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 30, 2011

Parkvale Financial Corporation

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (412) 373-7200

Not Applicable

(Former name or former address, if changed since last report)

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):

Effective as of 12:01 a.m. on January 1, 2012 (the “Effective Time”), Parkvale Financial Corporation (the “Company”) completed its merger (the “Merger”) with and into F.N.B. Corporation (“FNB”) pursuant to an Agreement and Plan of Merger, dated as of June 15, 2011, by and between FNB and the Company (the “Merger Agreement”). As a result of the consummation of the transactions contemplated by the Merger Agreement, the Company’s separate corporate existence ceased and FNB continued as the surviving corporation. In addition, effective on January 1, 2012, Parkvale Savings Bank, which was a wholly owned subsidiary of the Company, was merged with and into FNB Bank, a wholly owned subsidiary of FNB, with FNB Bank as the surviving institution. As of the Effective Time, each share of common stock of the Company outstanding immediately prior to the Effective Time (other than those to be cancelled in accordance with the Merger Agreement) was converted into and became exchangeable for the right to receive 2.178 shares of FNB common stock (provided, however, that cash will be issued in lieu of fractional shares) (the “Merger Consideration”).

Additional information and details of the Merger Agreement were previously disclosed in the proxy statement/prospectus filed by the Company with the Securities and Exchange Commission (the “SEC”) on November 7, 2011 (SEC File No. 0-17411) (the “Proxy Statement/Prospectus”). Any description of the Merger Agreement is qualified in its entirety by reference to the complete copy of the Merger Agreement which is included as Annex A in the Proxy Statement/Prospectus and is incorporated by reference herein.

The information disclosed in Item 2.01 of this Current Report on Form 8-K is hereby incorporated by reference.

In connection with the consummation of the Merger, on December 30, 2011, the Company notified the Nasdaq Global Market (“Nasdaq”) that, as of the Effective Time, the Company would be merged with and into FNB and each of the shares of common stock of the Company outstanding immediately prior to the Effective Time of the Merger (other than those to be cancelled in accordance with the Merger Agreement) would be converted into and become exchangeable for the right to receive 2.178 shares of FNB common stock (provided, however, that cash will be issued in lieu of fractional shares), and requested that Nasdaq file with the SEC a notification of removal from listing on Form 25 to report that shares of the Company’s common stock are no longer listed on Nasdaq.

As of the Effective Time of the Merger, holders of the Company’s common stock immediately prior to the Effective Time ceased to have any rights as shareholders of the Company and were entitled only to receive the Merger Consideration.

As of the Effective Time, FNB completed its acquisition of the Company in accordance with the Merger Agreement.

As previously disclosed, on June 15, 2011, the Company entered into the Merger Agreement. On December 15, 2011, the Merger Agreement was approved by the Company’s shareholders at the Company’s special meeting of shareholders.

The disclosures under Items 2.01, 3.01 and 3.03 above are incorporated herein by reference.

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.