EXHIBIT 99.1

For more information contact:

Jerry Mueller, Senior Vice President (314) 512-7251

Ann Marie Mayuga, AMM Communications (314) 485-9499

ENTERPRISE FINANCIAL REPORTS THIRD QUARTER 2015 RESULTS

Reported Highlights

• Net income of $0.48 per diluted share, increased 12% over the linked quarter, and 17% compared to the third quarter of 2014

• Portfolio loans grow 9% on an annualized basis in the quarter, and 13% from the prior year period

• 14% cash dividend increase to $0.08 per share in the fourth quarter of 2015 from $0.07 per share in the third quarter of 2015

Core Highlights¹ 

• Core net income of $0.44 per diluted share, increased16% over the linked quarter, and 19% compared to the prior year period

• Core net interest income increased 3% in the quarter, and 9% from the prior year period

• Core efficiency ratio of 58.6% for the quarter

St. Louis, October 22, 2015. Enterprise Financial Services Corp (NASDAQ: EFSC) (the “Company”) reported net income of $9.7 million for the quarter ended September 30, 2015, an increase of $1.0 million, or 11%, as compared to the linked second quarter. Net income per diluted share was $0.48 for the quarter ended September 30, 2015, an increase of 12% compared to $0.43 per diluted share for the linked second quarter due to an increase in net interest income and lower provision for loan losses on portfolio loans. Third quarter 2015 net income was 18%higher than the $8.2 million reported in the prior year period, and diluted earnings per share were 17%higher than the $0.41 reported a year ago. The increase in net income over the prior year was primarily due to an increase in net interest income from strong loan growth and a decrease in noninterest expenses from improved expense control initiatives.

On a core basis¹, the Company reported net income of $8.9 million, or $0.44 per diluted share, for the quarter ended September 30, 2015, compared to $7.7 million, or $0.38 per diluted share, in the linked second quarter.  The increase was due to an increase in net interest income from strong loan growth and a decrease in provision for loan loss from improved credit quality. Third quarter 2015 core net income increased19% from $7.5 million for the prior year period, and diluted core earnings per share grew19% from $0.37 for the prior year period. The increase was primarily due to increases in earning asset balances driving growth in core net interest income.

The Company's Board approved an additional one cent per common share increase in the Company’s quarterly dividend to $0.08 per common share from $0.07 for the fourth quarter of 2015, payable on December 31, 2015 to shareholders of record as of December 15, 2015.

Peter Benoist, President and Chief Executive Officer, commented, “Enterprise continued to deliver strong results in the third quarter, with reported net income rising 11%, producing a Return on average assets of 1.13% and Return on average tangible common equity of 12.65%.”

"We continue to execute on our operating strategies,” noted Benoist, “focusing on growing both portfolio loans and core deposits. We’re achieving loan growth through gaining market share and also leveraging our expertise in attractive niche segments within and beyond our geographic footprint. Similarly, we have experienced continued success in targeted market segments and specific niches for deposit growth. As a result, over the past twelve

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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months we’ve increased portfolio loans by 13%, deposits by 12%, and net interest income by 9%. Our core net interest margin is equivalent to the prior year level and total operating expenses are 6% lower than a year ago.”

“With reported earnings up 18% from the prior year quarter and core earnings up 19%, coupled with very strong capital levels, the Board has authorized three dividend increases this year totaling 52%, demonstrating our confidence in the Company’s strategy and enhanced earnings profile,” said Benoist.

Net Interest Income

Net interest income in the third quarter increased$0.7 million from the linked second quarter and $2.6 million from the prior year period due primarily to lower interest expense from the payoff of higher cost debt in the prior year and an increase in portfolio loan balances. The net interest margin, on a fully tax equivalent basis, was 3.77% for the third quarter, compared to 3.85% in the linked second quarter, and 3.75% in the third quarter of 2014.

The yield on Portfolio loans was 4.16% in the third quarter, a one basis point decline from the linked second quarter and six basis points lower than the third quarter of 2014. In the third quarter of 2015, the yield on Purchase credit impaired ("PCI") loans was 19.41%, as compared to 18.33% in the linked quarter and 14.67% in the prior year period.

The cost of interest-bearing deposits declinedtwo basis points to 0.50% in the third quarter of 2015 from the linked second quarter, and was eight basis points lower than the third quarter of 2014, primarily from lower rates on time deposit balances. The cost of interest-bearing liabilities declinedone basis point as compared to the linked quarter to 0.53% and decreased11 basis points from the third quarter of 2014. The improvement was primarily due to the prepayment of $50 million of FHLB borrowings in December 2014 and the aforementioned improvement in deposit costs.

