” If any such conditions are waived, American National and Atlantic Union will evaluate whether an amendment of this proxy statement/prospectus and resolicitation of proxies is warranted. In the event that the American National board of

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directors determines that resolicitation of American National shareholders is not warranted, American National and Atlantic Union will have the discretion to complete the merger without seeking further approval of the merger proposal.

American National and Atlantic Union will be subject to business uncertainties and contractual restrictions while the mergers are pending.

Uncertainty about the effect of the mergers on employees, customers (including depositors and borrowers), suppliers and vendors may have an adverse effect on the business, financial condition and results of operations of American National and Atlantic Union. These uncertainties may impair American National’s and Atlantic Union’s ability to attract, retain and motivate key personnel and customers (including depositors and borrowers) pending the completion of the mergers, as such personnel and customers may experience uncertainty about their future roles and relationships following the completion of the mergers. Additionally, these uncertainties could cause customers (including depositors and borrowers), suppliers, vendors and others who deal with American National and Atlantic Union to seek to change existing business relationships with American National and Atlantic Union or fail to extend an existing relationship with American National or Atlantic Union, as applicable. In addition, competitors may target each party’s existing customers by highlighting potential uncertainties and integration difficulties that may result from the mergers.

The pursuit of the merger and the preparation for the integration may place a burden on American National’s and Atlantic Union’s management and internal resources. Any significant diversion of management attention away from ongoing business concerns and any difficulties encountered in the transition and integration process could have an adverse effect on American National’s or Atlantic Union’s business, financial condition and results of operations.

In addition, the merger agreement restricts American National from taking certain actions without Atlantic Union’s consent while the merger is pending. These restrictions could prevent American National from pursuing attractive business opportunities that may arise prior to completion of the merger. Please see the section entitled “The Merger Agreement — Covenants and Agreements — Conduct of Business Prior to the Effective Time” for a description of the restrictive covenants applicable to American National.

American National’s directors and executive officers may have interests in the mergers different from the interests of other American National shareholders.

American National’s directors and executive officers have interests in the mergers that may be different from, or in addition to, the interests of the American National shareholders generally. The American National board of directors was aware of these interests and considered them, among other matters, in adopting the merger agreement and approving the transactions contemplated by the merger agreement and in determining to recommend to the American National shareholders that they vote to approve the merger proposal. These interests are described in more detail under the section entitled “The Merger — Interests of American National’s Directors and Executive Officers in the Merger.”

Shares of Atlantic Union common stock to be received by American National shareholders as a result of the merger will have rights different from the shares of American National common stock.

The rights of American National shareholders are currently governed by the articles of incorporation and the bylaws of American National, each as amended and restated to date, which we refer to as the American National articles and the American National bylaws, respectively. Upon completion of the merger, the rights of former American National shareholders will be governed by the Atlantic Union articles and the Atlantic Union bylaws. The rights associated with American National common stock are different from the rights associated with Atlantic Union common stock. Please see the section entitled “Comparison of Shareholders’ Rights” for a discussion of the different rights associated with Atlantic Union common stock.

The merger agreement contains provisions that may discourage other companies from pursuing, announcing or submitting a business combination proposal to American National that might result in greater value to American National shareholders.

The merger agreement contains provisions that may discourage a third party from pursuing, announcing or submitting a business combination proposal to American National that might result in greater value to

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the American National shareholders than the merger. These provisions include a general prohibition on American National from soliciting, or, subject to certain exceptions, entering into discussions with any third party regarding any acquisition proposal or offers for competing transactions, as described under the section entitled “The Merger Agreement — Agreement Not to Solicit Other Offers.” Furthermore, if the merger agreement is terminated, under certain circumstances, American National may be required to pay Atlantic Union a termination fee equal to $17,232,000, as described under the section entitled “The Merger Agreement — Termination Fee.” American National also has an obligation to submit the merger proposal to a vote of its shareholders, even if American National receives an unsolicited acquisition proposal that the American National board of directors believes is superior to the merger, unless the merger agreement is terminated by American National under certain conditions as described under the section entitled “The Merger Agreement — Termination of the Merger Agreement.” See also the section entitled “The Merger Agreement — Special Meeting and Recommendation of the American National Board of Directors.”

Each of the members of the American National board of directors and certain executive officers of American National, in their capacities as shareholders of American National, entered into affiliate agreements in which they agreed to vote their shares of American National common stock in favor of the merger proposal and certain related matters and against alternative transactions. As of the record date, shares constituting 3.20% of American National common stock entitled to vote at the special meeting were held by signatories to affiliate agreements. For further information, please see the section entitled “The Merger Agreement — Affiliate Agreements.”

The opinion of KBW delivered to the American National board of directors before the signing of the merger agreement will not reflect changes in circumstances that occur after the date of the opinion.

Before the execution of the merger agreement, the American National board of directors received an opinion from KBW, American National’s financial advisor, as to the fairness, from a financial point of view, to American National shareholders of the exchange ratio in the merger, which opinion was delivered on and dated July 24, 2023. Subsequent changes in the operations and prospects of American National or Atlantic Union, general market and economic conditions and other factors that may be beyond the control of American National and Atlantic Union may significantly alter the value of American National or Atlantic Union or the price of the shares of American National common stock or Atlantic Union common stock by the time the merger is completed. The opinion does not speak as of the effective time or as of any other date other than the date of such opinion. For a description of the opinion received by the American National board of directors, please refer to the section entitled, “The Merger — Opinion of American National’s Financial Advisor.”

Risks Relating to the Combined Company’s Business Following the Mergers

The market price of the common stock of the combined company after the merger may be affected by factors different from those currently affecting the shares of Atlantic Union or American National common stock.

Upon the completion of the merger, Atlantic Union shareholders and American National shareholders will be shareholders of the combined company. Atlantic Union’s business differs from that of American National, and, accordingly, the results of operations of the combined company and the market price of the combined company’s shares of common stock may be affected by factors different from those currently affecting the independent results of operations of each of Atlantic Union and American National. For a discussion of the businesses of Atlantic Union and American National, please see the section entitled “Information About the Companies.” For a discussion of the businesses of Atlantic Union and American National and of certain factors to consider in connection with such businesses, please see the documents incorporated by reference in this proxy statement/prospectus and referred to in the section entitled “Where You Can Find More Information.”

Combining Atlantic Union and American National may be more difficult, costly or time consuming than expected and the combined company may fail to realize the anticipated benefits and cost savings of the merger.

The success of the merger will depend, in part, on the ability to realize the anticipated cost savings from combining the businesses of Atlantic Union and American National. To realize the anticipated

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benefits and cost savings from the merger, Atlantic Union and American National must successfully integrate and combine their businesses in a manner that permits those cost savings to be realized. If Atlantic Union and American National are not able to successfully achieve these objectives, the anticipated benefits of the merger may not be realized fully or at all or may take longer to realize than expected. In addition, the actual cost savings and anticipated benefits of the merger could be less than anticipated, and integration may result in additional unforeseen expenses.

An inability to realize the full extent of the anticipated benefits of the merger and the other transactions contemplated by the merger agreement, as well as any delays encountered in the integration process, could have an adverse effect on the revenues, levels of expenses and operating results of the combined company following the completion of the merger, which may adversely affect the value of the common stock of the combined company following the completion of the merger.

Atlantic Union and American National have operated and, until the completion of the merger, must continue to operate, independently. It is possible that the integration process could result in the loss of key employees, the disruption of each company’s ongoing business or inconsistencies in standards, controls, procedures and policies that adversely affect each company’s ability to maintain relationships with clients, customers, depositors and employees or to achieve the anticipated benefits and cost savings of the merger. Integration efforts may also divert management attention during this transition period and for an undetermined period after completion of the merger, which may have an adverse effect on the combined company.

The combined company expects to incur substantial expenses related to the mergers.

The combined company expects to incur substantial expenses in connection with completion of the mergers and combining the business, operations, networks, systems, technologies, policies and procedures of the two companies. Although Atlantic Union and American National have assumed that a certain level of transaction and combination expenses would be incurred, there are a number of factors beyond their control that could affect the total amount or the timing of their combination expenses. Many of the expenses that will be incurred are, by their nature, difficult to estimate accurately at the present time. As a result of these expenses, both Atlantic Union and American National expect to take charges against their earnings before, and Atlantic Union expects to take charges against its earnings after, the completion of the mergers. The charges taken in connection with the mergers are expected to be significant, although the aggregate amount and timing of such charges are uncertain at present. There can be no assurance that the anticipated benefits and cost savings related to the integration of the businesses will be realized to offset these transaction and integration expenses over time.

Atlantic Union and American National shareholders will have a reduced ownership and voting interest after the merger and will exercise less influence over management.

Atlantic Union shareholders currently have the right to vote in the election of the Atlantic Union board of directors and on other matters affecting Atlantic Union. American National shareholders currently have the right to vote in the election of the American National board of directors and on other matters affecting American National. Upon the completion of the merger, each shareholder of either party will be a shareholder of Atlantic Union with a percentage ownership of Atlantic Union that is smaller than such shareholder’s current percentage ownership of Atlantic Union or American National, as applicable. It is currently expected that the former American National shareholders as a group will receive shares in the merger constituting approximately 16% of the outstanding shares of the combined company’s common stock immediately after the completion of the merger. Current Atlantic Union shareholders as a group are expected to own approximately 84% of the outstanding shares of the combined company immediately after the completion of the merger. As a result, Atlantic Union and American National shareholders will have less influence on the management and policies of the combined company than they now have on the management and policies of Atlantic Union or American National, as applicable.

Issuance of shares of Atlantic Union common stock in connection with the merger may adversely affect the market price of Atlantic Union common stock.

In connection with the payment of the merger consideration, Atlantic Union expects to issue approximately 14.4 million shares of Atlantic Union common stock to American National shareholders.

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The issuance of these new shares of Atlantic Union common stock may result in fluctuations in the market price of Atlantic Union common stock, including a stock price decrease.

The unaudited pro forma condensed combined financial information included in this proxy statement/prospectus is illustrative only and the actual financial condition and results of operations after the merger may differ materially.

The unaudited pro forma condensed combined financial statements in this proxy statement/prospectus are presented for illustrative purposes only. The unaudited pro forma condensed combined financial statements are not necessarily, and should not be assumed to be, an indication of the results that would have been achieved had the merger been completed as of the dates indicated or that may be achieved in the future. A final determination of the fair values of American National’s assets and liabilities, which cannot be made prior to the completion of the merger, will be based on the actual net tangible and intangible assets of American National that exist as of the effective time. Consequently, fair value adjustments and amounts preliminarily allocated to goodwill and identifiable intangibles could change significantly from those allocations used in the unaudited pro forma condensed combined financial statements presented herein and could result in a material change in amortization of acquired intangible assets. In addition, the value of the final merger consideration will be based on the closing price of Atlantic Union common stock on the closing date. For more information, please see the section entitled “Unaudited Pro Forma Condensed Combined Financial Statements.”

The current rising interest rate environment may adversely impact the fair value adjustments of investments and loans acquired in the merger.

Upon the closing of the merger, the combined company will need to adjust the fair value of American National’s investment and loan portfolios. The rising interest rate environment could have the effect of increasing the magnitude of the purchase accounting marks relating to such fair value adjustments, thereby increasing initial tangible book value dilution, extending the tangible book value earn-back period, and negatively impacting the combined company’s capital ratios after completion of the merger.

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THE SPECIAL MEETING

This section contains information for American National shareholders about the special meeting. American National is mailing or otherwise delivering this proxy statement/prospectus to you, as an American National shareholder, on or about October 5, 2023. This proxy statement/prospectus is also being delivered to American National shareholders as Atlantic Union’s prospectus for its offering of Atlantic Union common stock in connection with the merger. This proxy statement/prospectus is accompanied by a notice of the special meeting and a proxy card that the American National board of directors is soliciting for use at the special meeting and at any adjournments or postponements of the special meeting. References to “you” and “your” in this section are to American National shareholders.

Date, Time and Place of the Special Meeting

American National will hold the special meeting at The Wednesday Club, 1002 Main Street, Danville, Virginia 24541, commencing at 10:00 a.m., Eastern Time, on November 14, 2023. On or about October 5, 2023, American National commenced mailing or otherwise delivering this proxy statement/prospectus and a proxy card to its shareholders entitled to vote at the special meeting.

Purpose of the Special Meeting

At the special meeting, American National shareholders will be asked to consider and vote on the following matters:

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the merger proposal;

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the compensation proposal; and

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the adjournment proposal, if necessary or appropriate.

Recommendation of the American National Board of Directors

The American National board of directors has unanimously adopted the merger agreement and approved the transactions contemplated thereby and unanimously recommends that American National shareholders vote “FOR” the merger proposal, “FOR” the compensation proposal and “FOR” the adjournment proposal. Please see the section entitled “The Merger — American National’s Reasons for the Merger and Recommendations of the American National Board of Directors” for a more detailed discussion of the factors considered by the American National board of directors in reaching its decision to adopt the merger agreement and approve the transactions contemplated thereby.

Completion of the mergers is conditioned upon the approval of the merger proposal, but is not conditioned upon the approval of the compensation proposal or, if necessary or appropriate, the adjournment proposal.

Record Date and Quorum

American National has fixed the close of business on September 26, 2023 as the record date to determine which American National shareholders will be entitled to receive notice of and vote at the special meeting. Only American National shareholders of record at the close of business on the record date will be entitled to notice of, and to vote at, the special meeting, or any adjournment or postponement thereof. As of the close of business on the record date, there were 10,629,111 shares of American National common stock outstanding, of which 10,464,449 shares were entitled to notice of, and to vote at, the special meeting, held by approximately 3,760 American National shareholders of record. Each holder of shares of American National common stock outstanding on the record date will be entitled to one vote for each share held of record.

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American National common stock on that date. Such shares cannot be voted at the American National special meeting and are not deemed to be outstanding and entitled to vote for purposes of determining a quorum.

The presence at the special meeting, in person or by proxy, of holders of a majority of the shares of American National common stock outstanding and entitled to vote as of the record date will constitute a quorum for the purposes of the special meeting. All shares of American National common stock entitled to vote and present in person or represented by proxy, including abstentions, if any, will be treated as present for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

If a quorum is not present at the special meeting, it will be postponed until the holders of the number of shares of American National common stock required to constitute a quorum attend. If additional votes must be solicited in order for American National shareholders to approve the merger proposal and the adjournment proposal is approved, the special meeting will be adjourned to solicit additional proxies. The special meeting may be adjourned by the affirmative vote of holders of a majority of the votes cast, even if less than a quorum.

Vote Required; Treatment of Abstentions and Failure to Vote

Shares Held by Directors and Executive Officers

As of the close of business on the record date, there were 10,464,449 shares of American National common stock entitled to vote at the special meeting. As of the close of business on the record date, the directors and executive officers of American National and their affiliates beneficially owned and were entitled to vote approximately 419,414 shares of American National common stock, representing approximately 3.95% of the shares of American National common stock outstanding on that date. American National currently expects that each of its directors and executive officers will vote their shares of American National common stock in favor of the merger proposal and the adjournment proposal. Each of the members of the American National board of directors and certain executive officers of American National, in their capacities as American National shareholders, entered into affiliate agreements in which they agreed to vote their shares of American National common stock in favor of the merger proposal and certain related matters and against alternative transactions. For further information, please see the section entitled “The Merger Agreement — Affiliate Agreements.”

Voting of Proxies; Incomplete Proxies

An American National shareholder may vote by proxy or in person at the special meeting. If you hold your shares of American National common stock in your name as a shareholder of record, you may use one of the following methods to submit a proxy as an American National shareholder:

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through the internet by visiting www.investorvote.com/AMNB and following the instructions, using the control number provided on your proxy card;

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by telephone by calling 1-800-652-VOTE (8683) and following the recorded instructions, using the control number provided on your proxy card; or

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by mail by completing, signing, dating and returning the proxy card in the enclosed envelope, which requires no additional postage if mailed in the United States.

When a properly executed proxy card is returned, the shares of American National common stock represented by it will be voted at the special meeting in accordance with the instructions contained on the proxy card. If any proxy card is returned without indication as to how to vote, the shares of American National common stock represented by the proxy card will be voted as recommended by the American National board of directors.

The deadline for voting by telephone or the internet as a shareholder of record is 5:00 p.m., Eastern Time, on November 13, 2023. For shareholders whose shares are registered in the name of a bank, broker or other nominee, please consult the voting instructions provided by your bank, broker or other nominee for information about the deadline for voting by telephone or the internet.

If an American National shareholder’s shares are held in “street name” by a bank, broker or other nominee, the shareholder should check the voting form used by that firm to determine how to vote. You may not vote shares held in “street name” by returning a proxy card directly to American National or by voting in person at the special meeting unless you provide a “legal proxy,” which you must obtain from your bank, broker or other nominee.

Every American National shareholder’s vote is important. Accordingly, you should complete, sign, date and return the enclosed proxy card, or submit your proxy by telephone or the internet by following the instructions on your proxy card, whether or not you plan to attend the special meeting in person. Submitting a proxy will not prevent you from being able to vote in person at the special meeting.

If your shares are held in “street name” by a bank, broker or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Under stock exchange rules, banks, brokers and other nominees who hold shares of American National common stock in “street name” for a beneficial owner of those shares typically have the authority to vote in their discretion on “routine” proposals when they have not received instructions from beneficial owners. However, banks, brokers and other nominees are not allowed to exercise voting discretion with respect to the approval of matters determined to be “non-routine,” without specific instructions from the beneficial owner. American National expects that all proposals to be voted on at the special meeting will be “non-routine” matters. Broker non-votes are shares held by a bank, broker or other nominee with respect to which such entity is not instructed by the beneficial owner of such shares to vote on the particular proposal and the broker does not have discretionary voting power on such proposal. If your bank, broker or other nominee holds your shares of American National common stock in “street name,” such entity will vote your shares of American National common stock only if you provide instructions on how to vote by complying with the voter instruction form sent to you by your bank, broker or other nominee with this proxy statement/prospectus.

Revocability of Proxies and Changes to an American National Shareholder’s Vote

If you hold stock in your name as a shareholder of record, you may change or revoke your vote or revoke any proxy at any time before it is voted by (i) completing, signing, dating and returning a proxy card with a later date, (ii) voting by telephone or the internet at a later time than your original vote (but before the internet and telephone voting deadline), (iii) delivering a written revocation letter to American National’s corporate secretary, or (iv) attending the special meeting in person, notifying the corporate secretary and voting by ballot at the special meeting. If you choose to send a completed proxy card bearing a later date than your original proxy card, the new proxy card must be received before the beginning of the special meeting.

