F.N.B. (FNB) S-3ASR Automatic shelf registration

Exhibit 12.1

F.N.B. CORPORATION

COMPUTATIONS OF CONSOLIDATED RATIOS OF EARNINGS TO FIXED CHARGES

(Dollars in thousands)

	Three Months Ended
	March 31,						Year Ended December 31,
	2012			2011			2011			2010			2009			2008			2007
Earnings:
Income before income taxes	$	29,421		$	22,930		$	119,051		$	102,536		$	50,380		$	42,832		$	98,139
Fixed charges, excluding interest on deposits		5,143			6,048			23,402			26,285			41,560			48,312			51,510
Less: Preferred stock dividends		0			0			0			0			(4,085)			0			0
Subtotal		34,564			28,978			142,453			128,821			87,855			91,144			149,649
Interest on deposits		11,958			14,595			53,535			64,524			85,699			111,568			124,276
Total	$	46,522		$	43,573		$	195,988		$	193,345		$	173,554		$	202,712		$	273,925
Fixed charges:
Interest on borrowed funds	$	4,408		$	5,493		$	21,082		$	24,207		$	35,480		$	46,421		$	49,777
Interest component of rental expense		735			555			2,320			2,078			1,995			1,891			1,733
Preferred stock dividends		0			0			0			0			4,085			0			0
Subtotal		5,143			6,048			23,402			26,285			41,560			48,312			51,510
Interest on deposits		11,958			14,595			53,535			64,524			85,699			111,568			124,276
Total	$	17,101		$	20,643		$	76,937		$	90,809		$	127,259		$	159,880		$	175,786
Ratio of earnings to fixed charges:
Excluding interest on deposits		6.72	x		4.79	x		6.09	x		4.90	x		2.34	x		1.89	x		2.91	x
Including interest on deposits		2.72	x		2.11	x		2.55	x		2.13	x		1.41	x		1.27	x		1.56	x
Ratio of earnings to fixed charges and preferred stock dividends:
Excluding interest on deposits		6.72	x		4.79	x		6.09	x		4.90	x		2.11	x		1.89	x		2.91	x
Including interest on deposits		2.72	x		2.11	x		2.55	x		2.13	x		1.36	x		1.27	x		1.56	x