Exhibit 99.1

F.N.B. Corporation Reports Net Income of $23.8 Million for Third Quarter 2011

Continued Revenue Growth and Loan Growth

Hermitage, PA – October 19, 2011 – F.N.B. Corporation (NYSE: FNB) today reported third quarter 2011 financial results. Net income for the third quarter of 2011 was $23.8 million, or $0.19 per diluted share, compared to $22.4 million, or $0.18 per diluted share, in the second quarter of 2011 and $17.2 million, or $0.15 per diluted share, in the third quarter of 2010.

“Results for the third quarter of 2011 demonstrate FNB’s ability to consistently grow revenue, loans and deposits. Revenue growth was achieved for the eighth consecutive quarter and total loan growth was achieved for the ninth consecutive quarter,” said Stephen J. Gurgovits, Chief Executive Officer of F.N.B. Corporation. “The net interest margin was stable and credit quality results continued to be good. The third quarter was another positive quarter for FNB and we are very pleased to deliver increased earnings for our shareholders.”

F.N.B. Corporation’s performance ratios for the third quarter of 2011 were as follows: return on average tangible equity (non-GAAP measure) was 16.23%; return on average equity was 7.79%; return on average tangible assets (non-GAAP measure) was 1.06% and return on average assets was 0.95%. A reconciliation of GAAP measures to non-GAAP measures is included in the tables that accompany this press release.

Third Quarter Results

(All comparisons refer to the second quarter of 2011, except as noted)

Net Interest Income

Net interest income on a fully taxable equivalent basis totaled $82.4 million in the third quarter of 2011, increasing $1.7 million, or 8.4% annualized, primarily as a result of the 4.5% annualized growth in average earning assets. Growth in average earnings assets primarily reflects strong loan growth results. The net interest margin expanded one basis point to 3.79%, reflecting a 7 basis point improvement in the cost of funds that more than offset a 6 basis point lower yield on earning assets.

“We continue to demonstrate our ability to generate consistent loan growth. Growth in the Pennsylvania commercial portfolio for ten consecutive quarters comes largely from market share gains through a disciplined focus on winning new relationships,” said Mr. Gurgovits. “Building these relationships is an important strategy for FNB with the benefits also apparent in the transaction deposit and customer repurchase agreements growth results.”

Average loans for the third quarter totaled $6.7 billion, increasing $126.4 million or 7.6% annualized, with strong growth results in the Pennsylvania commercial portfolio and the

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consumer portfolio. The Pennsylvania commercial portfolio (including commercial leases) grew $79.6 million or 8.7% annualized.

Average consumer loan growth totaled $51.5 million, or 7.4% annualized, driven by strong growth of $39.6 million, or 10.1% annualized, in average home equity lending balances (comprised of lines of credit and direct installment loans). This growth reflects greater consumer demand for these products during the third quarter and the success of promotions and marketing efforts to capitalize on this demand.

Average deposits and customer repurchase agreements totaled $8.1 billion, increasing $20.5 million or 1.0% annualized. Success growing relationship-based transaction deposits and customer repurchase agreements continued, with these average balances increasing $80.2 million, or 5.6% annualized. This growth reflects new client acquisition and customers holding higher average balances. Partially offsetting this growth was a planned decline in time deposits. As of September 30, 2011, FNB’s total customer based-funding remained consistent with June 30, 2011 levels at 96% of total deposits and borrowings.

Non-Interest Income

Non-interest income totaled $29.6 million in the third quarter of 2011, increasing $0.4 million, or 1.3%, with growth in all fee income categories except for wealth management-related revenue. Service charge revenue benefitted from normal seasonality and new account growth. Gain on the sale of loans increased as a result of higher volume given the increased demand for these residential mortgage products in the current low rate environment. Wealth-management related revenue (comprised of securities commissions and fees and trust income) declined primarily as a result of the unfavorable stock market conditions during the third quarter.

Non-Interest Expense

Non-interest expense totaled $69.2 million in the third quarter of 2011, increasing $0.8 million or 1.2%. The increased personnel costs reflect seasonally higher part-time salary expense combined with increased profitability and performance-based accruals for incentive compensation. Additionally, occupancy costs are slightly elevated due to $0.3 million in costs related to damage caused by flooding in northeastern Pennsylvania and other expense includes $0.3 million in merger-related costs. The other expense category also includes higher loan related expenses incurred in conjunction with a home equity loan promotion. Other real estate owned (OREO) costs decreased $1.3 million reflecting lower valuation adjustments including realized gains and losses. The efficiency ratio for the third quarter was 59% compared to 58% in the prior quarter.