Any American National shareholder entitled to vote in person at the special meeting may vote in person regardless of whether a proxy has been previously given, but the mere presence (without notifying American National’s corporate secretary) of a shareholder at the special meeting will not constitute revocation of a previously given proxy.

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Written notices of revocation and other communications about revoking your proxy card should be addressed to:

American National Bankshares Inc.
628 Main Street
Danville, Virginia 24541
Attention: Corporate Secretary

If your shares are held in “street name” by a bank, broker or other nominee, you should follow the instructions of your bank, broker or other nominee regarding the change or revocation of voting instructions.

Solicitation of Proxies

American National is soliciting proxies from its shareholders in conjunction with the merger. American National will bear the entire cost of soliciting proxies from its shareholders. In addition to solicitation of proxies by mail, American National will request that banks, brokers and other record holders send proxies and proxy material to the beneficial owners of American National common stock and secure their voting instructions. American National will reimburse the record holders for their reasonable expenses in taking those actions. If necessary, American National may use its directors, officers or employees, who will not be specially compensated, to solicit proxies from American National shareholders, either personally or by telephone, facsimile, letter or electronic means. American National has also made arrangements with Regan & Associates, Inc. to assist it in soliciting proxies for the special meeting and has agreed to pay a flat fee of $34,000, inclusive of all expenses for these services.

Attending the Special Meeting

Subject to space availability, all American National shareholders as of the record date, or their duly appointed proxies, may attend the special meeting. Since seating is limited, admission to the special meeting will be on a first-come, first-served basis. Registration and seating will begin at 9:30 a.m., Eastern Time.

If you hold your shares of American National common stock in your name as a shareholder of record and you wish to attend the special meeting, please bring your proxy card to the special meeting. You should also bring valid photo identification. We encourage you to submit your proxy through the internet or by telephone if possible. When a shareholder submits a proxy through the internet or by telephone, his or her proxy is recorded immediately. If you attend the special meeting, you may also submit your vote in person. Any votes that you previously submitted — whether through the internet, by telephone or by mail — will be superseded by any vote that you cast at the special meeting.

If you are not an American National shareholder of record or if your shares are held in “street name” by a bank, broker or other nominee please bring a letter from the record holder of your shares confirming your beneficial ownership and a valid photo identification in order to be admitted to the meeting. A copy or printout of a brokerage statement will not be sufficient without a signed letter from the bank, broker or other nominee through which you beneficially own American National common stock. American National reserves the right to refuse admittance to anyone without proper proof of share ownership and without valid photo identification.

Assistance

If you need assistance in completing your proxy card, have questions regarding the special meeting, or would like additional copies of this proxy statement/prospectus, please contact American National’s Corporate Secretary at American National Bankshares Inc., 628 Main Street, Danville, Virginia 24541, Attention: Corporate Secretary, or American National’s proxy solicitor, Regan & Associates, Inc., at (800) 737-3426.

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THE AMERICAN NATIONAL PROPOSALS

Proposal 1: Merger Proposal

American National is asking its shareholders to approve the merger agreement under which American National will merge with and into Atlantic Union. For a detailed discussion of the terms and conditions of the merger agreement, please see the section entitled “The Merger Agreement.” American National shareholders should read this proxy statement/prospectus, including any documents incorporated in this proxy statement/prospectus by reference, and its annexes, carefully and in their entirety for more detailed information concerning the merger agreement and the merger. A copy of the merger agreement is attached to this proxy statement/prospectus as Annex A.

As discussed in the section entitled “The Merger — American National’s Reasons for the Merger and Recommendations of the American National Board of Directors,” after careful consideration, the American National board of directors unanimously adopted the merger agreement and approved the transactions contemplated thereby and unanimously declared the merger agreement and the transactions contemplated thereby, including the merger, to be advisable and in the best interest of American National and the American National shareholders.

Required Vote

Approval of the merger proposal requires the affirmative vote of holders of more than two-thirds of the outstanding shares of American National common stock entitled to vote on the merger proposal. If you mark “ABSTAIN” for the merger proposal on your proxy card, fail to either submit a proxy card or vote by telephone or the internet or in person at the special meeting, or are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have the same effect as a vote “AGAINST” the merger proposal.

The American National board of directors unanimously recommends that American National shareholders vote “FOR” the merger proposal.

Proposal 2: Compensation Proposal

In accordance with Section 14A of the Exchange Act, American National is providing its shareholders with the opportunity to cast an advisory (non-binding) vote on the compensation that may be paid or become payable to its named executive officers that is based on or otherwise relates to the merger, the value of which is set forth in the table included in the section of this proxy statement/prospectus entitled “The Merger — Potential Payments and Benefits to American National’s Named Executive Officers in Connection with a Change in Control.” As required by Section 14A of the Exchange Act, American National is asking its shareholders to vote on the adoption of the following resolution:

“RESOLVED, that the compensation that may be paid or become payable to American National’s named executive officers that is based on or otherwise relates to the merger, as disclosed in the table in the section of the proxy statement/prospectus statement entitled “The Merger — Potential Payments and Benefits to American National’s Named Executive Officers in Connection with a Change in Control,” including the associated narrative discussion and the agreements or understandings pursuant to which such compensation may be paid or become payable, are hereby APPROVED.”

The vote on specified compensation that may be payable in connection with the merger is a vote separate and apart from the vote to approve the merger agreement. Accordingly, a shareholder may vote to approve such specified compensation and vote not to approve the merger agreement and vice versa. Because the vote to approve such specified compensation is advisory in nature only, it will not be binding on either American National or Atlantic Union. Accordingly, because American National may be contractually obligated to pay the compensation, the compensation will be payable, subject only to the conditions applicable thereto, if the merger agreement is approved and the merger is completed and regardless of the outcome of the compensational proposal.

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Required Vote

Approval of the compensation proposal requires the affirmative vote of holders of a majority of the votes cast, in person or by proxy, at the special meeting. If you mark “ABSTAIN” for the compensation proposal on your proxy card, fail to either submit a proxy card or vote by telephone or the internet or in person at the special meeting, or are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have no effect on the compensation proposal.

The American National board of directors unanimously recommends a vote “FOR” the compensation proposal.

Proposal 3: Adjournment Proposal

American National is asking its shareholders to approve the adjournment of the special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of the merger proposal if there are insufficient votes at the time of such adjournment to approve the merger proposal.

If, at the special meeting, there is an insufficient number of shares of American National common stock present in person or represented by proxy and voting in favor of the merger proposal, American National will move to adjourn the special meeting in order to enable the American National board of directors to solicit additional proxies for approval of the merger proposal. If the American National shareholders approve the adjournment proposal, American National may adjourn the special meeting and use the additional time to solicit additional proxies, including the solicitation of proxies from American National shareholders who have previously voted. If the date of the adjournment is not announced at the special meeting or a new record date is fixed for the adjourned meeting, a new notice of the adjourned meeting will be given to each shareholder of record entitled to vote at the adjourned meeting, unless the meeting has been adjourned for less than a total of 120 days, in which case no notice of the date, time, place or purposes of such adjourned meeting is required to be given to the shareholders. Even if a quorum is not present, the special meeting may be adjourned by the affirmative vote of holders of a majority of the votes cast.

Required Vote

Approval of the adjournment proposal requires the affirmative vote of holders of a majority of the votes cast, in person or by proxy, at the special meeting. If you mark “ABSTAIN” for the adjournment proposal on your proxy card, fail to either submit a proxy card or vote by telephone or the internet or in person at the special meeting, or are a “street name” holder and fail to instruct your bank, broker or other nominee how to vote, it will have no effect on the adjournment proposal.

The American National board of directors unanimously recommends that American National shareholders vote “FOR” the adjournment proposal.

Other Matters to Come Before the Special Meeting

As of the date of this proxy statement/prospectus, the American National board of directors is not aware of any matters that will be presented for consideration at the special meeting other than as described in this proxy statement/prospectus. If, however, the American National board of directors properly brings any other matters before the special meeting, the persons named in the proxy will vote the shares represented thereby in accordance with the recommendation of the American National board of directors on any such matter (unless the American National shareholder checks the box on the proxy card to withhold discretionary voting authority).

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INFORMATION ABOUT THE COMPANIES

Atlantic Union Bankshares Corporation
4300 Cox Road
Richmond, Virginia 23060
Telephone: (804) 633-5031

As of June 30, 2023, Atlantic Union had total consolidated assets of approximately $20.6 billion, total consolidated loans held for investment, net of deferred fees and costs, of approximately $15.1 billion, total consolidated deposits through Atlantic Union Bank of approximately $16.4 billion, and consolidated shareholders’ equity of approximately $2.4 billion.

For more information about Atlantic Union, see the section entitled “Where You Can Find More Information.”

American National Bankshares Inc.
628 Main Street
Danville, Virginia 24541
Telephone: (434) 792-5111

American National Bankshares Inc. is a one-bank holding company organized under the laws of the Commonwealth of Virginia in 1984. On September 1, 1984, American National acquired all of the outstanding capital stock of American National Bank and Trust Company, a national banking association chartered in 1909 under the laws of the United States. Shares of American National’s common stock are listed on Nasdaq under the symbol “AMNB.”

Headquartered in Danville, Virginia, American National is the parent company of American National Bank and Trust Company. American National Bank and Trust Company is a community bank serving its primary market areas of south central Virginia, the New River Valley and Roanoke, Virginia, and north central North Carolina. American National Bank and Trust Company also manages an additional $1.2 billion of trust, investment and brokerage assets in its Wealth Division.

As of June 30, 2023, American National had total consolidated assets of approximately $3.1 billion, total consolidated loans, net of deferred fees and costs, of approximately $2.2 billion, total consolidated deposits through American National Bank and Trust Company of approximately $2.7 billion, and consolidated shareholders’ equity of approximately $328.0 million.

For more information about American National, see the section entitled “Where You Can find More Information.”

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THE MERGER

The following discussion contains material information regarding the merger. The discussion is subject to, and qualified in its entirety by reference to, the merger agreement, which is attached to this proxy statement/prospectus as Annex A and is incorporated by reference herein. The following is not intended to provide factual information about the parties or any of their respective subsidiaries or affiliates. This discussion does not purport to be complete and may not contain all of the information about the merger that is important to you. We urge you to read carefully this entire proxy statement/prospectus, including the merger agreement, for a more complete understanding of the mergers.

Terms of the Merger

Each of the Atlantic Union board of directors and the American National board of directors has unanimously adopted the merger agreement and approved the transactions contemplated thereby. Under the merger agreement, American National will merge with and into Atlantic Union, with Atlantic Union continuing as the surviving corporation. Immediately following the merger, American National Bank and Trust Company will merge with and into Atlantic Union Bank, with Atlantic Union Bank continuing as the surviving bank.

Atlantic Union will not issue any fractional shares of Atlantic Union common stock in the merger. Instead, an American National shareholder who would otherwise be entitled to receive a fraction of a share of Atlantic Union common stock will receive, in lieu thereof, cash (without interest and rounded to the nearest cent) in an amount determined by multiplying (i) the average closing price by (ii) the fraction of a share (rounded to the nearest one-thousandth when expressed in decimal form) of Atlantic Union common stock which such American National shareholder would otherwise be entitled to receive.

American National shareholders are being asked to approve the merger agreement. See the section entitled “The Merger Agreement” for additional and more detailed information regarding the legal documents that govern the merger, including information about the conditions to completion of the merger and the provisions for terminating or amending the merger agreement.

Background of the Merger

The American National board of directors and American National management have regularly considered and discussed strategic growth and business combination opportunities over the years as part of American National’s ongoing evaluation of its long-term business prospects, objectives and strategies, in order to increase long-term value for its shareholders and support its customers and the communities it serves. These strategies and opportunities have included business combinations, operational enhancements and improvements related to American National’s use of capital through, for example, dividends and repurchases of common stock.

As part of its business strategy and objectives, American National has been an active participant in the mergers and acquisitions market in Virginia, having completed five whole-bank acquisitions since 1996, including two bank mergers since Jeffrey V. Haley became President and Chief Executive Officer in 2013. One of Mr. Haley’s board-approved goals has been to establish and develop relationships with potential merger partners. As a result, the American National board has regularly reviewed potential acquisition and business combination opportunities. Mr. Haley has had, from time to time, informal discussions with representatives of other financial institutions, including Atlantic Union, relating to potential strategic matters, including possible business combination opportunities, and regularly updated the American National board of directors regarding such discussions.

In March and April 2023, Mr. Haley had separate meetings with multiple peer bank chief executive officers to gain perspective from larger and smaller organizations operating in or around American National’s markets. One such meeting occurred on April 7, 2023 with John C. Asbury, President and Chief Executive Officer of Atlantic Union, and involved a high-level discussion about the state of the banking industry and

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the future opportunities and challenges ahead for both companies in light of recent economic events. Messrs. Asbury and Haley shared perspectives on the respective markets, operations and strategies of Atlantic Union and American National. At this meeting, Mr. Asbury informed Mr. Haley that Atlantic Union desired to continue its strategy of growth through acquisitions and was looking for attractive acquisition targets like American National. No specific terms of a potential merger were discussed at the meeting.

To assist in keeping abreast of the state of the banking industry, members of American National management have regularly met with representatives of various investment banking firms experienced in the banking industry to discuss market conditions, current industry trends, American National’s performance and potential business combination opportunities. On several occasions during April 2023, Mr. Haley contacted representatives of KBW to discuss various topics related to the community banking industry and KBW’s observations regarding strategic alternatives potentially available to American National. One potential alternative discussed was American National engaging in a business combination, including a potential merger with a larger organization like Atlantic Union. During these conversations with representatives of KBW, Mr. Haley cited his recent meetings with certain peer bank chief executive officers, including representatives of two larger institutions that in the past expressed interest in American National. Based primarily on Mr. Haley’s meetings with other bank chief executive officers, including Mr. Asbury, and following the discussions with representatives of KBW, Mr. Haley contacted Mr. Asbury in late April 2023 to gauge interest in having a peer-to-peer meeting between management of the two organizations to discuss their companies, operations and cultures in particular and the banking industry in general.

On April 29, 2023, Mr. Haley and Edward C. Martin, Senior Executive Vice President and Chief Administrative Officer of American National, met with Mr. Asbury, and the following additional members of Atlantic Union’s leadership team: Robert M. Gorman, Executive Vice President and Chief Financial Officer; Maria P. Tedesco, Executive Vice President of Atlantic Union and President and Chief Operating Officer of Atlantic Union Bank; Shawn E. O’Brien, Executive Vice President and Consumer and Business Banking Group Executive; David V. Ring, Executive Vice President and Wholesale Banking Group Executive; and David Hartley, Managing Director, Trust and Wealth. The purpose of the meeting was to discuss the corporate culture, business lines, organizational structure and strategic priorities of both companies. At this meeting, the representatives from Atlantic Union informed the representatives of American National that Atlantic Union may be interested in exploring a merger transaction with American National if there was interest in such a transaction. No specific terms of a potential merger were discussed at the meeting.

On May 10, 2023, Mr. Asbury, Mr. Gorman, and Toler F. Cross, Head of Corporate Development & Strategy of Atlantic Union, met with representatives of Atlantic Union’s financial advisor, Piper Sandler & Co., which we refer to as Piper Sandler, to discuss a potential transaction with American National, including reviewing certain financial models of the merger and discussing potential terms of the transaction.

On May 12, 2023, Messrs. Asbury, Gorman, and Cross and representatives of Piper Sandler met with representatives of KBW to discuss Atlantic Union’s preliminary financial analysis of a transaction between Atlantic Union and American National. On May 12, 2023, representatives of KBW relayed Atlantic Union’s preliminary pricing indication to Mr. Haley, which consisted of an all-stock transaction with a proposed fixed exchange ratio in the range of 1.25-1.30 shares of Atlantic Union common stock for each share of American National common stock.

Over the course of May 2023, members of Atlantic Union management held meetings, with representatives of Piper Sandler in attendance, to further discuss the potential transaction with American National.

On May 30, 2023, the capital management committee of the American National board of directors held a special meeting to evaluate American National’s strategic plan, have American National management provide 2023 year-to-date performance information and an updated 2023 forecast, and to discuss short- and long-term strategic options for American National. Messrs. Haley and Martin were present at this meeting as was Jeffrey W. Farrar, Senior Executive Vice President and Chief Operating and Chief Financial Officer of American National. The American National board of directors created the capital management committee in 2014 to assist in fulfilling the American National board of director’s oversight responsibilities with respect to market, interest rate, liquidity and investment risk; capital management; mergers and acquisitions; and dividend and securities related matters. The members of the capital management committee at this time

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were four independent directors of American National: Nancy Howell Agee, Michael P. Haley, Ronda M. Penn and Joel R. Shepherd. All references to Mr. Haley in this section refer to Jeffrey V. Haley, the President and Chief Executive Officer of American National, and not to Michael P. Haley, a director of American National and member of the capital management committee of the American National board of directors.

At the May 30 capital management committee meeting, Mr. Haley reviewed with the capital management committee the following four strategic options for American National: (i) maintain American National’s existing business model and grow organically with minor changes to its operating strategy, including building a greater risk profile; (ii) materially change American National’s business model and operating strategy by making a major investment in one or more fintech companies, buying businesses that provide fee income outside of traditional banking services and/or making a major increase in loan concentration limits; (iii) acquire smaller community banks or partner with a similarly sized financial institution in a merger of equals; and (iv) pursue a strategic merger with a larger financial institution. He also discussed industry shifts, technology adoption by customers, and current merger prospects. Mr. Martin provided a summary of American National’s strategic plan and reviewed 2022 and 2023 year-to-date operational performance and the status of American National’s operations as measured against the goals stated in the strategic plan. Mr. Farrar presented 2023 year-to-date financial performance metrics and an updated 2023 forecast, led a discussion on revenue expectations and operating leverage, and identified the revenue and profit benchmarks likely required for top quartile peer performance in 2023 and several years in the future. Mr. Haley discussed the current challenges faced by banks of similar size to American National and the industry in general. He also shared an overview of recent discussions with chief executive officers of other banks of various sizes since March 2023 and noted management’s view that over the next two to three years, there was an absence of viable acquisition targets that would bring meaningful value to American National’s franchise. Mr. Haley also informed the committee of potential merger of equal partnerships as well as potential acquirers of American National, specifically mentioning Atlantic Union, and reviewed these potential acquirers’ financial metrics, peer comparisons and apparent financial capacity to acquire American National based on publicly available information. The capital management committee engaged in a discussion regarding the current operating environment, the challenges faced by American National in particular and the banking industry in general, and the shifting customer preferences toward digital channels. Questions were raised about the risks associated with American National’s existing strategic plan and its feasibility to maintain its operational strength and successfully achieve the identified financial performance targets in the strategic plan for the foreseeable future given the current and projected market environment. The capital management committee discussed exploring a potential sale of American National due to the challenges faced by American National and the substantial operational transformation that would be required for top quartile peer performance. Given the information presented at this meeting and discussion with management, the capital management committee members concurred that Atlantic Union appeared to be the most suitable merger partner due to the strength of its stock price currency and interest in the American National franchise, as well as the operational familiarity and compatible culture of both companies. The capital management committee then authorized Mr. Haley to call a special board meeting for June 5, 2023 to share with the full American National board of directors the material and information reviewed by the capital management committee.

