Exhibit 12.1
Enterprise Financial Services Corp
Statement Regarding Computation of Ratios of Earnings to Fixed Charges and Preferred Stock Dividend Requirement (unaudited)

| Years ended December 31,
($ in thousands) | 2015 |  | 2014 |  | 2013 |  | 2012 |  | 2011
Earnings (1): |  |  |  |  |  |  |  |  |
Income (loss) before income taxes | $ | 58,401 |  |  | $ | 41,044 |  |  | $ | 50,080 |  |  | $ | 42,830 |  |  | $ | 38,225 |
Add: Fixed charges from below | 12,369 |  |  | 14,386 |  |  | 18,137 |  |  | 28,002 |  |  | 33,950 |
Earnings including interest expense on deposits (a) | $ | 70,770 |  |  | $ | 55,430 |  |  | $ | 68,217 |  |  | $ | 70,832 |  |  | $ | 72,175 |
Less: interest expense on deposits | (10,412 | ) |  | (10,487 | ) |  | (11,142 | ) |  | (15,406 | ) |  | (21,658 | )
Earnings excluding interest expense on deposits (b) | $ | 60,358 |  |  | $ | 44,943 |  |  | $ | 57,075 |  |  | $ | 55,426 |  |  | $ | 50,517 |
Fixed charges (1): |  |  |  |  |  |  |  |  |
Interest on deposits | $ | 10,412 |  |  | $ | 10,487 |  |  | $ | 11,142 |  |  | $ | 15,406 |  |  | $ | 21,658 |
Interest on borrowings | 1,957 |  |  | 3,899 |  |  | 6,995 |  |  | 7,761 |  |  | 8,497 |
TARP preferred stock dividends (pre-tax) | — |  |  | — |  |  | — |  |  | 4,835 |  |  | 3,795 |
Fixed charges including interest on deposits (c) | $ | 12,369 |  |  | $ | 14,386 |  |  | $ | 18,137 |  |  | $ | 28,002 |  |  | $ | 33,950 |
Less: interest expense on deposits | (10,412 | ) |  | (10,487 | ) |  | (11,142 | ) |  | (15,406 | ) |  | (21,658 | )
Fixed charges excluding interest expense on deposits (d) | $ | 1,957 |  |  | $ | 3,899 |  |  | $ | 6,995 |  |  | $ | 12,596 |  |  | $ | 12,292 |
Ratio of earnings to combined fixed charges |  |  |  |  |  |  |  |  |
Excluding interest on deposits (b/d) (2) | 30.85x |  |  | 11.53x |  |  | 8.16x |  |  | 4.40x |  |  | 4.11x |
Including interest on deposits (a/c) | 5.72x |  |  | 3.85x |  |  | 3.76x |  |  | 2.53x |  |  | 2.13x |
Ratio of earnings to combined fixed charges and preferred dividends: |  |  |  |  |  |  |  |  |
Excluding interest on deposits (b/d) (2) | 30.85x |  |  | 11.53x |  |  | 8.16x |  |  | 6.52x |  |  | 5.50x |
Including interest on deposits (a/c) | 5.72x |  |  | 3.85x |  |  | 3.76x |  |  | 2.85x |  |  | 2.27x |
(1) As defined in Item 503(d) of Regulation S-K.
(2) The ratio of earnings to fixed charges and preferred dividends, excluding interest on deposits, is being provided as an additional measure to provide comparability to the ratios disclosed by all other issuers of debt securities.