Income Tax Expense

The effective tax rate for the third quarter was 26.3%, lower than the 27.9% in the second quarter. The lower rate for the third quarter reflects net adjustments totaling $0.5 million primarily related to the reversal of liabilities for uncertain tax positions under ASC 740 based on a recent Internal Revenue Service directive that provides a safe harbor deduction for certain

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merger-related expenses, partially offset by other adjustments. This tax benefit was partially offset by the $0.6 million ($0.4 million after taxes) in flood and merger-related expenses.

Credit Quality

“We are pleased to report another quarter of good credit quality performance. The Pennsylvania and Regency portfolios, together representing over 97% of the total loan portfolio, both continue to perform consistently well,” remarked Mr. Gurgovits.

The provision for loan losses of $8.6 million was consistent with the prior quarter. Net loan charge-offs for the third quarter equaled 0.53% annualized of average loans with the increase reflecting higher charge-offs in the Florida portfolio related to reappraisals of Florida land-related credits. The ratio of non-performing loans and OREO to total loans and OREO improved 7 basis points to 2.35% at September 30, 2011, reflecting improvements in the Pennsylvania portfolio partially offset by actions taken in the Florida portfolio. The allowance for loan losses to total loans equaled 1.60% and with the credit mark for the acquired portfolio equaled 1.98% at September 30, 2011 (non-GAAP measure).

The Pennsylvania loan portfolio’s credit quality metrics for the third quarter of 2011 continue to reflect consistent and solid performance. The Pennsylvania loan portfolio totaled $6.5 billion at September 30, 2011, representing 95% of the total loan portfolio. Non-performing loans and OREO were $78.3 million or 1.21% of total loans and OREO at September 30, 2011, improving from $86.4 million or 1.36%. The improvement in non-performing loans and OREO primarily reflects the movement of $9.6 million of residential mortgage troubled debt restructurings (TDR’s) to performing status as these loans have demonstrated consistent sustained performance and it is expected at this time that all contractual amounts under the restructured terms will be collected. Past due and non-accrual loans to total loans totaled 1.78% at September 30, 2011, improving slightly from 1.79% at June 30, 2011. Charge-off performance continues to be very good, with net charge-offs for the third quarter improving 9 basis points to 0.25% annualized of average loans, representing the lowest level in ten quarters. The allowance for loan losses to total loans equaled 1.26% and with the credit mark for the acquired portfolio equaled 1.66% at September 30, 2011 (non-GAAP measure).

The Florida loan portfolio totaled $176.6 million, representing 2.6% of the total loan portfolio. Credit quality results for this portfolio included an $8.4 million increase in non-accrual loans primarily as a result of an $8.1 million credit moving to non-accrual status. Net charge-offs previously reserved for of $3.5 million were mainly related to reappraisals of Florida land-related credits. Total land-related exposure totaled $70.0 million and consisted of $50.0 million in loans and $20.0 million in OREO, representing a reduction of $3.9 million or 5.2%.

Capital Position

The Corporation’s capital levels at September 30, 2011 were essentially the same as June 30, 2011 levels and continue to exceed federal bank regulatory agency “well capitalized” thresholds.

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At September 30, 2011, the estimated total risk-based capital ratio was 13.3%, the estimated tier 1 risk-based capital ratio was 11.7% and the leverage ratio was 9.0%. At September 30, 2011, the tangible common equity to tangible assets ratio (non-GAAP measure) was 6.57% compared to 6.50% and the tangible book value per share (non-GAAP measure) grew $0.10 to $4.83.

The dividend payout ratio for the third quarter of 2011 was 65% down from 69%.

Year-to-Date Results

(All comparisons refer to the prior year-to-date period, except as noted)

Year-to-date results for the nine months ended September 30, 2011 include the impact from the Comm Bancorp, Inc. (CBI) acquisition completed on January 1, 2011.