On June 2, 2023, the executive committee of the Atlantic Union board of directors held a special meeting to discuss Atlantic Union’s interest in a possible acquisition of American National, which was attended by members of Atlantic Union management and representatives of Piper Sandler. During the meeting, the executive committee discussed, amongst itself and with members of Atlantic Union management and representatives of Piper Sandler, strategic considerations relating to a possible acquisition of American National, the results of due diligence conducted to date based on publicly available information, a review of the potential financial impact of the merger, and the potential terms of the merger. At the conclusion of the meeting, the executive committee authorized members of Atlantic Union management to negotiate, execute and deliver a non-binding indication of interest letter to American National with a fixed exchange ratio not to exceed 1.35 shares of Atlantic Union common stock for each share of American National common stock.

On June 5, 2023, the American National board of directors held a special meeting to evaluate and discuss the material and information presented to the capital management committee at its May 30 meeting. Members of American National management gave a similar presentation to the American National board

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of directors as it had for the capital management committee in the May 30 meeting, which included a review of American National’s strategic plan against the current economic landscape and management’s report on short- and long-term strategic options. Mr. Haley led a discussion on the current prospects and developments in the banking industry, the financial markets, the regulatory environment and the implications of the foregoing for banks generally and for American National in particular. The review also included assessments of ongoing consolidation in the banking industry and the benefits and risks to American National and its shareholders of pursuing strategic combinations and sale opportunities as compared to the benefits and risks of continuing to operate as a standalone company. The American National board of directors discussed a number of matters relating to the presentation, including American National’s efforts to successfully acquire in strategic markets and the related complications in doing so, the difficulty in obtaining the needed level of growth organically, American National’s creation of good value to date combined with the current presence of interested buyers, the apparent financial capacity of a select number of likely interested buyers to acquire American National on financial terms that American National might accept, and the fit of American National and each potential acquirer culturally and geographically. After considering the above matters, the American National board of directors authorized members of American National management to continue discussions with Atlantic Union about a possible merger of the companies and authorized members of American National management to continue to work with KBW as American National’s financial advisor with respect to a merger with Atlantic Union.

On June 6, 2023, Mr. Haley contacted representatives of KBW to discuss a possible transaction with Atlantic Union. Among other matters, Mr. Haley directed KBW to contact Piper Sandler to request that Atlantic Union increase its preliminary pricing to an exchange ratio of 1.35 shares of Atlantic Union common stock for each share of American National common stock. KBW relayed the request for increasing the exchange ratio to Piper Sandler the same day.

On June 7, 2023, Mr. Asbury and Ronald L. Tillett, Chairman of the Atlantic Union board of directors, met with Mr. Haley to discuss the potential merger and recent developments at their respective companies. During this meeting, the parties reviewed each institution’s operations, financial performance, recent experience in merger transactions, and the strategic rationale for Atlantic Union’s potential acquisition of American National. Terms for a possible merger were discussed, including an all-stock transaction with a fixed exchange ratio and two board seats for American National representatives on the Atlantic Union board of directors subject to certain corporate governance requirements. The parties acknowledged American National’s request of June 6, 2023 to increase the exchange ratio to 1.35 but did not commit or come to any agreement on any specific pricing information or exchange ratio at this meeting. Mr. Asbury noted that Atlantic Union would be prepared to deliver a non-binding indication of interest letter in the following week if Mr. Haley believed that American National would have interest in exploring a transaction with Atlantic Union. Mr. Haley stated that, based on the most recent meeting of the American National board of directors, he believed that American National was interested in continuing merger discussions and he would ask American National’s capital management committee to meet to review the non-binding indication of interest letter as soon as practicable upon receipt.

On June 8, 2023, Atlantic Union and American National signed a mutual confidentiality agreement and began to exchange confidential information to facilitate the companies’ respective due diligence. During the period June 8, 2023 through July 24, 2023, representatives of Atlantic Union and American National and their respective financial and legal advisors communicated by phone and other electronic means to review business, financial and other information regarding each company. During these meetings, members of management of each of the companies and their advisors engaged in a series of discussions and asked and answered questions regarding each company’s respective businesses.

On June 9, 2023, the capital management committee of the American National board of directors held a special meeting at which Mr. Haley reported the matters discussed at the June 7, 2023 meeting with representatives of Atlantic Union. Mr. Haley stated that Atlantic Union would be submitting a non-binding indication of interest letter for a proposed merger transaction in the following days. The committee members agreed to meet promptly following receipt of Atlantic Union’s non-binding indication of interest. Representatives of KBW and Williams Mullen, American National’s legal counsel, attended the meeting and provided observations regarding the anticipated merger process and timeline.

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On June 12, 2023, Atlantic Union submitted a non-binding indication of interest letter for the merger of American National into Atlantic Union in an all-stock transaction that set forth, among other things, a proposed exchange ratio of 1.35 shares of Atlantic Union common stock for each share of American National common stock and a 60-day exclusivity covenant from American National, subject to renewal for an additional 30-day period. The non-binding indication of interest letter also provided that up to two current directors of American National be appointed to serve on Atlantic Union’s board of directors subject to certain corporate governance requirements. Based on the closing price of Atlantic Union common stock of $28.86 per share on June 9, 2023, the 1.35 exchange ratio represented an implied value of $38.96 per share of American National common stock, and a 27.4% premium to American National’s closing price of $30.58 on June 9, 2023.

On June 14, 2023, the capital management committee of the American National board of directors convened a special meeting to discuss the non-binding indication of interest letter from Atlantic Union. Representatives of KBW and Williams Mullen attended the meeting, as did Messrs. Farrar, Haley and Martin. Representatives of KBW reviewed the exchange ratio with the capital management committee. The other terms of the non-binding indication of interest letter were also reviewed with the capital management committee by the American National management team and representatives of Williams Mullen and KBW. Members of the capital management committee inquired about the terms of the non-binding indication of interest letter and discussed its contents with meeting participants. Based on those discussions, the committee concluded that the exchange ratio was attractive and that moving forward with a merger with Atlantic Union was in the best interest of American National shareholders. The capital management committee directed that American National, through KBW, request certain modifications to the non-binding indication of interest letter, including those relating to severance payments to employees who would not be retained after the merger, indemnification and insurance for officers and directors of American National after the merger, and shortening the exclusivity period for negotiating a definitive merger agreement. Such revised non-binding indication of interest letter was delivered to Atlantic Union on June 15, 2023.

On June 15, 2023, the Atlantic Union board of directors held a meeting, which was attended by members of Atlantic Union management and representatives of Piper Sandler. At the meeting, members of Atlantic Union management reviewed the status of negotiations with American National, including the above-described changes requested by American National to the non-binding indication of interest letter, and the results of Atlantic Union’s due diligence of American National to date. Representatives of Piper Sandler then discussed, among other matters, certain financial information of Atlantic Union and American National, and reviewed certain preliminary financial analyses regarding the transaction at the proposed 1.35 exchange ratio. During the meeting, the Atlantic Union board of directors also authorized the corporate development advisory committee of the Atlantic Union board of directors, a committee composed solely of independent directors, to receive updates regarding due diligence and to advise Atlantic Union management on the merger.

On June 16, 2023, Atlantic Union delivered to American National a revised non-binding indication of interest letter that incorporated the above-described changes requested by American National. Other than these changes, the material transaction terms set forth in the revised non-binding indication of interest letter remained unchanged from the initial non-binding indication of interest letter submitted by Atlantic Union on June 12, 2023.

On June 16, 2023, American National granted access to its electronic data room to Atlantic Union and its advisors to facilitate Atlantic Union’s due diligence review of American National.

On June 22, 2023, the American National board of directors held a special meeting at which Atlantic Union’s revised non-binding indication of interest letter and the proposed merger were discussed. Messrs. Farrar and Martin and representatives of KBW and Williams Mullen were also in attendance at the meeting. Representatives of Williams Mullen reviewed the terms of the revised non-binding indication of interest letter. Representatives of KBW discussed the current bank mergers and acquisitions environment, American National’s potentially available strategic options and preliminary valuation matters. Representatives of KBW also provided a preliminary financial overview of the proposed merger transaction, including financial highlights, demographic information and pro forma loan and deposit composition, based on publicly available information on the parties and the proposed 1.35 exchange ratio. Based on the closing price of Atlantic Union common stock of $29.01 per share on June 16, 2023, the 1.35 exchange ratio represented an

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implied value of $39.16 per share of American National common stock, and a 27.6% premium to American National’s closing price of $30.70 on June 16, 2023. Representatives of KBW reviewed with the American National board of directors publicly available information regarding pricing metrics of transactions announced since December 31, 2020 involving other banking institutions nationally and also provided observations regarding certain other potential acquirers’ apparent financial capacity to acquire American National based on publicly available information, and the board considered such information. Representatives of KBW and Williams Mullen then discussed with the American National board of directors a proposed timeline and steps to be taken towards entering into a definitive merger agreement with Atlantic Union.

At the June 22, 2023 meeting, the American National board of directors discussed the potential benefits and risks of a merger with Atlantic Union, and engaged in a thorough discussion on the potential combination with Atlantic Union, especially the proposed exchange ratio. The American National board of directors also considered, in general, the impact of the proposed transaction on American National’s management, employees and communities it serves. The American National board of directors reviewed the financial performance, stock performance, market position, growth prospects and other matters concerning Atlantic Union. After a lengthy discussion, the American National board of directors determined that a merger with Atlantic Union would provide substantial long-term benefits to American National’s shareholders. The American National board of directors then authorized management to proceed with the negotiation of a definitive merger agreement and related documents with Atlantic Union.

After the American National board meeting, Mr. Haley contacted Mr. Asbury to inform him that the American National board had determined to move forward in merger discussions with Atlantic Union, and executed and delivered the revised non-binding indication of interest letter to Mr. Asbury. The non-binding indication of interest letter contained a 45-day exclusivity covenant for American National, subject to renewal for an additional 30-day period.

On July 7, 2023, representatives of Covington, Atlantic Union’s legal counsel, provided representatives of Williams Mullen with a draft merger agreement. Until execution on July 24, 2023, Atlantic Union and American National, with the assistance of their legal advisors, continued to negotiate the outstanding terms of the merger agreement and related transaction documents, including the affiliate agreements, disclosure schedules and certain agreements between Atlantic Union and Mr. Haley as described in the section entitled “— Interests of American National’s Directors and Executive Officers in the Merger — Agreements between Mr. Haley and Atlantic Union Bank.”

On July 7, 2023, the corporate development advisory committee of the Atlantic Union board of directors held a meeting, which was attended by members of Atlantic Union management and representatives of Piper Sandler. Members of Atlantic Union management updated the corporate development advisory committee on the status, process and preliminary findings of Atlantic Union’s ongoing due diligence of American National, and discussed the anticipated impact of the transaction on the combined company, including the expected impact on key financial metrics.

On July 14, 2023, the corporate development advisory committee of the Atlantic Union board of directors held a meeting, which was attended by members of Atlantic Union management and representatives of Piper Sandler. Members of Atlantic Union management reported on the results of Atlantic Union’s due diligence of American National, which had been substantially completed, and provided an update on each company’s quarter-end financial results. Representatives of Piper Sandler discussed with the corporate development advisory committee, among other things, a summary of the financial terms of the transaction, including the potential impact of the transaction on the combined company and the possible impact on certain key financial metrics. Following a discussion, the corporate development advisory committee recommended that the Atlantic Union board of directors review the merger for approval and authorized Atlantic Union management to continue their negotiation of the merger agreement.

On July 18, 2023, the American National board of directors held a regularly scheduled meeting to discuss the current status of the merger and received updates from members of American National management and representatives of KBW and Williams Mullen. Members of management discussed aspects of Atlantic Union’s due diligence of American National and American National’s reverse due diligence of Atlantic Union. Members of management and representatives of Williams Mullen and KBW discussed the current negotiations and the status of the proposed merger agreement, the preparation of

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disclosure schedules to the merger agreement and the current proposed merger consideration, including the exchange ratio. The American National board of directors discussed the merger and the proposed merger agreement and asked for additional negotiation of certain key terms, particularly with respect to deal protection and termination rights. The American National board of directors, members of management and representatives of KBW and Williams Mullen discussed timing and next steps, which included the completion and resolution of due diligence and the merger agreement and formal approval from the American National board of directors. In addition, Mr. Asbury and Ms. Tedesco attended a portion of the meeting to discuss Atlantic Union’s history, strategy and rationale for pursuing a combination with American National.

On July 22, 2023, the American National board of directors held a special meeting with members of management and representatives of American National’s financial and legal advisors in attendance, to discuss the proposed transaction and review the terms of the proposed merger agreement and merger. Prior to such meeting, the American National board of directors was provided with copies of the latest draft versions of the merger agreement, the plan of merger, the bank merger agreement and the affiliate agreements, and a summary of the material terms of the merger agreement and related documents prepared by Williams Mullen. Members of management reviewed for the American National board of directors the progress of negotiations with Atlantic Union and reported on the status of its reverse due diligence investigation of Atlantic Union. At the meeting, representatives of Williams Mullen discussed with the American National board of directors the fiduciary duty legal standards applicable to its decisions and actions with respect to its consideration of the merger, including the applicable standard of director conduct under Virginia law, and reviewed in detail the legal terms of the proposed merger agreement and related transaction documents. KBW also reviewed certain financial aspects of the proposed merger and preliminarily discussed the opinion expected to be delivered by KBW with respect to the fairness, from a financial point of view, of the exchange ratio in the merger. Members of Williams Mullen and KBW responded to questions from the board regarding the proposed merger and the draft merger agreement and related documents. After review and thorough discussion among members of the American National board of directors, including consideration of the factors described under “— American National’s Reasons for the Merger and Recommendation of the American National Board of Directors,” the American National board of directors determined to hold a meeting on July 24 to further consider the merger.

On July 24, 2023, the American National board of directors held a special meeting at which updates on the merger negotiations were provided by members of American National management. Prior to such meeting, the American National board of directors was provided with the financial presentation materials prepared by KBW. Representatives of Williams Mullen briefed the American National board of directors on its discussions with Covington and the changes to the merger agreement and related documents from the draft merger agreement and related documents previously reviewed on July 22, 2023. At this meeting, KBW reviewed the financial aspects of the merger and rendered to the American National board of directors an opinion (which was initially rendered verbally and then confirmed in a written opinion, dated July 24, 2023, a copy of which is attached to this proxy statement/prospectus as Annex C) to the effect that, as of such date and subject to the procedures followed, assumptions made, matters considered, and qualifications and limitations on the review undertaken by KBW as set forth in its opinion, the exchange ratio in the merger was fair, from a financial point of view, to the holders of American National common stock. The American National board of directors engaged in a substantive discussion on the merger, the terms of the merger agreement and related documents and the presentation by KBW. American National board members presented questions to members of American National management and representatives of Williams Mullen and KBW regarding the merger and the merger agreement, and such members and representatives responded to the inquiries. After further discussion of the terms of the merger, including consideration of the factors described under “— American National’s Reasons for the Merger and Recommendation of the American National Board of Directors,” the American National board of directors determined that the merger agreement, including the mergers and the transactions contemplated thereby, were advisable and in the best interest of American National and its shareholders. The board voted unanimously to adopt the merger agreement and approve the mergers and the other transactions contemplated by the merger agreement.

On July 24, 2023, the Atlantic Union board of directors held a special meeting, held jointly with a special meeting of the Atlantic Union Bank board of directors, to consider the terms of the merger and merger agreement. Before such meeting, the Atlantic Union board of directors was provided with copies of the latest draft versions of the merger agreement, the plan of merger, the bank merger agreement and the

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affiliate agreements, and a summary of the material terms of the merger agreement and the affiliate agreements and related documents prepared by Covington. At the meeting, members of Atlantic Union management reported on the results of Atlantic Union’s due diligence and the status of negotiations with American National. Also at the meeting, representatives of Piper Sandler reviewed with the Atlantic Union board of directors the financial aspects of the merger. At the meeting, representatives of Covington reviewed with the Atlantic Union board of directors its fiduciary duties in the context of the merger and reviewed the key terms of the merger agreement and related agreements (including the affiliate agreements), as described elsewhere in this proxy statement/prospectus, including a summary of the provisions relating to governance of the combined company and the provisions relating to employee matters. Atlantic Union board members presented questions to members of Atlantic Union management and representatives of Covington and its financial advisor regarding the merger and the merger agreement, and such members and representatives responded to the inquiries. After considering the proposed terms of the merger agreement, the terms of the affiliate agreements, and taking into consideration the matters discussed during that meeting and prior meetings of the Atlantic Union board of directors, including the factors described in the section entitled “— Atlantic Union’s Reasons for the Merger,” the Atlantic Union board of directors determined that the merger agreement, including the mergers and the other transactions contemplated thereby, were consistent with Atlantic Union’s business strategies, advisable and in the best interests of Atlantic Union and Atlantic Union shareholders and the Atlantic Union board of directors voted to unanimously adopt the merger agreement, and approve the mergers and the other transactions contemplated by the merger agreement.

Following the board meetings of Atlantic Union and American National on July 24, 2023, and after finalizing the merger agreement, Atlantic Union and American National executed the merger agreement, and each of the directors and certain executive officers of American National executed affiliate agreements. On the morning of July 25, 2023, Atlantic Union and American National issued a joint press release announcing the execution of the merger agreement.

American National’s Reasons for the Merger and Recommendation of the American National Board of Directors

After careful consideration, at a meeting held on July 24, 2023, the American National board of directors unanimously determined that the merger agreement, including the merger and the other transactions contemplated thereby, is advisable and in the best interest of American National and its shareholders. Accordingly, the American National board of directors unanimously adopted the merger agreement and approved the transactions contemplated thereby, including the merger, and unanimously recommends that the American National shareholders vote “FOR” the merger proposal.

