United States

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 15, 2008

UNION BANKSHARES CORPORATION

(Exact name of registrant as specified in its charter)

211 North Main Street

P.O. Box 446

Bowling Green, Virginia 22427

(Address of principal executive offices, including Zip Code)

Registrant’s telephone number, including area code: (804) 633-5031

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

On December 15, 2008, Union Bankshares Corporation (“the Company”) issued a press release announcing that it has received preliminary approval from the U. S. Treasury to participate in the Treasury’s TARP Capital Purchase Program. The final approval of the Treasury and closing of the transaction is subject to the Treasury’s standard terms, closing conditions and documentation. Upon approval, the Company would issue to the U. S. Treasury up to $59 million of preferred stock and warrants to purchase common stock. The Company expects closing to occur prior to December 31, 2008. A copy of the Company’s press release is attached as Exhibit 99.1 to this report and is incorporated herein by reference.

In addition, on December 16, 2008, the Company sent a letter to its bank account customers and shareholders announcing its preliminary approval from the U.S. Treasury to participate in the Capital Purchase Program. A copy of the Company’s press release is attached as Exhibit 99.2 to this report and is incorporated herein by reference.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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