For the nine months ended September 30, 2011, F.N.B. Corporation’s net income totaled $63.3 million, or $0.51 per diluted share, improved from $51.1 million, or $0.45 per diluted share. For the 2011 year-to-date period, return on average tangible equity (non-GAAP measure) totaled 15.70% compared to 14.88%, return on average equity was 7.24% compared to 6.48%, return on average tangible assets (non-GAAP measure) was 0.97% compared to 0.88%, and return on average assets was 0.86% compared to 0.77%.

Net interest income on a fully taxable equivalent basis totaled $242.4 million for the first nine months of 2011, an increase of $25.2 million or 11.6%, reflecting 11.2% growth in average earning assets and a 1 basis point expansion of the net interest margin. The growth in earning assets reflects a combination of organic growth and the CBI acquisition. For the first nine months of 2011, average loans increased $696 million, or 11.7%, with organic growth of 4.8% driven by continued solid market share gains in the Pennsylvania commercial portfolio. Average deposits and customer repurchase agreements grew $868 million, or 12.2%, with organic growth of 4.2% for the first nine months of 2011 due to continued new customer acquisition and higher average balances partially offset by a planned decline in time deposits.

Non-interest income totaled $87.3 million for the first nine months of 2011, a slight increase of $0.8 million, or 1.0%, with results for the first nine months of 2010 benefiting from several items. The first nine months of 2010 included $3.7 million higher recoveries on impaired loans acquired through acquisitions and a $1.6 million gain related to the successful harvesting of a mezzanine financing relationship by F.N.B. Capital Corporation. When adjusting for these two items in the prior year-to-date period and excluding securities gains and other-than-temporary impairment charges, non-interest income improved $6.3 million or 7.8% due to positive results in a number of fee-based businesses. Service charges increased $3.4 million, or 8.0%, reflecting higher volume, organic growth and the expanded customer base due to the CBI acquisition. Fee income on a year-over-year basis also reflects a $2.6 million, or 18.1%, increase in wealth management-related revenue as a result of revenue-generating initiatives, more favorable market conditions and organic growth. Additionally, swap fee revenue included in other income

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doubled to $3.2 million in the first nine months of 2011 given the successful commercial loan growth results and continued low interest rate environment.

Non-interest expense totaled $212.1 million for the first nine months of 2011, an increase of $19.4 million, or 10.0%, due to adding CBI-related operating costs and $4.6 million in one-time merger-related costs. Expected cost savings related to the acquisition were fully phased in at the beginning of the second quarter of 2011. Additionally, OREO-related costs increased $2.5 million in the first nine months of 2011 due to current valuation adjustments and property maintenance costs related to the Florida portfolio. On a year-to-date basis, F.N.B. Corporation’s efficiency ratio improved to 60% from 61%.

Credit quality results significantly improved for the first nine months of 2011. Provision for loan losses was $25.4 million for the first nine months of 2011, improving $11.2 million mainly due to an $8.1 million lower provision for the Florida portfolio. Net charge-off results for the first nine months of 2011 improved 9 basis points to 0.46% annualized of total loans and reflect continued solid performance for the Pennsylvania and Regency portfolios and improvement in the Florida portfolio. The ratio of the allowance for loan losses to total loans equaled 1.60% at September 30, 2011, compared to 1.94% at September 30, 2010, with the decline principally reflecting the impact of the accounting treatment required for loans acquired in connection with the CBI acquisition. The ratio of the allowance for loan losses plus the credit mark for the acquired portfolio to total loans plus the credit mark equaled 1.98% at September 30, 2011.

Other Highlights

First National Bank of Pennsylvania was recently named as one of “Pittsburgh’s Top Workplaces 2011” by The Pittsburgh Post-Gazette. Recognition as a Top Workplace is awarded based on feedback gathered from an employee survey that measures employee response to leadership, values that drive the organization, attitude about the company’s future and more.

Conference Call

F.N.B. Corporation will host its quarterly conference call to discuss third quarter of 2011 financial results on Thursday, October 20, 2011, at 8:00 AM EDT. Participating callers may access the call by dialing (888) 364-3105 or (719) 325-2192 for international callers; the confirmation number is 4796847. The listen-only audio Webcast may be accessed through the “Shareholder and Investor Relations” section of the Corporation’s Web site at www.fnbcorporation.com.

A replay of the call will be available from 11:00 AM EDT the day of the call until midnight EDT on Thursday, October 27, 2011. The replay is accessible by dialing (877) 870-5176 or (858) 384-5517 for international callers; the confirmation number is 4796847. The call transcript and Webcast will be available on the “Shareholder and Investor Relations” section of F.N.B. Corporation’s Web site at www.fnbcorporation.com.