In reaching its decision to adopt the merger agreement and approve the transactions contemplated thereby, including the merger, and recommend that the American National shareholders approve the merger proposal, the American National board of directors evaluated the merger and the merger agreement in consultation with American National’s management, as well as American National’s financial and legal advisors, and considered a number of factors, including, without limitation, the following material factors, which are not presented in order of importance:

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the review undertaken by the American National board of directors and management with respect to the strategic alternatives available to American National, including remaining independent and growing organically or engaging in alternative strategic merger transactions;

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the business strategy of American National and its prospects for the future as an independent institution, including the risks inherent in successful execution of its strategic plan and its projected financial results;

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the challenges facing American National in the current competitive, economic, financial and regulatory climate, including evolving trends in technology and increasing nationwide and global competition, and the potential benefits of aligning American National with a larger organization;

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the consistency of the merger with American National’s long-term strategic plan to seek profitable future expansion, leading to opportunities for growth in overall shareholder value and enhanced liquidity for the American National shareholders;

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each of American National’s, Atlantic Union’s and the combined company’s business, operations, financial condition, asset quality, earnings and prospects;

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the terms of the merger agreement, including the fixed exchange ratio, expected tax treatment, deal protection and termination fee provisions, which the American National board of directors reviewed with American National’s management and American National’s outside legal and financial advisors;

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the fact that the transaction value would be approximately $430.9 million, with an implied value of $40.55 per share of American National common stock based on the closing price of Atlantic Union common stock of $30.04 per share on July 21, 2023;

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the value of the merger consideration relative to the market value, book value, tangible book value, earnings and projected earnings of American National;

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the expected receipt by the American National shareholders, after the effective time, of dividends declared and paid by Atlantic Union on its common stock consistent with historical levels and trends that, taking into account the exchange ratio, would be higher than dividends declared and paid by American National on its common stock consistent with historical levels and trends;

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the greater market capitalization and trading liquidity of Atlantic Union common stock;

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the potential for the combined entity to have greater future earnings and prospects compared to American National’s earnings and prospects on an independent basis due to greater operating efficiencies and better penetration of commercial and consumer markets;

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the ability of Atlantic Union to complete a merger transaction with American National from a financial and regulatory perspective, including Atlantic Union’s prior history of successful merger transactions;

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the strong capital positions maintained by Atlantic Union and American National before the merger and the anticipated strong capital position for the combined company following the merger;

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the benefits to American National and its customers of operating as a larger organization, including enhancements in products and services, higher lending limits, and greater financial resources;

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the compatibility and complementary nature of the American National and Atlantic Union businesses and cultures, including customer focus, geographic coverage, business operations and management operating styles;

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the long- and short-term interests of American National and its shareholders, and the interests of American National’s employees, customers and the communities in which American National maintains offices;

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the likelihood of realizing the strategic benefits of the merger that the American National board of directors believes will result from the continuity provided to the American National shareholders by the corporate governance aspects of the merger, including the appointment at the effective time of two current members of the American National board of directors, Nancy Howell Agee and Joel R. Shepherd, as directors of each of Atlantic Union and Atlantic Union Bank;

•

the opinion, dated July 24, 2023, of KBW to the American National board of directors as to the fairness, from a financial point of view and as of the date of the opinion, to the holders of American National common stock of the exchange ratio in the merger, as more fully described below under “— Opinion of American National’s Financial Advisor;”

•

the fact that American National would be prohibited from soliciting or, subject to certain exceptions, entering into discussions with any third party regarding, any acquisition proposal or offers for competing transactions after execution of the merger agreement, and the possibility that, while it was not viewed as precluding other proposals, the $17,232,000 termination fee payable to Atlantic Union if the merger agreement is terminated under certain circumstances could potentially discourage other companies from pursuing, announcing or submitting a business combination proposal to American National that might result in greater value to the American National shareholders;

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•

the risk that, because the exchange ratio is fixed, the value of the shares of Atlantic Union that the American National shareholders receive in the merger could be adversely affected by a decrease in the trading price of Atlantic Union common stock before the effective time;

•

the risk that potential benefits and synergies sought in the merger may not be realized or may not be realized within the expected time period;

•

the fact that, while the merger is pending, American National will be subject to certain customary restrictions on the conduct of its business, which may delay or prevent it from pursuing business opportunities that may arise, or preclude it from taking actions that it would otherwise take absent the pending merger;

•

the potential challenges of integrating American National’s businesses, operations and employees with those of Atlantic Union, including the costs associated with such integration;

•

the effects of the merger on American National employees, including the prospects for continued employment in a larger organization and various benefits agreed to be provided to American National employees;

•

the possibility that the merger and the integration process could result in employee attrition and have a negative effect on business and customer relationships of American National;

•

the fact that, while American National expects that the merger will be completed, there can be no assurance that all conditions to the parties’ obligations to complete the merger will be satisfied, including the risk that certain regulatory approvals or approval of the American National shareholders, the receipt of which are conditions to the completion of the merger, might not be obtained, and, as a result, the merger may not be completed;

•

the potential risk of diverting management attention and resources from the operation of American National’s business and towards completion of the merger;

•

anticipated substantial costs even if the merger is not completed;

•

the fact that certain of American National’s directors and executive officers have interests in the merger that are different from, or in addition to, the interests of other American National shareholders. See “— Interests of American National’s Directors and Executive Officers in the Merger;”

•

the significant risks and costs involved in connection with entering into and completing the merger, or failing to complete the merger in a timely manner, or at all;

•

the challenges in absorbing the effect of any failure to complete the merger, including the potential existence of a tail period for the termination fee and market reactions; and

•

the possibility of litigation in connection with the merger.

The foregoing discussion of the factors considered by the American National board of directors is not intended to be exhaustive, but, rather, includes the material factors considered by the American National board of directors. In reaching its decision to adopt the merger agreement and approve the transactions contemplated thereby, including the merger, the American National board of directors did not quantify or assign any relative weights to the factors considered, and individual directors may have given different weights to different factors. The American National board of directors considered all these factors as a whole, including through discussion with, and questioning of, American National’s management and American National’s financial and legal advisors, and overall considered the factors to be favorable to, and to support, its determination to adopt the merger agreement and approve the transactions contemplated thereby, including the merger.

For the reasons set forth above, the American National board of directors unanimously adopted the merger agreement and approved the transactions contemplated thereby, determined that the merger is advisable and in the best interest of American National and its shareholders and unanimously recommends that the American National shareholders vote “FOR” the merger proposal.

This explanation of the American National board of directors’ reasoning and all other information presented in this section is forward-looking in nature and, therefore, should be read in light of the factors discussed in the section entitled “Cautionary Statement Regarding Forward-Looking Statements.”

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Opinion of American National’s Financial Advisor

American National engaged KBW to render financial advisory and investment banking services to American National, including an opinion to the American National board of directors as to the fairness, from a financial point of view, to the holders of American National common stock of the exchange ratio. American National selected KBW because KBW is a nationally recognized investment banking firm with substantial experience in transactions similar to the merger. As part of its investment banking business, KBW is continually engaged in the valuation of financial services businesses and their securities in connection with mergers and acquisitions.

As part of KBW’s engagement, representatives of KBW attended the meeting of the American National board of directors held on July 24, 2023, at which the American National board of directors evaluated the merger. At this meeting, KBW reviewed the financial aspects of the merger and rendered to the American National board of directors an opinion to the effect that, as of such date and subject to the procedures followed, assumptions made, matters considered, and qualifications and limitations on the review undertaken by KBW as set forth in its opinion, the exchange ratio was fair, from a financial point of view, to the holders of American National common stock. The American National board of directors unanimously adopted the merger agreement and approved the transactions contemplated thereby at this meeting.

The description of the opinion set forth herein is qualified in its entirety by reference to the full text of the opinion, which is attached as Annex C to this proxy statement/prospectus and is incorporated herein by reference, and describes the procedures followed, assumptions made, matters considered, and qualifications and limitations on the review undertaken by KBW in preparing the opinion.

KBW’s opinion speaks only as of the date of the opinion. The opinion was for the information of, and was directed to, the American National board of directors (in its capacity as such) in connection with its consideration of the financial terms of the merger. The opinion addressed only the fairness, from a financial point of view, to the holders of American National common stock of the exchange ratio. It did not address the underlying business decision of American National to engage in the merger or enter into the merger agreement or constitute a recommendation to the American National board of directors in connection with the merger, and it does not constitute a recommendation to any holder of American National common stock or any shareholder of any other entity as to how to vote in connection with the merger or any other matter, nor does it constitute a recommendation regarding whether or not any such shareholder should enter into a voting, shareholders’ or affiliates’ agreement with respect to the merger.

KBW’s opinion was reviewed and approved by KBW’s Fairness Opinion Committee in conformity with its policies and procedures established under the requirements of Rule 5150 of the Financial Industry Regulatory Authority.

In connection with the opinion, KBW reviewed, analyzed and relied upon material bearing upon the financial and operating condition of American National and Atlantic Union and bearing upon the merger, including, among other things, the following:

•

a draft of the merger agreement dated July 20, 2023 (the most recent draft then made available to KBW);

•

the audited financial statements and Annual Reports on Form 10-K for the three fiscal years ended December 31, 2022 of American National;

•

the unaudited quarterly financial statements and Quarterly Report on Form 10-Q for the quarter ended March 31, 2023 of American National;

•

certain preliminary draft and unaudited financial results for the quarter ended June 30, 2023 of American National (provided by American National);

•

the audited financial statements and Annual Reports on Form 10-K for the three fiscal years ended December 31, 2022 of Atlantic Union;

•

the unaudited quarterly financial statements and Quarterly Report on Form 10-Q for the quarter ended March 31, 2023 of Atlantic Union;

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•

certain preliminary draft and unaudited financial results for the quarter ended June 30, 2023 of Atlantic Union (provided by Atlantic Union);

•

certain publicly available regulatory filings of American National and Atlantic Union and their respective subsidiaries, including as applicable, the quarterly reports on Form FR Y-9C and the quarterly call reports required to be filed (as the case may be) with respect to each quarter during the three-year period ended December 31, 2022 and the quarter ended March 31, 2023;

•

certain other interim reports and other communications of American National and Atlantic Union to their respective shareholders; and

•

other financial information concerning the businesses and operations of American National and Atlantic Union furnished to KBW by American National and Atlantic Union or that KBW was otherwise directed to use for purposes of KBW’s analyses.

KBW’s consideration of financial information and other factors that it deemed appropriate under the circumstances or relevant to its analyses included, among others, the following:

•

the historical and current financial position and results of operations of American National and Atlantic Union;

•

the assets and liabilities of American National and Atlantic Union;

•

the nature and terms of certain other merger transactions and business combinations in the banking industry;

•

a comparison of certain financial and stock market information for American National and Atlantic Union with similar information for certain other companies the securities of which were publicly traded;

•

financial and operating forecasts and projections of American National that were provided to and discussed with KBW by American National management, and used and relied upon by KBW at the direction of such management and with the consent of the American National board of directors;

•

publicly available consensus “street estimates” of Atlantic Union, as well as assumed long-term Atlantic Union growth rates provided to KBW by Atlantic Union management, all of which information was discussed with KBW by Atlantic Union management and used and relied upon by KBW based on such discussions, at the direction of American National management and with the consent of the American National board of directors; and

•

estimates regarding certain pro forma financial effects of the merger on Atlantic Union (including, without limitation, the cost savings expected to result or be derived from the merger) that were provided to and discussed with KBW by Atlantic Union management, and used and relied upon by KBW based on such discussions, at the direction of American National management and with the consent of the American National board of directors.

KBW also performed such other studies and analyses as it considered appropriate and took into account its assessment of general economic, market and financial conditions and its experience in other transactions, as well as its experience in securities valuation and knowledge of the banking industry generally. KBW also participated in discussions held by the managements of American National and Atlantic Union regarding the past and current business operations, regulatory relations, financial condition and future prospects of their respective companies and such other matters as KBW deemed relevant to its inquiry. KBW was not requested to assist, and did not assist, American National with soliciting indications of interest from third parties regarding a potential transaction with American National.

In conducting its review and arriving at its opinion, KBW relied upon and assumed the accuracy and completeness of all of the financial and other information that was provided to or discussed with it or that was publicly available and KBW did not independently verify the accuracy or completeness of any such information or assume any responsibility or liability for such verification, accuracy or completeness. KBW relied upon the management of American National as to the reasonableness and achievability of the financial and operating forecasts and projections of American National referred to above (and the assumptions and bases therefor), and KBW assumed that such forecasts and projections represented the best currently

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available estimates and judgments of such management and that such forecasts and projections would be realized in the amounts and in the time periods estimated by such management. KBW further relied, with the consent of American National, upon Atlantic Union management as to the reasonableness and achievability of the publicly available consensus “street estimates” of Atlantic Union, the assumed long-term Atlantic Union growth rates, and the estimates regarding certain pro forma financial effects of the merger on Atlantic Union (including, without limitation, the cost savings expected to result or be derived from the merger), all as referred to above (and the assumptions and bases for all such information), and KBW assumed that all such information represented, or in the case of the Atlantic Union “street estimates” referred to above that such estimates were consistent with, the best currently available estimates and judgments of Atlantic Union management and that the forecasts, projections and estimates reflected in such information would be realized in the amounts and in the time periods estimated.

It is understood that the portion of the foregoing financial information of American National and Atlantic Union that was provided to KBW was not prepared with the expectation of public disclosure and that all of the foregoing financial information, including the publicly available consensus “street estimates” of Atlantic Union referred to above, was based on numerous variables and assumptions that are inherently uncertain (including, without limitation, factors related to general economic and competitive conditions and, in particular, the widespread disruption, extraordinary uncertainty and unusual volatility arising from global tensions and political unrest, economic uncertainty, inflation, rising interest rates, the COVID-19 pandemic and, in the case of the banking industry, recent actual or threatened regional bank failures, including the effect of evolving governmental interventions and non-interventions) and, accordingly, actual results could vary significantly from those set forth in such information. KBW assumed, based on discussions with the respective managements of American National and Atlantic Union and with the consent of the American National board of directors, that all such information provided a reasonable basis upon which KBW could form its opinion and KBW expressed no view as to any such information or the assumptions or bases therefor. KBW relied on all such information without independent verification or analysis and did not in any respect assume any responsibility or liability for the accuracy or completeness thereof.

KBW also assumed that there were no material changes in the assets, liabilities, financial condition, results of operations, business or prospects of either American National or Atlantic Union since the date of the last financial statements of each such entity that were made available to KBW. KBW is not an expert in the independent verification of the adequacy of allowances for loan and lease losses and KBW assumed, without independent verification and with American National’s consent, that the aggregate allowances for loan and lease losses for each of American National and Atlantic Union are adequate to cover such losses. In rendering its opinion, KBW did not make or obtain any evaluations or appraisals or physical inspection of the property, assets or liabilities (contingent or otherwise) of American National or Atlantic Union, the collateral securing any of such assets or liabilities, or the collectability of any such assets, nor did KBW examine any individual loan or credit files, nor did it evaluate the solvency, financial capability or fair value of American National or Atlantic Union under any state or federal laws, including those relating to bankruptcy, insolvency or other matters. KBW made note of the classification by each of American National and Atlantic Union of its loans and owned securities as either held to maturity or held for investment, on the one hand, or held for sale, on the other hand, and also reviewed reported fair value marks-to-market and other reported valuation information, if any, relating to such loans or owned securities contained in the respective financial statements of American National and Atlantic Union, but KBW expressed no view as to any such matters. Estimates of values of companies and assets do not purport to be appraisals or necessarily reflect the prices at which companies or assets may actually be sold. Such estimates are inherently subject to uncertainty and should not be taken as KBW’s view of the actual value of any companies or assets.

KBW assumed, in all respects material to its analyses, the following:

•

that the merger and any related transactions (including, without limitation the bank merger) would be completed substantially in accordance with the terms set forth in the merger agreement (the final terms of which KBW assumed would not differ in any respect material to KBW’s analyses from the draft reviewed by KBW and referred to above), with no adjustments to the exchange ratio and with no other consideration or payments in respect of American National common stock;

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•

that the representations and warranties of each party in the merger agreement and in all related documents and instruments referred to in the merger agreement were true and correct;

•

that each party to the merger agreement and all related documents would perform all of the covenants and agreements required to be performed by such party under such documents;

•

that there were no factors that would delay or subject to any adverse conditions, any necessary regulatory or governmental approval for the merger or any related transactions and that all conditions to the completion of the merger and any related transactions would be satisfied without any waivers or modifications to the merger agreement or any of the related documents; and

•

that in the course of obtaining the necessary regulatory, contractual, or other consents or approvals for the merger and any related transactions, no restrictions, including any divestiture requirements, termination or other payments or amendments or modifications, would be imposed that would have a material adverse effect on the future results of operations or financial condition of American National, Atlantic Union or the pro forma entity, or the contemplated benefits of the merger, including without limitation the cost savings expected to result or be derived from the merger.

KBW assumed that the merger would be consummated in a manner that complies with the applicable provisions of the Securities Act, the Exchange Act, and all other applicable federal and state statutes, rules and regulations. KBW was further advised by representatives of American National that American National relied upon advice from its advisors (other than KBW) or other appropriate sources as to all legal, financial reporting, tax, accounting and regulatory matters with respect to American National, Atlantic Union, the merger and any related transaction, and the merger agreement. KBW did not provide advice with respect to any such matters.

KBW’s opinion addressed only the fairness, from a financial point of view, as of the date of the opinion, of the exchange ratio to the holders of American National common stock. KBW expressed no view or opinion as to any other terms or aspects of the merger or any term or aspect of any related transactions (including the bank merger), including without limitation, the form or structure of the merger or any such related transaction, any consequences of the merger or any such related transaction to American National, its shareholders, creditors or otherwise, or any terms, aspects, merits or implications of any employment, consulting, voting, support, shareholder or other agreements, arrangements or understandings contemplated or entered into in connection with the merger or otherwise. KBW’s opinion was necessarily based upon conditions as they existed and could be evaluated on the date of such opinion and the information made available to KBW through the date of such opinion. There is currently significant volatility in the stock and other financial markets arising from global tensions and political unrest, economic uncertainty, inflation, rising interest rates, the COVID-19 pandemic and, in the case of the banking industry, recent actual or threatened regional bank failures, including the effect of evolving governmental interventions and non-interventions. Developments subsequent to the date of KBW’s opinion may have affected, and may affect, the conclusion reached in KBW’s opinion and KBW did not and does not have an obligation to update, revise or reaffirm its opinion. KBW’s opinion did not address, and KBW expressed no view or opinion with respect to:

•

the underlying business decision of American National to engage in the merger or enter into the merger agreement;

•

the relative merits of the merger as compared to any strategic alternatives that are, have been or may be available to or contemplated by American National or the American National board of directors;

•

the fairness of the amount or nature of any compensation to any of American National’s officers, directors or employees, or any class of such persons, relative to the compensation to the holders of American National common stock;

•

the effect of the merger or any related transaction on, or the fairness of the consideration to be received by, holders of any class of securities of American National (other than the holders of American National common stock, solely with respect to the exchange ratio as described in KBW’s opinion and not relative to the consideration to be received by holders of any other class of securities) or holders of any class of securities of Atlantic Union or any other party to any transaction contemplated by the merger agreement;

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•

the actual value of Atlantic Union common stock to be issued in the merger;

•

the prices, trading range or volume at which American National common stock or Atlantic Union common stock would trade following the public announcement of the merger or the prices, trading range or volume at which Atlantic Union common stock would trade following the consummation of the merger;

•

any advice or opinions provided by any other advisor to any of the parties to the merger or any other transaction contemplated by the merger agreement; or

•

any legal, regulatory, accounting, tax or similar matters relating to American National, Atlantic Union, their respective shareholders, or relating to or arising out of or as a consequence of the merger or any related transactions (including the bank merger), including whether or not the merger would qualify as a tax-free reorganization for United States federal income tax purposes.

