Columbia Banking System (COLB) S-3ASR Automatic shelf registration

EXHIBIT 12.1

Ratios of Earnings to Fixed Charges and Earnings to Combined Fixed Charges and Preferred Stock Dividends

Our historical ratios of earnings to fixed charges and ratio of earnings to combined fixed charges and preferred stock dividends for the periods indicated are set forth below.

	For the Year Ended March 31,				For the Year Ended December 31,
	2015		2014		2014		2013		2012		2011		2010
	(in thousands)				(in thousands)
Income before income taxes	$	35,188	$	28,640	$	117,785	$	87,010	$	63,705	$	65,942	$	33,075
Plus fixed charges:
Interest expense on deposits		748		752		3,005		3,962		5,887		10,478		16,733
Interest expense on borrowings		305		233		989		1,878		3,690		4,057		4,359
Estimated interest component of net rental expense		443		659		2,780		2,839		1,515		1,533		1,500
Fixed charges		1,496		1,644		6,774		8,679		11,092		16,068		22,592
Dividends and accretion on preferred stock		48		18		148		49		—		—		7,611
Ratio of Earnings to Fixed Charges
Including interest on deposits		24.52		18.42		18.39		11.03		6.74		5.10		2.46
Excluding interest on deposits		48.04		33.11		32.25		19.45		13.24		12.80		6.65
Ratio of Earnings to Combined Fixed Charges and Preferred Stock Dividends
Including interest on deposits		23.79		18.23		18.02		10.97		6.74		5.10		2.10
Excluding interest on deposits		45.21		32.47		31.07		19.26		13.24		12.80		3.46