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About F.N.B. Corporation

F.N.B. Corporation, headquartered in Hermitage, PA, is a diversified financial services company with total assets of $9.95 billion. F.N.B. Corporation is a leading provider of commercial and retail banking, leasing, wealth management, insurance, merchant banking and consumer finance services in Pennsylvania and Ohio, where it owns and operates First National Bank of Pennsylvania, First National Trust Company, First National Investment Services Company, LLC, F.N.B. Investment Advisors, Inc., First National Insurance Agency, LLC, F.N.B. Capital Corporation, LLC, Regency Finance Company and F.N.B. Commercial Leasing. It also operates consumer finance offices in Kentucky and Tennessee.

Forward-looking Statements

This press release of F.N.B. Corporation and the reports F.N.B. Corporation files with the Securities and Exchange Commission often contain “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act, relating to present or future trends or factors affecting the banking industry and, specifically, the financial operations, markets and products of F.N.B. Corporation. Forward-looking statements are typically identified by words such as “believe”, “plan”, “expect”, “anticipate”, “intend”, “outlook”, “estimate”, “forecast”, “will”, “should”, “project”, “goal”, and other similar words and expressions. These forward-looking statements involve certain risks and uncertainties. There are a number of important factors that could cause F.N.B. Corporation’s future results to differ materially from historical performance or projected performance. These factors include, but are not limited to: (1) a significant increase in competitive pressures among financial institutions; (2) changes in the interest rate environment that may reduce net interest margins; (3) changes in prepayment speeds, loan sale volumes, charge-offs and loan loss provisions; (4) general economic conditions; (5) various monetary and fiscal policies and regulations of the U.S. Government that may adversely affect the businesses in which F.N.B. Corporation is engaged; (6) technological issues which may adversely affect F.N.B. Corporation’s financial operations or customers; (7) changes in the securities markets; (8) risk factors mentioned in the reports and registration statements F.N.B. Corporation files with the Securities and Exchange Commission (SEC) which are available on our shareholder and investor relations website at www.fnbcorporation.com and on the SEC website at www.sec.gov; (9) housing prices; (10) job market; (11) consumer confidence and spending habits and (12) estimates of fair value of certain F.N.B. Corporation assets and liabilities. All information provided in this release and in the attachments is based on information only as of the date provided and presently available and F.N.B. Corporation undertakes no obligation to revise these forward-looking statements or to reflect events or circumstances after the date of this press release.

ADDITIONAL INFORMATION ABOUT THE MERGER

F.N.B. Corporation filed a registration statement on Form S-4 with the SEC on September 28, 2011. The registration statement included a proxy statement/prospectus and other relevant documents filed with the SEC in connection with the merger.

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SHAREHOLDERS OF PARKVALE FINANCIAL CORPORATION ARE ADVISED TO READ THE PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, BECAUSE THEY CONTAIN IMPORTANT INFORMATION.

The proxy statement/prospectus and other relevant materials, and any other documents F.N.B. Corporation has filed with the SEC, may be obtained free of charge at the SEC’s website at www.sec.gov. In addition, investors and security holders may obtain free copies of the documents F.N.B. Corporation has filed with the SEC by contacting James Orie, F.N.B. Corporation, One F.N.B. Boulevard, Hermitage, PA 16148, telephone: (724) 983-3317 or for Parkvale Financial Corporation by contacting Gilbert A. Riazzi, Chief Financial Officer, 4220 William Penn Highway, Monroeville, PA 15146, telephone: (412) 373-4804.

Parkvale Financial Corporation and its directors, executive officers and other members of its management and employees may be deemed to be participants in the solicitation of proxies from its shareholders in connection with the proposed merger. Information concerning such participants’ ownership of Parkvale Financial Corporation common stock are set forth in the proxy statement/prospectus relating to the merger when it becomes available. This communication does not constitute an offer of any securities for sale.

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Analyst/Institutional Investor Contact:

Cynthia Christopher 724-983-3429

724-815-3926 (cell)

christoc@fnb-corp.com

Media Contact:

Jennifer Reel 724-983-4856

724-699-6389 (cell)

reel@fnb-corp.com

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F.N.B. CORPORATION

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F.N.B. CORPORATION

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F.N.B. CORPORATION

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