In performing its analyses, KBW made numerous assumptions with respect to industry performance, general business, economic, market and financial conditions and other matters, which are beyond the control of KBW, American National and Atlantic Union. Any estimates contained in the analyses performed by KBW are not necessarily indicative of actual values or future results, which may be significantly more or less favorable than suggested by these analyses. Additionally, estimates of the value of businesses or securities do not purport to be appraisals or to reflect the prices at which such businesses or securities might actually be sold. Accordingly, these analyses and estimates are inherently subject to substantial uncertainty. In addition, KBW’s opinion was among several factors taken into consideration by the American National board of directors in making its determination to approve the merger agreement and the merger. Consequently, the analyses described below should not be viewed as determinative of the decision of the American National board of directors with respect to the fairness of the exchange ratio. The type and amount of consideration payable in the merger were determined through negotiation between American National and Atlantic Union and the decision of American National to enter into the merger agreement was solely that of the American National board of directors.

The following is a summary of the material financial analyses presented by KBW to the American National board of directors in connection with its opinion. The summary is not a complete description of the financial analyses underlying the opinion or the presentation made by KBW to the American National board of directors, but summarizes the material analyses performed and presented in connection with such opinion. The financial analyses summarized below include information presented in tabular format. The tables alone do not constitute a complete description of the financial analyses. The preparation of a fairness opinion is a complex analytic process involving various determinations as to appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances. Therefore, a fairness opinion is not readily susceptible to partial analysis or summary description. In arriving at its opinion, KBW did not attribute any particular weight to any analysis or factor that it considered, but rather made qualitative judgments as to the significance and relevance of each analysis and factor. Accordingly, KBW believes that its analyses and the summary of its analyses must be considered as a whole and that selecting portions of its analyses and factors or focusing on the information presented below in tabular format, without considering all analyses and factors or the full narrative description of the financial analyses, including the methodologies and assumptions underlying the analyses, could create a misleading or incomplete view of the process underlying its analyses and opinion.

For purposes of the financial analyses described below, KBW utilized an implied transaction value for the merger of $40.55 per outstanding share of American National common stock, or approximately $430.9 million in the aggregate, based on the 1.35x exchange ratio provided for in the merger agreement and the closing price of Atlantic Union common stock on July 21, 2023. In addition to the financial analyses described below, KBW reviewed with the American National board of directors for informational purposes, among other things, implied transaction multiples for the merger (based on the implied transaction value for the merger of $40.55 per outstanding share of American National common stock) of 14.6x American National’s estimated calendar year 2023 earnings per share, or EPS, using publicly available consensus “street estimates” of American National.

Atlantic Union Selected Companies Analysis. Using publicly available information, KBW compared the financial performance, financial condition and market performance of Atlantic Union to nine selected

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major exchange-traded banks headquartered in Washington, D.C., Florida, Georgia, Maryland, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia with total assets between $10 billion and $30 billion. Live Oak Bancshares, Inc. was excluded from the selected companies.

The selected companies were as follows (shown in descending order of total assets):

Ameris Bancorp
United Community Banks, Inc.
WesBanco, Inc.
TowneBank
Seacoast Banking Corporation of Florida
Sandy Spring Bancorp, Inc.
FB Financial Corporation
First Bancorp
Eagle Bancorp, Inc.

To perform this analysis, KBW used profitability and other financial information for the latest 12 months, or LTM, or the most recent completed fiscal quarter, or MRQ, publicly available (which, in all cases, were the periods ended March 31, 2023) or as of the end of such periods and market price information as of July 21, 2023. KBW also used 2023 and 2024 EPS estimates taken from publicly available consensus “street estimates” for Atlantic Union and the selected companies. Certain financial data presented in the tables below may not correspond to the data presented in Atlantic Union’s historical financial statements as a result of the different periods, assumptions and methods used to compute the financial data presented below.

KBW’s analysis showed the following concerning the financial performance of Atlantic Union and the selected companies:

			Selected Companies
	Atlantic Union		75th Percentile		Average		Median		25th Percentile
LTM Core Return on Average Assets(1)		1.19%		1.28%		1.24%		1.21%		1.19%
LTM Core Return on Average Tangible Common Equity(1)		17.6%		16.9%		15.4%		15.3%		13.4%
LTM Core Pre-Tax Pre-Provision Return on Average Assets(2)		1.63%		1.93%		1.83%		1.77%		1.66%
LTM Net Interest Margin		3.47%		3.68%		3.47%		3.31%		3.30%
LTM Fee Income / Revenue Ratio		14.4%		19.1%		17.2%		15.5%		13.9%
LTM Efficiency Ratio		55.2%		49.0%		52.8%		51.4%		57.6%

(1)

Core net income excluded extraordinary items, non-recurring items and gains / (losses) on sale of securities, non-controlling interest and amortization of intangible and goodwill impairment.

(2)

Core net income excluding provision for loan losses and taxes.

KBW’s analysis also showed the following concerning the financial condition of Atlantic Union and the selected companies:

			Selected Companies
	Atlantic Union		75th Percentile		Average		Median		25th Percentile
Tangible Common Equity / Tangible Assets		6.91%		8.68%		8.36%		8.40%		8.09%
CET1 Ratio		9.91%		12.53%		11.76%		11.68%		11.11%
Total Capital Ratio		13.76%		14.74%		14.37%		14.55%		14.40%
Loans Held for Investment / Deposits		88.6%		100.5%		88.1%		83.8%		82.2%
Loan Loss Reserve / Loans		0.80%		1.36%		1.20%		1.09%		1.03%
Nonperforming Assets / Loans + OREO(1)		0.20%		0.40%		0.52%		0.42%		0.53%
LTM Net Charge-offs / Average Loans		0.05%		0.03%		0.05%		0.03%		0.06%

(1)

Nonperforming assets included nonaccrual loans, restructured loans and other real estate owned, or OREO.

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In addition, KBW’s analysis showed the following concerning the market performance of Atlantic Union and the selected companies:

			Selected Companies
	Atlantic Union		75th Percentile		Average		Median		25th Percentile
One-Year Stock Price Change		(13.7)%		(10.9)%		(20.2)%		(14.2)%		(23.9)%
Year-To-Date Stock Price Change		(19.4)%		(20.5)%		(29.8)%		(25.7)%		(26.7)%
Price / Tangible Book Value per Share		170%		160%		135%		136%		129%
Price / LTM EPS		10.5x		10.7x		10.1x		9.5x		8.5x
Price / 2023 EPS Estimate		11.3x		12.0x		10.8x		11.3x		9.5x
Price / 2024 EPS Estimate		11.1x		11.5x		10.7x		10.5x		9.2x
Dividend Yield(1)		4.0%		5.0%		3.8%		3.3%		2.6%
MRQ Dividend Payout Ratio(1)		68.7%		57.7%		49.8%		48.1%		29.8%

(1)

Most recent quarterly dividend annualized as a percentage of stock price in the case of dividend yield and annualized MRQ EPS in the case of dividend payout ratio.

No company used as a comparison in the above selected companies analysis is identical to Atlantic Union. Accordingly, an analysis of these results is not mathematical. Rather, it involves complex considerations and judgments concerning differences in financial and operating characteristics of the companies involved.

American National Selected Companies Analysis. Using publicly available information, KBW compared the financial performance, financial condition and market performance of American National to 21 selected major exchange-traded banks headquartered in Washington, D.C., Florida, Georgia, Maryland, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia with total assets between $2 billion and $5 billion.

The selected companies were as follows (shown in descending order of total assets):

SmartFinancial, Inc.
HomeTrust Bancshares, Inc.
Capital City Bank Group, Inc.
Carter Bankshares, Inc.
Primis Financial Corp.
Summit Financial Group, Inc.
Southern First Bancshares, Inc.
Burke & Herbert Financial Services Corp.
Shore Bancshares, Inc.
MVB Financial Corp.
MetroCity Bankshares, Inc.
Blue Ridge Bankshares, Inc.
CapStar Financial Holdings, Inc.
First Community Bankshares, Inc.
Colony Bankcorp, Inc.
C&F Financial Corporation
John Marshall Bancorp, Inc.
FVCBankcorp, Inc.
Capital Bancorp, Inc.
USCB Financial Holdings, Inc.
MainStreet Bancshares, Inc.

To perform this analysis, KBW used profitability and other financial information for the latest 12 months or the most recent completed fiscal quarter publicly available (which, in all cases, were the periods ended March 31, 2023) or as of the end of such periods and market price information as of July 21,

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2023. KBW also used 2023 and 2024 EPS estimates taken from publicly available consensus “street estimates” for American National and the selected companies to the extent publicly available (consensus “street estimates” were not publicly available for four of the selected companies). Where consolidated holding company level financial data for the selected companies was unreported, subsidiary bank level data was utilized to calculate ratios. Subsidiary bank level data necessary to calculate total capital ratio and CET1 ratio was also unreported for five of the selected companies. Certain financial data presented in the tables below may not correspond to the data presented in American National’s historical financial statements as a result of the different periods, assumptions and methods used to compute the financial data presented below.

KBW’s analysis showed the following concerning the financial performance of American National and the selected companies:

			Selected Companies
	American National		75th Percentile		Average		Median		25th Percentile
LTM Core Return on Average Assets(1)		1.13%		1.33%		1.15%		1.08%		1.00%
LTM Core Return on Average Tangible Common Equity(1)		15.0%		16.5%		13.6%		13.9%		11.0%
LTM Core Pre-Tax Pre-Provision Return on Average Assets(2)		1.52%		1.82%		1.70%		1.63%		1.39%
LTM Net Interest Margin		3.12%		4.14%		3.78%		3.50%		3.25%
LTM Fee Income / Revenue Ratio		15.9%		20.9%		16.2%		16.0%		12.1%
LTM Efficiency Ratio		57.0%		53.5%		59.7%		61.4%		67.2%

(1)

Core net income excluded extraordinary items, non-recurring items and gains / (losses) on sale of securities, non-controlling interest and amortization of intangible and goodwill impairment.

(2)

Core net income excluding provision for loan losses and taxes.

KBW’s analysis also showed the following concerning the financial condition of American National and, to the extent publicly available, the selected companies:

			Selected Companies
	American National		75th Percentile		Average		Median		25th Percentile
Tangible Common Equity / Tangible Assets		8.06%		9.21%		8.25%		8.13%		7.37%
CET1 Ratio		11.75%		12.97%		12.18%		11.67%		10.38%
Total Capital Ratio		13.93%		15.21%		14.48%		14.09%		13.46%
Loans Held For Investment / Deposits		84.2%		93.9%		87.6%		89.0%		83.0%
Loan Loss Reserve / Loans		1.13%		1.32%		1.29%		1.18%		1.03%
Nonperforming Assets / Loans + OREO(1)		0.09%		0.14%		0.49%		0.40%		0.60%
LTM Net Charge-offs / Average Loans		0.05%		(0.00)%		0.12%		0.02%		0.20%

(1)

Nonperforming assets included nonaccrual loans, restructured loans and OREO.

In addition, KBW’s analysis showed the following concerning the market performance of American National and, to the extent publicly available, the selected companies:

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			Selected Companies
	American National		75th Percentile		Average		Median		25th Percentile
One-Year Stock Price Change		(13.7)%		2.3%		(12.8)%		(14.3)%		(27.3)%
Year-To-Date Stock Price Change		(17.6)%		(4.5)%		(20.2)%		(24.4)%		(38.6)%
Price / Tangible Book Value per Share		137%		125%		113%		109%		97%
Price / LTM EPS		9.6x		11.1x		9.6x		9.3x		7.8x
Price / 2023 EPS Estimate		10.9x		11.2x		10.0x		9.8x		8.5x
Price / 2024 EPS Estimate		11.8x		10.2x		9.4x		9.3x		8.0x
Dividend Yield(1)		3.9%		3.8%		2.9%		3.2%		1.7%
MRQ Dividend Payout Ratio(1)		34.8%		37.8%		31.3%		24.3%		14.0%

(1)

Most recent quarterly dividend annualized as a percentage of stock price in the case of dividend yield and annualized MRQ EPS in the case of dividend payout ratio.

No company used as a comparison in the above selected companies analysis is identical to American National. Accordingly, an analysis of these results is not mathematical. Rather, it involves complex considerations and judgments concerning differences in financial and operating characteristics of the companies involved.

Selected Transactions Analysis. KBW reviewed publicly available information related to 19 selected U.S. whole bank transactions announced since December 31, 2020 with announced transaction values between $250 million and $750 million. The acquisition of Marlin Business Services Corp. by a non-bank buyer and one merger-of-equals transaction were excluded from the selected transactions.

The 19 selected transactions in this group were as follows:

Acquiror			Acquired Company
Washington Federal, Inc.			Luther Burbank Corporation
Prosperity Bancshares, Inc.			First Bancshares of Texas, Inc.
Seacoast Banking Corporation of Florida			Professional Holding Corp.
Brookline Bancorp, Inc.			PCSB Financial Corporation
United Community Banks, Inc.			Progress Financial Corporation
Origin Bancorp, Inc.			BT Holdings, Inc.
Simmons First National Corporation			Spirit of Texas Bancshares, Inc.
First Merchants Corporation			Level One Bancorp, Inc.
Old Second Bancorp, Inc.			West Suburban Bancorp, Inc.
South State Corporation			Atlantic Capital Bancshares, Inc.
United Community Banks, Inc.			Reliant Bancorp, Inc.
F.N.B. Corporation			Howard Bancorp, Inc.
Columbia Banking System, Inc.			Bank of Commerce Holdings
First Foundation Inc.			TGR Financial, Inc.
United Bankshares, Inc.			Community Bankers Trust Corporation
First Bancorp			Select Bancorp, Inc.
Enterprise Financial Services Corp			First Choice Bancorp
Eastern Bankshares, Inc.			Century Bancorp, Inc.
Peoples Bancorp Inc.			Premier Financial Bancorp, Inc.

For each selected transaction, KBW derived the following implied transaction statistics, in each case based on the transaction consideration value paid for the acquired company and using financial data based

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on the acquired company’s then latest publicly available financial statements prior to the announcement of the respective transaction or the acquiror’s public investor presentation for the respective transaction and, to the extent publicly available, one year forward estimated EPS prior to the announcement of the respective transaction:

•

transaction value per share to tangible book value per share of the acquired company;

•

pay to trade ratio (calculated using the transaction value to tangible book value multiple paid in the respective transaction as a percentage of the acquiror’s standalone closing stock price to tangible book value per share multiple);

•

price per common share to LTM core EPS (excluded extraordinary items, non-recurring items and gains / (losses) on sale of securities, non-controlling interest and amortization of intangibles and goodwill impairment) of the acquired company;

•

price per common share to estimated EPS of the acquired company for the first full year after the announcement of the respective transaction, which we refer to as NTM EPS, in the 17 selected transactions in which consensus “street estimates” for the acquired company were available at announcement; and

•

tangible equity premium to core deposits (total deposits less time deposits greater than $100,000) of the acquired company, referred to as core deposit premium.

KBW also reviewed the price per common share paid for the acquired company for the 16 selected transactions involving publicly traded acquired companies as a premium to the closing stock price of the acquired company one day prior to the announcement of the acquisition (expressed as a percentage and referred to as the one-day market premium). The resulting transaction statistics for the selected transactions were compared with the corresponding transaction statistics for the merger based on the implied transaction value for the merger of $40.55 per outstanding share of American National’s common stock, or $430.9 million in the aggregate, and using historical financial information for American National as of, or for the 12-month period ended, June 30, 2023 provided by American National, publicly available consensus “street estimates” for American National’s 2024 EPS, and the closing price of American National common stock on July 21, 2023.

The results of the analysis are set forth in the following table:

Atlantic
Union /
American
National

Selected Transactions

75th
Percentile

Average

Median

25th
Percentile

Price / Tangible Book Value per Share

179%

185%

164%

165%

156%

Pay to Trade Ratio

1.04x

1.03x

0.96x

0.95x

0.85x

Price / LTM Core EPS

12.5x

16.0x

15.1x

14.3x

12.4x

Price / NTM EPS

15.4x

15.2x

14.0x

14.1x

12.5x

Core Deposit Premium

7.8%

11.3%

8.0%

7.5%

6.2%

One-Day Market Premium

30.6%

30.2%

19.9%

15.0%

10.6%

No company or transaction used as a comparison in the above selected transaction analysis is identical to American National or the merger. Accordingly, an analysis of these results is not mathematical. Rather, it involves complex considerations and judgments concerning differences in financial and operating characteristics of the companies involved.

Relative Contribution Analysis. KBW analyzed the relative standalone contribution of Atlantic Union and American National to the combined market capitalization of the combined entity and various pro forma balance sheet and income statement items. This analysis did not include purchase accounting adjustments or cost savings. To perform this analysis, KBW used (i) balance sheet and net income data for Atlantic Union and American National as of, or for the 12-month period ended, June 30, 2023 provided by Atlantic Union and American National, respectively, (ii) publicly available consensus “street estimates” for Atlantic Union, (iii) financial and operating forecasts and projections of American National provided by

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American National management, and (iv) market price information as of July 21, 2023. The results of KBW’s analysis are set forth in the following table, which also compares the results of KBW’s analysis with the implied pro forma ownership percentages of Atlantic Union’s and American National’s respective shareholders in the combined company based on the 1.35x exchange ratio provided for in the merger agreement:

	Atlantic Union % of Total		American National % of Total
Ownership at 1.35x merger exchange ratio:		84%		16%
Market Information:
Pre-Transaction Market Capitalization		87%		13%
Balance Sheet:
Assets		87%		13%
Gross Loans Held for Investment		87%		13%
Deposits		86%		14%
Tangible Common Equity		84%		16%
Income Statement:
LTM Core Net Income(1)		87%		13%
2023 Estimated Earnings		85%		15%
2024 Estimated Earnings		87%		13%

(1)

Core net income excluded extraordinary items, non-recurring items and gains / (losses) on sale of securities, non-controlling interest and amortization of intangibles and goodwill impairment.

Financial Impact Analysis. KBW performed a pro forma financial impact analysis that combined projected income statement and balance sheet information of Atlantic Union and American National. Using (i) closing balance sheet estimates assumed as of December 31, 2023 for Atlantic Union and American National extrapolated from publicly available consensus “street estimates” of Atlantic Union and American National, (ii) calendar year 2024 EPS estimates for Atlantic Union and American National taken from publicly available consensus “street estimates” of Atlantic Union and American National, (iii) assumed net income growth rates for Atlantic Union and American National with respect to calendar year 2025 provided by Atlantic Union management, and (iv) pro forma assumptions (including, without limitation, the cost savings expected to result or be derived from the merger and certain purchase accounting and other merger related adjustments and restructuring charges assumed with respect thereto) provided by Atlantic Union management, KBW analyzed the potential financial impact of the merger on certain projected financial results of Atlantic Union. This analysis indicated the merger could be accretive to each of Atlantic Union’s estimated 2024 EPS and estimated 2025 EPS and dilutive to Atlantic Union’s estimated tangible book value per share at closing assumed as of December 31, 2023. Furthermore, the analysis indicated that, pro forma for the merger, each of Atlantic Union’s tangible common equity to tangible assets ratio, tier 1 leverage ratio, CET1 ratio, tier 1 capital ratio and total risk-based capital ratio at closing assumed as of December 31, 2023 could be lower. For all of the above analysis, the actual results achieved by Atlantic Union following the merger may vary from the projected results, and the variations may be material.

Atlantic Union Dividend Discount Model Analysis. KBW performed a dividend discount model analysis of Atlantic Union to estimate a range for the implied equity value of Atlantic Union. In this analysis, KBW used publicly available consensus “street estimates” of Atlantic Union and assumed long-term growth rates for Atlantic Union provided by Atlantic Union management, and assumed discount rates ranging from 10.5% to 12.5%. The range of values was derived by adding (i) the present value of implied future excess capital available for dividends that Atlantic Union could generate over the period from March 31, 2023 through December 31, 2027 as a standalone company, and (ii) the present value of Atlantic Union’s implied terminal value at the end of such period. KBW assumed that Atlantic Union would maintain a CET1 ratio of 9.50% and would retain sufficient earnings to maintain that level. In calculating implied terminal values for Atlantic Union, KBW applied a range of 9.5x to 13.5x Atlantic Union’s estimated 2028 earnings.

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This dividend discount model analysis resulted in a range of implied values per share of Atlantic Union common stock of $25.40 to $34.86.

The dividend discount model analysis is a widely used valuation methodology, but the results of such methodology are highly dependent on the assumptions that must be made, including asset and earnings growth rates, terminal values and discount rates. The foregoing dividend discount model analysis did not purport to be indicative of the actual values or expected values of Atlantic Union or the pro forma combined entity.

American National’s Dividend Discount Model Analysis. KBW performed a dividend discount model analysis of American National to estimate a range for the implied equity value of American National. In this analysis, KBW used financial forecasts and projections relating to the assets and earnings of American National provided by American National management, and assumed discount rates ranging from 10.5% to 12.5%. The range of values was derived by adding (i) the present value of implied future excess capital available for dividends that American National could generate over the period from March 31, 2023 through December 31, 2027 as a standalone company, and (ii) the present value of American National’s implied terminal value at the end of such period. KBW assumed that American National would maintain a CET1 ratio of 9.50% and would retain sufficient earnings to maintain that level. In calculating implied terminal values for American National, KBW applied a range of 9.0x to 12.0x American National’s estimated 2028 earnings. This dividend discount model analysis resulted in a range of implied values per share of American National common stock of $27.66 to $34.76.

Miscellaneous. KBW acted as financial advisor to American National in connection with the merger and did not act as an advisor to or agent of any other person. As part of its investment banking business, KBW is continually engaged in the valuation of bank and bank holding company securities in connection with acquisitions, negotiated underwritings, secondary distributions of listed and unlisted securities, private placements and valuations for various other purposes. As specialists in the securities of banking companies, KBW has experience in, and knowledge of, the valuation of banking enterprises. KBW and its affiliates, in the ordinary course of its and their broker-dealer businesses (and further to existing sales and trading relationships between each of American National and Atlantic Union and a KBW broker-dealer affiliate), may from time to time purchase securities from, and sell securities to, American National and Atlantic Union. In addition, as a market maker in securities, KBW and its affiliates may from time to time have a long or short position in, and buy or sell, debt or equity securities of American National or Atlantic Union for its and their own respective accounts and for the accounts of its and their respective customers and clients.

Under the KBW engagement agreement, American National agreed to pay KBW a cash fee equal to 1.25% of the aggregate merger consideration, $500,000 of which became payable to KBW with the rendering of KBW’s opinion and the balance of which is contingent upon the closing of the merger. As of July 24, 2023, and based upon the closing price of Atlantic Union common stock on that date of $30.94, KBW’s fee is anticipated to be approximately $5.5 million in the aggregate. American National also agreed to reimburse KBW for reasonable out-of-pocket expenses and disbursements incurred in connection with its retention and to indemnify KBW against certain liabilities relating to or arising out of KBW’s engagement or KBW’s role in connection therewith. Other than in connection with the present engagement, in the two years preceding the date of its opinion, KBW did not provide investment banking or financial advisory services to American National. In the two years preceding the date of its opinion, KBW provided investment banking and financial advisory services to Atlantic Union and received compensation for such services. KBW acted as lead book-running manager in Atlantic Union’s December 2021 offering of subordinated unsecured notes. KBW may in the future provide investment banking and financial advisory services to American National or Atlantic Union and receive compensation for such services.

Certain Unaudited Prospective Financial Information

Atlantic Union and American National do not as a matter of course make public projections as to future performance, revenues, earnings or other financial results due to, among other reasons, the inherent

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uncertainty of the underlying assumptions and estimates. However, Atlantic Union and American National are including in this proxy statement/prospectus certain unaudited prospective financial information for (a) American National, on a standalone basis without giving effect to the merger; (b) Atlantic Union, on a standalone basis without giving effect to the merger; and (c) the combined company after giving effect to the merger, including, among other things, estimated cost savings resulting or derived from the merger, that were made available as described below. The inclusion of this information should not be regarded as an indication that any of Atlantic Union, American National, KBW or their respective representatives or any other recipient of this information considered, or now considers, it to be necessarily predictive of actual future results, or that it should be construed as financial guidance, and it should not be relied on as such.

This information was prepared solely for internal use and is subjective in many respects. While presented with numeric specificity, the unaudited prospective financial information reflects numerous estimates and assumptions with respect to business, economic, market, competition, regulatory and financial conditions and matters specific to Atlantic Union’s and American National’s respective business, all of which are difficult to predict and many of which are beyond Atlantic Union’s and American National’s control. The unaudited prospective financial information reflects both assumptions as to certain business decisions that are subject to change and, in many respects, subjective judgment, and therefore, is susceptible to multiple interpretations and periodic revisions based on actual experience and business developments. No assurance can be given that the unaudited prospective financial information and the underlying estimates and assumptions will be realized. In addition, since the unaudited prospective financial information covers multiple years, such information by its nature becomes subject to greater uncertainty with each successive year. Actual results may differ materially from those set forth below, and important factors that may affect actual results and cause the unaudited prospective financial information to be inaccurate include, but are not limited to, risks and uncertainties relating to Atlantic Union’s and American National’s business, industry performance, general business and economic conditions, customer requirements, competition and adverse changes in applicable laws, regulations or rules. For other factors that could cause actual results to differ, please see the sections entitled “Risk Factors” and “Cautionary Statement Regarding Forward-Looking Statements.”

The unaudited prospective financial information appearing below was not prepared with a view toward public disclosure, nor was it prepared with a view toward compliance with GAAP, the prevailing practices in the banking industry, published guidelines of the SEC or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. In addition, the unaudited prospective financial information requires significant estimates and assumptions that make it inherently less comparable to the similarly titled GAAP measures in Atlantic Union’s or American National’s historical GAAP financial statements. Neither Atlantic Union’s nor American National’s independent registered public accounting firm, nor any other independent accountants, have compiled, examined or performed any procedures with respect to the unaudited prospective financial information contained in this document, nor have they expressed any opinion or any other form of assurance on such information or its achievability, and assume no responsibility for, and disclaim any association with, the unaudited prospective financial information. The independent registered public accountant reports incorporated by reference in this proxy statement/prospectus relate to historical financial information of each of Atlantic Union and American National. They do not extend to the unaudited prospective financial information and should not be read to do so.

Furthermore, except as set forth below under the section entitled “— Pro Forma Assumptions — Estimated Cost Savings Resulting or Derived from the Merger,” the unaudited prospective financial information does not take into account any circumstances or events occurring after July 24, 2023. No assurance can be given that, had the unaudited prospective financial information been prepared as of the date of this proxy statement/prospectus, similar estimates and assumptions would be used. Neither Atlantic Union nor American National intends to, and expressly disclaims any obligation to, make publicly available any update or other revision to the unaudited prospective financial information to reflect circumstances existing since their preparation or to reflect the occurrence of unanticipated events, even if any or all of the underlying assumptions are shown to be in error, or to reflect changes in general economic or industry conditions. Except as set forth below under the section entitled “— Pro Forma Assumptions — Estimated Cost Savings Resulting or Derived from the Merger,” the unaudited prospective financial information does not take into account the possible financial and other effects on Atlantic Union or American National

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of the merger and does not attempt to predict or suggest future results of the combined company after giving effect to the merger. Except as set forth below under the section entitled “— Pro Forma Assumptions — Estimated Cost Savings Resulting or Derived from the Merger,” the unaudited prospective financial information does not give effect to the merger, including the impact of negotiating or executing the merger agreement, the expenses that may be incurred in connection with completing the merger, the potential synergies that may be achieved by the combined company as a result of the merger, the effect on Atlantic Union or American National of any business or strategic decision or action that has been or will be taken as a result of the merger agreement having been executed, or the effect of any business or strategic decisions or actions that would likely have been taken if the merger agreement had not been executed, but that were instead altered, accelerated, postponed or not taken in anticipation of the merger. Further, the unaudited prospective financial information does not take into account the effect on Atlantic Union or American National of any possible failure of the merger to occur. By inclusion of the unaudited prospective financial information in this document, none of Atlantic Union, American National, KBW or their respective affiliates, associates, officers, directors, advisors, agents or other representatives makes any representation to any shareholder of Atlantic Union or American National or any other person regarding Atlantic Union’s or American National’s ultimate performance compared to the information contained in the unaudited prospective financial information or that the projected results will be achieved. The inclusion of the unaudited prospective financial information in this document should not be deemed an admission or representation by Atlantic Union or American National that it is viewed as material information, particularly in light of the inherent risks and uncertainties associated with such forecasts. The summary of the unaudited prospective financial information included below is not being included to influence your decision whether to vote to approve the merger, but is being provided solely because it was made available to KBW as discussed below, in connection with the merger.

In light of the foregoing, and considering that the American National special meeting will be held several months after the unaudited prospective financial information was prepared, as well as the uncertainties inherent in any forecasted information, shareholders are cautioned not to place unwarranted reliance on such information, and Atlantic Union and American National urge all shareholders to review Atlantic Union’s and American National’s financial statements and other information contained elsewhere in this document for a description of Atlantic Union’s and American National’s respective businesses and reported financial results. See the section entitled “Where You Can Find More Information.”

Certain Unaudited Prospective Financial Information of American National

For purposes of certain financial analyses performed in connection with KBW’s opinion, American National provided KBW with certain estimated unaudited prospective financial information for American National in 2023 and 2024, as well as estimated annual growth rates to be used to extrapolate American National’s financial results. The following table presents American National’s estimated unaudited prospective net income for the years ending December 31, 2023 and 2024, as provided to KBW by American National and used by KBW in performing financial analyses in connection with its opinion delivered to the American National board of directors.

			For the year ending December 31, 2023						For the year ending December 31, 2024
Net Income (in millions)				$	30.9					$	29.7

For purposes of the dividend discount model analysis for American National performed by KBW in connection with KBW’s opinion, American National management provided KBW with estimated annual growth rates of 5.0% in 2025 and thereafter for American National’s net income and 2.5% in 2023 and thereafter for American National’s risk weighted assets.

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The following table presents consensus Wall Street research estimates for American National’s 2023 and 2024 earnings per share and net income that were used by KBW in performing certain financial analyses in connection with its opinion delivered to the American National board of directors.

	For the year ending December 31, 2023			For the year ending December 31, 2024
EPS		$	2.77		$	2.64
Net Income (in millions)		$	29.5		$	28.0

In addition, for purposes of the financial impact analysis performed by KBW in connection with KBW’s opinion, Atlantic Union management provided KBW with an estimated annual growth rate of 6.0% in 2025 for American National’s net income.

Certain Unaudited Prospective Financial Information of Atlantic Union

The following table presents consensus Wall Street research estimates for Atlantic Union’s 2023 and 2024 earnings per share and net income that were used by KBW in performing financial analyses in connection with its opinion delivered to the American National board of directors.

	For the year ending December 31, 2023			For the year ending December 31, 2024
EPS		$	2.66		$	2.71
Net Income (in millions)		$	180.0		$	203.2

For purposes of the dividend discount model analysis of Atlantic Union performed by KBW in connection with KBW’s opinion delivered to the American National board of directors, Atlantic Union management provided KBW with estimated annual growth rates of 6.0% in 2025 and thereafter for Atlantic Union’s net income and 2.5% in 2023 and thereafter for Atlantic Union’s risk weighted assets.

Pro Forma Assumptions — Estimated Cost Savings Resulting or Derived from the Merger

For purposes of the financial impact analysis performed by KBW in connection with KBW’s opinion, Atlantic Union management provided KBW with assumed pro forma cost savings of 40.0% of American National’s projected 2024 noninterest expense of $68.0 million, phased in 75% in 2024.

See above in this section for further information regarding the uncertainties underlying the prospective financial information, including the estimated cost savings resulting or derived from the merger, as well as the sections entitled “Cautionary Statement Regarding Forward-Looking Statements” and “Risk Factors,” for further information regarding the uncertainties and factors associated with realizing cost savings in connection with the merger.

Atlantic Union’s Reasons for the Merger

In reaching its decision to adopt the merger agreement and approve the transactions contemplated thereby, including the merger, the Atlantic Union board of directors evaluated the merger agreement and the mergers in consultation with Atlantic Union’s management, as well as Atlantic Union’s financial and legal advisors, and considered a number of factors, including, among others, the following material factors, which are not presented in order of importance:

•

the fact that the mergers are expected to increase Atlantic Union’s scale, density and scarcity value in Virginia, particularly in southwest and southside Virginia, and enhances Atlantic Union’s presence in North Carolina, including in the attractive North Carolina Piedmont Triad region;

•

each of Atlantic Union’s, American National’s and the combined company’s business, operations, financial condition, asset quality, earnings and prospects;

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•

the fact that American National’s business and operations complement those of Atlantic Union and that the merger would result in a combined company with a diversified revenue stream from diversified geographic markets, a well-balanced portfolio and an attractive funding base;

•

the potential to broaden the scale of Atlantic Union’s organization and the expanded possibilities, including organic growth and future acquisitions, that would be available to the combined company, given its larger size, asset base, capital, and footprint;

•

its existing knowledge of American National’s business through the companies’ long-standing relationship and its review and discussions with Atlantic Union’s management concerning the additional due diligence examination of American National conducted in connection with the merger;

•

the complementary nature of the cultures of the two companies, including in their lending strategies and community focus, among other things which Atlantic Union’s management believes should facilitate integration and implementation of the mergers;

•

the complementary branch networks of Atlantic Union and American National;

•

the anticipated pro forma impact of the merger on the combined company, including the expected positive impact on certain financial metrics, such as earnings, return on assets, return on tangible common equity, and efficiency ratio;

•

its understanding of the current and prospective environment in which Atlantic Union and American National operate, including national, regional and local economic conditions, the competitive environment for financial institutions generally and the likely effect of these factors on Atlantic Union both with and without the mergers;

•

the market for alternative merger or acquisition transactions in the financial services industry and the likelihood and timing of other material strategic transactions;

•

the terms of the merger agreement, including the fixed exchange ratio, expected tax treatment, deal protection and termination fee provisions, which the Atlantic Union board of directors reviewed with Atlantic Union’s management and Atlantic Union’s outside financial and legal advisors;

•

the expectation of annual cost savings resulting from the transaction, which are expected to enhance efficiencies of the combined company;

•

the strong capital positions maintained by Atlantic Union and American National before the mergers and the anticipated strong capital position for the combined company following the mergers;

•

its belief that the mergers will permit the combined company to improve offerings to existing clients of both American National and Atlantic Union and expand its products and lending capacity;

•

Atlantic Union’s successful operating and acquisition track record, specifically Atlantic Union’s history of efficiently closing and integrating acquisitions;

•

its belief that the mergers are likely to provide substantial value to Atlantic Union shareholders;

•

the potential risks associated with achieving anticipated cost synergies and savings and successfully integrating American National’s business, operations and workforce with those of Atlantic Union;

•

the potential risk of diverting management attention and resources from the operation of Atlantic Union’s business and towards the completion of the mergers;

•

certain anticipated merger-related costs;

•

the regulatory and other approvals required in connection with the mergers and the current expectation that such regulatory approvals will be received in a timely manner and without the imposition of unacceptable conditions, including a burdensome condition;

•

the potential risk of losing other acquisition opportunities while Atlantic Union remains focused on completing the mergers; and

•

the nature and amount of payments and other benefits to be received by American National management in connection with the mergers.

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The foregoing discussion of the factors considered by the Atlantic Union board of directors is not intended to be exhaustive, but, rather, includes the material factors considered by the Atlantic Union board of directors. In reaching its decision to adopt the merger agreement and approve the mergers and the other transactions contemplated by the merger agreement, the Atlantic Union board of directors did not quantify or assign any relative weights to the factors considered, and individual directors may have given different weights to different factors. The Atlantic Union board of directors considered all these factors as a whole, and overall considered the factors to be favorable to, and to support, its determination to adopt the merger agreement and approve the transactions contemplated thereby, including the merger.

This explanation of the Atlantic Union board of directors’ reasoning and all other information presented in this section is forward-looking in nature and, therefore, should be read in light of the factors discussed in the section entitled “Cautionary Statement Regarding Forward-Looking Statements.”

Governance of Atlantic Union Following the Completion of the Merger

Under the merger agreement, at the effective time, Nancy Howell Agee and Joel R. Shepherd will join the boards of directors of each of Atlantic Union and Atlantic Union Bank, and as a result such boards will each consist of 13 members. Nancy Howell Agee and Joel R. Shepherd are currently members of the American National board of directors. Information about the current members of the Atlantic Union board of directors can be found in the documents listed under “Where You Can Find More Information” included elsewhere in this proxy statement/prospectus.

Interests of American National’s Directors and Executive Officers in the Merger

In considering the recommendations of the American National board of directors, American National shareholders should be aware that American National’s directors and executive officers have interests in the mergers that may be different from, or in addition to, the interests of the American National shareholders generally. These interests are described below. The American National board of directors was aware of these interests and considered them, among other matters, in adopting the merger agreement and approving the transactions contemplated by the merger agreement and in determining to recommend to the American National shareholders that they vote in favor of the merger proposal.

Treatment of American National Restricted Stock Awards

As of the date hereof, American National’s executive officers owned, in the aggregate, 41,474 shares of American National common stock underlying unvested American National restricted stock awards, including the following held by American National’s executive officers: Jeffrey V. Haley, 15,797; Jeffrey W. Farrar, 7,283; Edward C. Martin, 6,687; Rhonda P. Joyce, 6,388; and Alexander Jung, 5,319. Under the merger agreement, at the effective time, each American National restricted stock award that is unvested will fully vest and be cancelled and converted automatically into the right to receive the merger consideration in respect of each share of American National common stock underlying such award. None of American National’s non-employee directors holds unvested American National restricted stock awards.

For an estimate of the value to be received by each of American National’s named executive officers in respect of their unvested American National restricted stock awards outstanding as of the date hereof, see the section entitled “— Potential Payments and Benefits to American National Named Executive Officers in Connection with a Change in Control” below.

Employment Agreements with American National

Each of the executive officers of American National currently have operative employment agreements with American National.

American National will terminate the employment of Mr. Haley as of the effective time. American National expects to enter into a separation agreement with Mr. Haley on or before the effective time which will provide that Mr. Haley will be entitled to the change in control severance benefits described in his employment agreement, as described below, as well as the title to the Company-provided automobile that was made available to Mr. Haley immediately prior to the effective time.

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Under the terms of Mr. Haley’s employment agreement, if a “change in control” occurs and Mr. Haley’s employment is terminated by him for “good reason” or by American National due to its failure to renew such agreement or without “cause” (as those terms are defined in Mr. Haley’s employment agreement), in each case within 24 months following the change in control, Mr. Haley will be entitled to receive, subject to his execution and non-revocation of a general release of claims, a lump sum payment equal to the sum of: (i) any earned but unpaid incentive or bonus compensation with respect to any completed calendar year; (ii) a pro-rated cash bonus amount based on his prior year’s cash bonus amount; (iii) any other benefits or awards which, under the terms of any plans, policies or programs of American National, have been earned or become payable but which have not been paid; and (iv) an amount equal to either (a) 2.99 times Mr. Haley’s “total annual compensation” (as such term is defined in his employment agreement) or (b) if his employment terminates between his 65th birthday and the date he attains his U.S. Social Security Administration normal retirement age, the product of (1) his total annual compensation divided by 12 times (2) the number of months remaining between the date of termination and the date he attains his Social Security normal retirement age.

Atlantic Union expects to enter into retention agreements with each of Mr. Martin and Ms. Joyce, as described below under the section entitled, “— Employment with Atlantic Union Bank After the Merger.” In addition, Mr. Farrar and Mr. Jung are expected to enter into separation agreements in connection with the mergers. Such separation agreements are expected to provide that each executive officer will be entitled to the change in control severance benefits contained in their employment agreements and as described below; provided that each executes, and does not revoke, a general release of claims. The termination and change in control provisions of the employment agreements between American National and each of Mr. Martin, Ms. Joyce, Mr. Farrar and Mr. Jung are substantially the same as the corresponding provisions of Mr. Haley’s employment agreement, except the amount described in item (iv) in the preceding paragraph would be an amount equal to the product of (i) the executive officer’s total annual compensation divided by 12 times (ii) the lesser of 24 or the number of months remaining between the date of termination and the date the officer attains his or her Social Security normal retirement age.

Each employment agreement described above also provides that the severance payments and benefits to which the executive officer may be entitled in connection with a change in control will be reduced to the amount that does not trigger the excise tax under Section 4999 of the Code. No reduction, however, will be made, and the executive officer will be responsible for all excise and other taxes, if his or her after-tax position with no cutback exceeds his or her after-tax position with a cutback by more than five percent, which we refer to as the net best provision.

See the section entitled “Potential Payments and Benefits to American National Named Executive Officers in Connection with a Change in Control” below for an estimate of the value of the severance and benefits payments to American National’s named executive officers upon a qualifying termination under their employment agreements with American National.

2023 Annual Incentive Awards

American National’s named executive officers participate in American National’s 2023 performance compensation and bonus program under which they have the opportunity to earn incentive payments for 2023 performance. American National expects to pay annual bonuses under the 2023 performance compensation and bonus program based on actual performance following the end of the year consistent with its historical practice and the terms of such program; however, because the mergers may be completed before such planned payout, American National may decide to pay these annual incentive awards in cash earlier than historical practice and/or before the effective time, subject to Atlantic Union’s prior consent under the merger agreement. For quantification of the target amount that would be received by each of American National’s named executive officers, see the section entitled “— Potential Payments and Benefits to American National Named Executive Officers in Connection with a Change in Control” below.

Deferred Compensation Plans

As shown in the table in the section entitled, “— Potential Payments and Benefits to American National Named Executive Officers in Connection with a Change in Control,” certain deferred compensation amounts may be accelerated under the terms of the respective deferred compensation plan as a result of a

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change in control or a termination of employment under specified circumstances within 12 months of a change in control. In addition, under American National’s Non-Employee Director Deferral Plan, all amounts credited to a participant’s account will become immediately due and payable as of the date of a change in control.

Agreements between Mr. Haley and Atlantic Union Bank

Atlantic Union Bank has entered into a consulting agreement with Mr. Haley, effective immediately following the effective time and subject to Mr. Haley’s execution of the separation agreement with American National as described above. Mr. Haley’s consulting agreement provides that he will serve as a special advisor to Atlantic Union Bank for a two-year period beginning immediately following the effective time. Atlantic Union Bank may terminate the consulting agreement only for “cause” (as such term is defined in the consulting agreement). Mr. Haley will be entitled to a cash payment of $2,000,000, which will be paid in a lump sum within 15 business days following the effective time (subject to Mr. Haley’s obligations to repay a prorated portion of such payment if the consulting agreement is terminated under certain circumstances). In addition, Mr. Haley will be subject to enhanced non-competition and non-solicitation covenants that will apply across Atlantic Union’s footprint for two years following the effective time.

Atlantic Union Bank also has entered into a charitable trust services agreement with Mr. Haley, effective immediately following the effective time. Under the charitable trust services agreement, Mr. Haley will serve as Atlantic Union Bank’s representative to two charitable trusts for which Atlantic Union Bank, as successor to American National and Trust Company, will serve as trustee: the Alexander Berkeley & Ruth S. Carrington, Jr. Charitable Trust and the E Stuart James Grant Charitable Trust. The funds of these trusts are distributed periodically to various community and charitable organizations to benefit Danville, Virginia and surrounding communities. The term of the charitable trust services agreement is 20 years, during which Mr. Haley will perform the services expected of a trustee representative of a charitable trust. In consideration for these services and subject to Mr. Haley’s continued engagement, Mr. Haley will receive an annual cash payment of $50,000 per trust. Atlantic Union Bank may terminate the charitable trust services agreement only for “cause” (as such term is defined in the charitable trust services agreement).

Employment with Atlantic Union Bank After the Merger

In connection with the merger, Atlantic Union Bank expects to enter into retention agreements with each of Mr. Martin and Ms. Joyce which will constitute offers of employment, to be effective upon completion of the merger. In addition, in exchange for waiving any rights they may have under their employment agreement with American National and executing, without revocation, a general release of claims, the retention agreements will provide for a payment which will generally be equal to the amount of the change in control severance each of Mr. Martin and Ms. Joyce would have received under their respective employment agreements with American National if their employment had been terminated following the effective time as described above. The retention agreements are also expected to provide for base salary, annual bonus and equity incentives, a retention equity award, participation in executive benefit plans, and coverage under Atlantic Union Bank’s executive severance plan.

Indemnification and Insurance of Directors and Officers

The merger agreement provides that Atlantic Union will maintain American National’s existing directors’ and officers’ liability insurance, except Atlantic Union or the surviving corporation is not obligated to expend more than 300%, on an annual basis, of the current annual premium paid by American National for its current policy. In lieu of the insurance policy described in the preceding sentence, Atlantic Union or American National, in consultation with the other party, may obtain at or before the effective time a six-year “tail” policy under American National’s existing directors’ and officers’ insurance policy providing equivalent coverage to that described in the preceding sentence.

Atlantic Union, as the surviving corporation, will indemnify any person who is entitled to indemnification from American National or any of its subsidiaries for matters existing or occurring at or before the effective time, including matters, acts or omissions occurring in connection with the approval of the merger agreement and the transactions contemplated by the merger agreement; provided, that the indemnified

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party to whom expenses are advanced agrees to repay such advances if it is ultimately determined that such indemnified party is not entitled to indemnification.

Combined Company’s Board of Directors

Under the merger agreement, at the effective time, Nancy Howell Agee and Joel R. Shepherd will join the boards of directors of each of Atlantic Union and Atlantic Union Bank.

Potential Payments and Benefits to American National’s Named Executive Officers in Connection with a Change in Control

The information set forth in the following table is intended to comply with Item 402(t) of the SEC’s Regulation S-K, which requires disclosure of information about the payments and benefits that may be paid or become payable to American National’s named executive officers that is based on or otherwise relates to the merger. Such compensation is the subject of the compensation proposal.

For purposes of this compensation-related disclosure, all of American National’s executive officers are named executive officers.

The amounts shown below are estimates based on multiple assumptions that may or may not actually occur or be accurate on the relevant date, including the assumptions described below, and do not reflect certain compensation actions that may be taken or that may occur before completion of the merger. As a result, the actual amounts, if any, to be received by a named executive officer of American National may differ materially from the amounts shown below. Except as otherwise specifically noted, for purposes of quantifying the potential payments and benefits described in this section, the following assumptions were used:

•

the relevant price per share of American National common stock is $40.07, which is the average closing price per share of American National common stock as quoted on Nasdaq over the first five business days following the first public announcement of the merger on July 25, 2023;

•

the effective time takes place on August 1, 2023, which is the assumed date of the closing solely for purposes of the disclosure in this section;

•

the employment of each executive officer of American National is terminated “without cause” (as such term is defined in the relevant American National employment agreements in effect on that date) immediately following the assumed effective time on August 1, 2023, or the executive officer is subject to a retention or separation agreement as described above providing for a payment equal to the amount of the change in control severance under such executive officer’s employment agreement with American National; and

•

each named executive officer receives an annual bonus under American National’s 2023 performance compensation and bonus program equal to such executive officer’s target incentive payment.

The amounts below do not include the value of benefits in which the named executive officers are vested without regard to the occurrence of a change in control. The amounts below also do not reflect the potential reductions in payments and benefits after the application of the net best provision described above.

Name	Cash ($)(1)		Equity ($)(2)		Pension / NQDC ($)(3)		Perquisites / Benefits ($)		Total ($)(5)
Jeffrey V. Haley		4,105,535		632,986		—		100,000(4)		4,838,521
Jeffrey W. Farrar		1,586,499		291,830		47,776		—		1,878,329
Edward C. Martin		1,469,460		267,948		—		—		1,737,408
Rhonda P. Joyce		1,427,482		255,967		350,000		—		2,033,449
Alexander Jung		1,296,879		213,132		—		—		1,510,011

(1)

Cash. The amounts in this column reflect (i) cash severance payments to which the named executive officer would be entitled to receive in connection with the merger either under the executive’s employment agreement as described under “— Employment Agreements with American National,” or as payment in lieu thereof under Ms. Joyce’s and Mr. Martin’s retention agreements or

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under Mr. Haley’s, Mr. Farrar’s and Mr. Jung’s separation agreements, as applicable, and based on the assumptions set forth above and (ii) target annual bonus amounts under American National’s 2023 performance compensation and bonus program (detailed below). The payments in lieu of severance are equivalent to those that otherwise would be made under such executive’s employment agreement. The cash severance payable under an executive’s employment agreement or in lieu thereof under a separation agreement, as applicable, is considered a “double trigger” benefit since the severance amounts are conditioned upon a termination of employment without cause or resignation with good reason following a change in control of American National. The amounts paid in lieu of such severance under an executive’s retention agreement are single trigger payments because they are payable in connection with a change in control without regard to termination of employment. Payment of the 2023 annual bonuses are “single trigger” payments because they are payable in connection with a change in control without regard to termination of employment.

Name	Payments in Lieu of Severance ($)		Annual Bonus ($)		Total Cash ($)
Jeffrey V. Haley		3,745,535		360,000		4,105,535
Jeffrey W. Farrar		1,395,394		191,105		1,586,499
Edward C. Martin		1,294,560		174,900		1,469,460
Rhonda P. Joyce		1,256,857		170,625		1,427,482
Alexander Jung		1,142,379		154,500		1,296,879

(2)

Equity. The amounts in this column reflect the value of unvested American National restricted stock awards that will vest at the effective time as described under “— Treatment of American National Restricted Stock Awards” by multiplying such amounts by $40.07, which is the average closing price per share of American National common stock as quoted on Nasdaq over the first five business days following the first public announcement of the merger on July 25, 2023. The amounts do not include the actual value the named executive officers will receive under the terms of the merger agreement. The values shown are different from — and significantly higher than — the valuation of the accelerated vesting of outstanding American National restricted stock awards for purposes of Section 280G of the Code. The amounts payable under this column are considered a “single trigger” benefit since they are payable upon completion of the merger without regard to termination of employment.

(3)

Pension / NQDC. For Mr. Farrar, the amount in this column reflects 25% of the annual bonus under American National’s 2023 performance compensation and bonus program that Mr. Farrar elected to defer under the VBA Deferred Compensation Plan for American National Bank and Trust Company and which would be payable upon a change in control. The full bonus amount is already reflected in the cash column, and the portion subject to the election is also being shown in this column to reflect the acceleration of this amount. For Ms. Joyce, the amount in this column is the estimated maximum value that would be payable in an immediate lump sum rather than in the form of an annuity commencing at normal retirement age under her Mid-Carolina Bank Restated Salary Continuation Agreement, if her employment ended due to a good reason or involuntary termination without cause within 12 months of a change in control.

(4)

This amount reflects the estimated value of the Company-provided automobile transferred to Mr. Haley in connection with his separation agreement as described above.

(5)

Total. Except with respect to Mr. Farrar, the amounts in this column reflect the total payments across all previous columns. For Mr. Farrar, the total reflects solely the sum of the cash column and the equity column, because the cash column includes the full target annual bonus, which amount is inclusive of the portion of his annual bonus that would be deferred and become payable upon a change in control under the VBA Deferred Compensation Plan for American National Bank and Trust Company, as reflected in the pension/NQDC column.

Regulatory Approvals Required for the Mergers

Subject to the terms of the merger agreement, both Atlantic Union and American National have agreed to cooperate with each other and use their reasonable best efforts to promptly prepare and file all documentation, to effect all applications, notices, petitions and filings, and to obtain all permits, consents, orders, approvals, waivers, non-objections and authorizations of all third parties and governmental entities that are necessary or advisable to complete the transactions contemplated by the merger agreement, including the mergers. Atlantic Union and American National have filed all necessary applications and notifications to obtain the required regulatory approvals, consents and waivers.

The merger requires the approval of the Federal Reserve under the Bank Holding Company Act of 1956, as amended, and the approval of the VBFI under the Code of Virginia. The bank merger requires the approval of the Federal Reserve under the Bank Merger Act, and the approval of the VBFI under the

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Code of Virginia. In addition, the termination of American National Bank and Trust Company as a separate legal entity requires notice to the Office of the Comptroller of the Currency under federal regulations.

Although neither Atlantic Union nor American National knows of any reason why the parties cannot obtain regulatory approvals required to complete the mergers in a timely manner, Atlantic Union and American National cannot be certain of when or if such approvals will be obtained.

The United States Department of Justice, which we refer to as the DOJ, has between 15 and 30 days following approval of the merger or the bank merger by the Federal Reserve to challenge the approval on antitrust grounds. While Atlantic Union and American National do not know of any basis on which the DOJ would challenge regulatory approval by the Federal Reserve and believe that the likelihood of such action is remote, there can be no assurance that the DOJ will not initiate such a proceeding, or if such a proceeding is initiated, as to the result of any such challenge.

Notifications and/or applications requesting approval may be submitted to various other federal and state regulatory authorities and self-regulatory organizations.

The approval of any notice or application merely implies satisfaction of regulatory criteria for approval, and does not include review of the mergers from the standpoint of the adequacy of the consideration to be received by, or fairness to, shareholders. Regulatory approval does not constitute an endorsement or recommendation of the mergers.

Atlantic Union and American National are not aware of any material governmental approvals or actions that are required before the completion of the mergers other than those described in this proxy statement/prospectus. If any additional governmental approvals or actions are required other than those described in this proxy statement/prospectus, Atlantic Union and American National presently intend to seek those approvals or actions. However, Atlantic Union and American National cannot assure you that any of these additional approvals or actions will be obtained.

Accounting Treatment of the Merger

Public Trading Markets

Appraisal Rights of American National Shareholders

Under Virginia law, American National shareholders will not be entitled to exercise any appraisal or dissenters’ rights in connection with the merger.

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THE MERGER AGREEMENT

The following describes certain material provisions of the merger agreement, but does not describe all of the terms of the merger agreement and may not contain all of the information about the merger agreement that is important to you. The following is not intended to provide factual information about the parties or any of their respective subsidiaries or affiliates. The following description of the merger agreement is subject to, and qualified in its entirety by reference to, the merger agreement, which is attached to this proxy statement/prospectus as Annex A and is incorporated by reference into this proxy statement/prospectus. We urge you to read the merger agreement carefully and in its entirety, as it is the legal document governing the mergers.

Explanatory Note Regarding the Merger Agreement

The merger agreement and this summary of terms are included to provide you with information regarding the terms of the merger agreement. Factual disclosures about Atlantic Union and American National contained in this proxy statement/prospectus or in the public reports of Atlantic Union or American National filed with the SEC may supplement, update or modify the factual disclosures about Atlantic Union and American National contained in the merger agreement. The representations, warranties and covenants made in the merger agreement by Atlantic Union and American National were made solely for the benefit of the parties to the merger agreement and are qualified and subject to important limitations agreed to by Atlantic Union and American National in connection with negotiating the terms of the merger agreement. In particular, in your review of the representations and warranties contained in the merger agreement and described in this summary, it is important to bear in mind that the representations and warranties were negotiated with the principal purpose of establishing circumstances in which a party to the merger agreement may have the right not to complete the merger if the representations and warranties of the other party prove to be untrue due to a change in circumstance or otherwise, and allocating risk between the parties to the merger agreement, rather than establishing matters as facts. The representations and warranties also may be subject to a contractual standard of materiality different from the standard generally applicable to shareholders and reports and documents filed with the SEC, and some were qualified by the matters contained in the confidential disclosure schedules that Atlantic Union and American National each delivered in connection with the merger agreement and certain documents filed with the SEC. Moreover, information concerning the subject matter of the representations and warranties, which do not purport to be accurate as of the date of this proxy statement/prospectus, may have changed since the date of the merger agreement. Accordingly, the representations and warranties in the merger agreement should not be relied on by any persons as characterizations of the actual state of facts about Atlantic Union and American National at the time they were made or otherwise.

Structure of the Mergers

Under the merger agreement, American National will merge with and into Atlantic Union with Atlantic Union continuing as the surviving corporation. Immediately following the merger, American National Bank and Trust Company will merge with and into Atlantic Union Bank with Atlantic Union Bank continuing as the surviving bank.

The Merger Consideration

At the effective time, each share of American National common stock, except for certain shares of American National common stock owned by American National or Atlantic Union, that is issued and outstanding immediately prior to the effective time, will be converted into the right to receive the merger consideration.

Fractional Shares

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Treatment of the Restricted Stock Awards

Surviving Corporation Governing Documents, Directors and Officers

At the effective time, the Atlantic Union articles and the Atlantic Union bylaws in effect immediately prior to the effective time will be the articles of incorporation and bylaws of Atlantic Union as the surviving corporation of the merger, until the same be amended or repealed in accordance with their respective terms and applicable law.

Closing and Effective Time

The mergers will be completed only if all conditions to the merger discussed in this proxy statement/prospectus and set forth in the merger agreement are either satisfied or waived. See the section entitled “— Conditions to Completion of the Merger” below.

The merger will become effective at the date and time specified in the articles of merger filed with the Virginia State Corporation Commission, or at such later time as provided by applicable law. The bank merger will become effective immediately following the merger.

Under the merger agreement, except as Atlantic Union and American National may otherwise mutually agree, the closing will occur on the first day of the calendar month immediately following the calendar month in which the last of the conditions specified in the merger agreement is satisfied or waived in writing, except that if such satisfaction or waiver occurs on or after the 20th day of a calendar month, then the closing will occur on the first day of the calendar month that is the second calendar month from the month in which such satisfaction or waiver occurs. The merger agreement also provides that the closing will not occur before January 1, 2024. We expect to complete the mergers in the first quarter of 2024. However, we cannot assure you of when or if the mergers will be completed.

As described below, if the merger has not closed by July 24, 2024, the merger agreement may be terminated by either Atlantic Union or American National, as long as the failure of the effective time to occur on or before that date is not caused by any breach of the merger agreement by the party electing to terminate the merger agreement.

Conversion of Shares; Exchange Procedures

The conversion of American National common stock into the right to receive the merger consideration will occur automatically at the effective time.

Exchange Agent

Before the effective time, Atlantic Union will appoint an exchange agent, which we refer to as the exchange agent, for the payment and exchange of the merger consideration, under an exchange agent agreement to be entered into between Atlantic Union and the exchange agent.

Exchange Procedures

At or before the effective time, Atlantic Union will deposit with the exchange agent cash sufficient to pay the cash payable in lieu of fractional shares of Atlantic Union common stock that would otherwise be issued in the merger and certificates representing, or at Atlantic Union’s option, evidence in book-entry form of, shares of Atlantic Union common stock to be paid under the merger agreement. Within five business

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days after the effective time, Atlantic Union will cause the exchange agent to mail to each holder of record of American National common stock immediately before the effective time transmittal materials, which such holder may complete in accordance with the instructions thereto and deliver together with the proper surrender of a certificate, if applicable, to the exchange agent in exchange for the merger consideration and any cash in lieu of fractional shares of American National common stock, and any dividends or distributions which such shareholder is entitled to receive under the merger agreement.

Withholding

Atlantic Union, the surviving corporation or the exchange agent, as applicable, will be entitled to deduct and withhold from any cash payable in lieu of fractional shares or any other amounts otherwise payable under the merger agreement to any American National shareholder or holder of an American National restricted stock award such amounts, if any, as it is required to deduct and withhold with respect to making of such payment under the Code or any provision of state, local or foreign tax law. To the extent that any amounts are so deducted or withheld, these amounts will be treated for all purposes of the merger agreement as having been paid to the person in respect of which such deduction and withholding was made.

Dividends and Distributions

Any dividend or other distribution declared by Atlantic Union on Atlantic Union common stock with a record date after the effective time will not be paid to any former record holder of American National common stock until such holder has surrendered its certificate, if any, representing American National common stock in accordance with the merger agreement. After the surrender of any such certificate, the record holder of the whole shares of Atlantic Union common stock issued in exchange therefor will be paid, without interest, the merger consideration together with any such undelivered dividends and other distributions.

Representations and Warranties

The merger agreement contains representations and warranties made, on the one hand, by American National to Atlantic Union and, on the other hand, by Atlantic Union to American National, which were made only for purposes of the merger agreement.

In the merger agreement, American National has made customary representations and warranties to Atlantic Union with respect to:

•

the due organization, valid existence, good standing and power and authority of American National, American National Bank and Trust Company, and American National’s other subsidiaries;

•

the capitalization of American National, including in particular the number of shares of American National common stock issued and outstanding;

•

ownership of subsidiaries;

•

American National’s authority to enter into the merger agreement and to complete the transactions contemplated by the merger agreement and the enforceability of the merger agreement against American National in accordance with its terms;

•

the absence of violations or breaches of American National’s governing instruments, certain agreements or applicable laws as a result of entering into the merger agreement and the completion of the transactions contemplated by the merger agreement;

•

the required applications, filings and notices with regulatory authorities in connection with the transactions contemplated by the merger agreement;

•

reports filed with regulatory authorities;

•

financial matters;

•

the absence of certain undisclosed liabilities;

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•

the absence of undisclosed brokers’ fees and expenses;

•

the absence since December 31, 2022 of an event that has had a material adverse effect on American National, and American National and its subsidiaries having conducted their respective businesses in all material respects only in the ordinary course since December 31, 2022;

•

legal proceedings;

•

tax matters and tax treatment of the merger;

•

labor and employment matters;

•

matters relating to employee benefit plans and ERISA;

•

compliance with laws, including the Community Reinvestment Act;

•

matters with respect to certain of American National’s contracts;

•

agreements with regulatory agencies;

•

derivative transactions entered into for the account of American National or its subsidiaries or its or their customers;

•

environmental matters;

•

investment securities;

•

real property;

•

intellectual property;

•

customer relationships with wealth management customers of American National;

•

transactions with affiliates and related parties;

•

the inapplicability of state anti-takeover statutes;

•

receipt by the American National board of directors of the opinion from American National’s financial advisor;

•

accuracy of the information relating to American National for inclusion in the filings with the SEC in connection with the completion of the transactions contemplated by the merger agreement;

•

loan portfolio;

•

deposits and deposit accounts;

•

insurance matters; and

•

neither American National nor any subsidiary being required to register with the SEC as an investment advisor or broker-dealer, or conducting insurance operations that require a license from a governmental entity.

In the merger agreement, Atlantic Union made customary representations and warranties to American National with respect to:

•

the due organization, valid existence, good standing and power and authority of Atlantic Union, Atlantic Union Bank and Atlantic Union’s other subsidiaries;

•

the capitalization of Atlantic Union, including in particular the number of shares of Atlantic Union common stock issued and outstanding;

•

ownership of subsidiaries;

•

Atlantic Union’s authority to enter into the merger agreement and to complete the transactions contemplated by the merger agreement and the enforceability of the merger agreement against Atlantic Union in accordance with its terms;

•

the absence of violations or breaches of Atlantic Union’s governing instruments, certain agreements or applicable laws as a result of entering into the merger agreement and the completion of the transactions contemplated by the merger agreement;

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•

the required applications, filings and notices with regulatory authorities in connection with the transactions contemplated by the merger agreement;

•

reports filed with regulatory authorities;

•

financial matters;

•

the absence of undisclosed brokers’ fees and expenses;

•

the absence since December 31, 2022 of an event that has had a material adverse effect on Atlantic Union, and Atlantic Union and its subsidiaries having conducted their respective businesses in all material respects only in the ordinary course since December 31, 2022;

•

legal proceedings;

•

tax matters and tax treatment of the merger;

•

compliance with laws, including the Community Reinvestment Act;

•

the inapplicability of state anti-takeover statutes;

•

accuracy of the information relating to Atlantic Union for inclusion in the filings with the SEC in connection with the completion of the transactions contemplated by the merger agreement; and

•

insurance matters.

The representations and warranties in the merger agreement do not survive the effective time and, as described below under the section entitled “— Effect of Termination,” if the merger agreement is validly terminated, the merger agreement will become void and have no effect (except with respect to designated provisions of the merger agreement, including, but not limited to, those related to payment of fees and expenses and the confidential treatment of information), unless a party committed fraud or willfully and materially breached the merger agreement.

Many of the representations and warranties in the merger agreement made by American National and Atlantic Union are qualified by a materiality or material adverse effect standard (that is, they will not be deemed to be untrue or incorrect unless their failure to be true or correct is material or would result in a material adverse effect).

Under the merger agreement, a “material adverse effect” is defined, with respect to a party, as any effect, change, event, fact, circumstance, condition, occurrence or development that, either individually or in the aggregate, has had or would reasonably be expected to have a material adverse effect on (i) the business, properties, assets, liabilities, results of operations or financial condition of such party and its subsidiaries taken as a whole or (ii) the ability of such party to timely complete the transactions contemplated by the merger agreement, except that in the case of the foregoing clause (i), a material adverse effect will not be deemed to include the impact of the following (except, in certain instances, to the extent that the effects of such change are materially disproportionately adverse to the business, properties, results of operations or financial condition of such party and its subsidiaries, taken as a whole, as compared to other companies in the industry in which such party and its subsidiaries operate):

•

changes after the date of the merger agreement in U.S. generally accepted accounting principles, which we refer to as GAAP, or applicable regulatory accounting requirements;

•

changes after the date of the merger agreement in laws, rules or regulation of general applicability to the financial services industry or the interpretation thereof by any governmental entity;

•

changes after the date of the merger agreement in global, national or regional political conditions or in economic or market conditions generally affecting the financial services industry generally;

•

the public disclosure of the transactions contemplated by the merger agreement or actions or omissions expressly required by the merger agreement or that are taken with the prior written consent of the other party in contemplation of the transactions contemplated by the merger agreement;

•

changes after the date of the merger agreement resulting from hurricanes, earthquakes, tornados, floods or other natural disasters or from any epidemic, pandemic, or outbreak of any disease or other public health event; and

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•

decline in the trading price of a party’s common stock or the failure, in and of itself, to meet earnings projections or internal financial forecasts, but in either case, not including any underlying causes thereof.

Covenants and Agreements

Conduct of Business Prior to the Effective Time

American National has agreed that until the effective time, unless Atlantic Union provides its prior written consent (which it may not unreasonably withhold, condition or delay) and except for certain exceptions and as otherwise expressly contemplated or permitted by the merger agreement or as required by law, American National will not, and will not permit any of its subsidiaries to do, any of the following:

•

conduct its business other than in the ordinary course or fail to use its reasonable best efforts to maintain and preserve intact its business organization, rights, permits, franchises, business relationships with customers, vendors, strategic partners, suppliers, distributors and others doing business with it, and the services of its officers and key employees;

•

incur, assume, guarantee, endorse or otherwise as an accommodation become responsible for any debt obligation or other indebtedness or obligation for borrowed money, other than certain debt incurred in the ordinary course;

•

adjust, split, combine or reclassify any of its capital stock;

•

make, declare, pay or set a record date for any dividend or any other distribution on, or directly or indirectly redeem, purchase or otherwise acquire, any shares of its capital stock or other equity or voting securities or any securities or obligations convertible or exchangeable into, or exercisable for, any shares of its capital stock or other equity or voting securities, other than certain ordinary course of dividends and distributions;

•

grant any stock options, restricted stock units, performance stock units, phantom stock units, restricted shares or other equity-based awards or interests, or grant any person any right to acquire any of its or its subsidiaries’ equity securities;

•

make any new loans to any of its or its subsidiaries’ “executive officers” or other “insiders” as defined in Regulation O promulgated by the Federal Reserve in excess of $500,000;

•

issue, sell, transfer, encumber or otherwise permit to become outstanding any shares of capital stock or voting securities or equity interests or securities convertible or exchangeable into, or exercisable for, any shares of its capital stock or other equity or voting securities, or any options, warrants, or other rights of any kind to acquire any shares of capital stock or other equity or voting securities, other than pursuant to (i) the vesting or settlement of equity-based awards outstanding as of the date of the merger agreement or (ii) American National’s dividend reinvestment plan;

•

adopt or implement any shareholder rights plan or similar arrangement;

•

(i) purchase any securities, other than investment securities in the ordinary course, or make any acquisition of or investment in any person other than American National Bank and Trust Company, or otherwise acquire direct or indirect control over any person, or (ii) enter into a plan of consolidation, merger, share exchange, share acquisition, reorganization, recapitalization or complete or partial liquidation or dissolution, or a letter of intent, memorandum of understanding or agreement in principle with respect thereto;

•

sell, transfer, mortgage, encumber or otherwise dispose of any of its material properties or assets, other than investment securities in the ordinary course, to any person other than a wholly owned subsidiary, or cancel, release or assign any indebtedness to any such person or any claims held by any such person;

•

other than transactions in the ordinary course, (i) terminate, materially amend, or waive any material provision of, or waive, release, compromise or assign any material rights or claims under, certain of its contracts, or make any change in any instrument or agreement governing the terms of any of its

TABLE OF CONTENTS

securities, or (ii) enter into any contract that would have been made available to Atlantic Union under the merger agreement if it were in effect on the date of the merger agreement;

•

except as required under any of its benefit plans existing on the date of the merger agreement, including for compliance with applicable law or as required by third-party benefit administrators, (i) enter into, adopt or terminate any employee benefit or compensation plan, program, policy or arrangement for the benefit or welfare of any current or former employee, officer, director or individual consultant, other than in connection with a new hire or a promotion, in each instance, in the ordinary course, (ii) amend any employee benefit or compensation plan, program, policy or arrangement for the benefit or welfare of any current or former employee, officer, director or individual consultant, (iii) increase the compensation or benefits payable to current or former employees, officers, directors or individual consultants by an amount greater than 3% of the total compensation and benefits payable to such individuals as of the date of the merger agreement, other than in connection with a promotion, (iv) pay or award, or accelerate the vesting of, any non-equity-based bonuses or incentive compensation, (v) waive any stock repurchase rights, or grant, accelerate, amend or change the period of exercisability of any equity-based awards or other equity-based compensation, or authorize cash payments in exchange for any equity-based awards or other equity-based compensation, (vi) enter into any new, or amend any existing, employment, severance, change in control, retention or bonus agreement or similar agreement or arrangement, other than in connection with a new hire or a promotion, (vii) fund any rabbi trust or similar arrangement, (viii) terminate the employment or services of any officer or any employee whose annual base salary or wage rate is greater than $200,000, other than for cause, (ix) hire any officer, employee or individual consultant who has an annual base salary or wage rate greater than $200,000 other than to replace a departed employee or fill an open position, or (x) become a party to or bound by any collective bargaining agreement or other agreement with a labor union or labor organization with respect to its employees;

•

(i) commence any claim, suit, action or proceeding other than in the ordinary course, or (ii) settle any claim, suit, action or proceed

	Annex A:			Agreement and Plan of Merger, dated as of July 24, 2023, by and between Atlantic Union Bankshares Corporation and American National Bankshares Inc.
	Annex B:			Form of Affiliate Agreement, by and among Atlantic Union Bankshares Corporation, American National Bankshares Inc. and directors and certain executive officers of American National Bankshares Inc.
	Annex C:			Opinion of Keefe, Bruyette & Woods, Inc.

	Page
QUESTIONS AND ANSWERS ABOUT THE PROPOSED MERGERS AND THE SPECIAL MEETING		1
SUMMARY		8
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS		16
RISK FACTORS		18
Risks Relating to the Mergers		18
Risks Relating to the Combined Company’s Business Following the Mergers		21
THE SPECIAL MEETING		24
Date, Time and Place of the Special Meeting		24
Purpose of the Special Meeting		24
Recommendation of the American National Board of Directors		24
Record Date and Quorum		24
Vote Required; Treatment of Abstentions and Failure to Vote		25
Shares Held by Directors and Executive Officers		25
Voting of Proxies; Incomplete Proxies		25
Revocability of Proxies and Changes to an American National Shareholder’s Vote		26
Solicitation of Proxies		27
Attending the Special Meeting		27
Assistance		27
THE AMERICAN NATIONAL PROPOSALS		28
INFORMATION ABOUT THE COMPANIES		30
THE MERGER		31
Terms of the Merger		31
Background of the Merger		31
American National’s Reasons for the Merger and Recommendation of the American National Board of Directors		38
Opinion of American National’s Financial Advisor		41
Certain Unaudited Prospective Financial Information		52
Atlantic Union’s Reasons for the Merger		55
Governance of Atlantic Union Following the Completion of the Merger		57
Interests of American National’s Directors and Executive Officers in the Merger		57
Potential Payments and Benefits to American National’s Named Executive Officers in Connection with a Change in Control		60
Regulatory Approvals Required for the Mergers		61
Accounting Treatment of the Merger		62
Public Trading Markets		62
Appraisal Rights of American National Shareholders		62
THE MERGER AGREEMENT		63
Structure of the Mergers		63
Treatment of the Restricted Stock Awards		64
Surviving Corporation Governing Documents, Directors and Officers		64
Closing and Effective Time		64