Core net interest margin¹, defined as the net interest margin (fully tax equivalent), including contractual interest on PCI loans but excluding the incremental accretion on these loans, was as follows:

	For the Quarter ended
($ in thousands)	September 30, 2015		June 30, 2015		March 31, 2015		December 31, 2014		September 30, 2014
Core net interest margin1	3.41	%	3.46	%	3.46	%	3.45	%	3.41	%
Core net interest income1	27,087		26,277		25,587		25,667		24,865

Core net interest income¹increased9% compared to the prior year period due to strong portfolio loan growth and managed decreases in the cost of interest-bearing liabilities as discussed above. Core net interest income increased by $0.8 million to $27.1 million, and core net interest margin¹ declined five basis points to 3.41%, when compared to the linked second quarter. Approximately four basis points of the decline in Core net interest margin was due to a strong 18.0% annualized increase in deposit balances from our deposit gathering efforts and resultant increase in cash and shorter duration assets. Core net interest margin remained stable from the prior year quarter primarily due to the effect of the FHLB debt prepayment in December 2014 and loan growth improving our earning asset mix, offset by continued pressure on portfolio loan yields and reductions in PCI loan balances, as those balances continue to run-off. Pressure on loan yields and continued reductions in PCI loan balances could lead to a modest decline in core net interest margin in the remaining three months of 2015 and into 2016.

Portfolio loans

Portfolio loans increased to $2.6 billion at September 30, 2015, increasing$60 million, or 9% on an annualized basis, when compared to the linked quarter. On a year over year basis, portfolio loans increased$307 million, or 13%. The Company continues to expect loan growth at or above 10% for 2015.

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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Commercial and industrial ("C&I") loans increased$36.1 million during the third quarter of 2015 compared to the linked second quarter. C&I loans represented 53% of the Company's loan portfolio at September 30, 2015, relatively consistent with June 30, 2015. C&I loans grew$199 million, or 17%, since September 30, 2014. During the 12 months ended September 30, 2015, the Company also grew loans in all other major categories.

The Company continues to focus on originating high-quality C&I relationships, as they typically have variable interest rates and allow for cross selling opportunities involving other banking products. Our specialized market segments, particularly enterprise value lending and life insurance premium finance, have contributed to the growth in the C&I category. C&I loan growth also supports our efforts to maintain the Company's asset sensitive interest rate risk position. At September 30, 2015, 62% of our portfolio loans had variable interest rates.

PCI loans and other real estate covered under FDIC loss share agreements

PCI loans totaled $83.7 million at September 30, 2015, a decrease of $3.9 million, or 4%, from the linked second quarter, and $30.1 million, or 26%, from the prior year period, primarily as a result of principal paydowns and accelerated loan payoffs.

Other real estate covered under FDIC loss share agreements at September 30, 2015 was $6.8 million, a 14%decrease from $7.9 million at June 30, 2015. During the third quarter of 2015, the Company sold $1.7 million of other real estate, resulting in a negligible net gain.

The Company remeasures contractual and expected cash flows on PCI loans on a periodic basis. When the remeasurement process results in a decrease in expected cash flows due to an increase in expected credit losses, impairment is recorded through the provision for loan losses. Similarly, when expected credit losses decrease in the remeasurement process, prior recorded impairment is reversed before the yield is increased prospectively. Concurrently, the FDIC loss share receivable is adjusted to reflect anticipated future cash to be received from the FDIC. In the third quarter of 2015, $0.2 million reversal of provision for loan losses was recorded for certain loan pools. Any provision or reversal of provision would be partially offset through noninterest income by a change in the FDIC loss share receivable.

Actual cash collections in excess of expected cash flows that represent accelerated loan payoffs result in the recognition of income, but also generally result in a decrease in the FDIC loss share receivable. These cash flows are, by their nature, unpredictable and can vary significantly period to period. Actual cash collections in excess of expected cash flows from loan payoffs and real estate sales in the third quarter resulted in accelerated discount income of $1.6 million, which was partially offset by a decrease in the FDIC loss share receivable.

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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The following table illustrates the financial contribution of PCI loans and other real estate covered under FDIC loss share agreements for the most recent five quarters:

	For the Quarter ended
(in thousands) income/(expense)	September 30, 2015			June 30, 2015			March 31, 2015			December 31, 2014			September 30, 2014
Contractual interest income	$	1,248		$	1,209		$	1,539		$	1,840		$	1,701
Accelerated cash flows and other incremental accretion	2,919			3,003			3,458			5,149			2,579
Estimated funding cost	(293		)	(329		)	(317		)	(326		)	(314		)
Total net interest income	3,874			3,883			4,680			6,663			3,966
Provision reversal/(Provision) for loan losses	227			—			3,270			(126		)	1,877
Gain/(loss) on sale of other real estate	31			10			(15		)	195			(45		)
Change in FDIC loss share receivable	(1,241		)	(945		)	(2,264		)	(1,781		)	(2,374		)
Change in FDIC clawback liability	(298		)	(50		)	(412		)	(141		)	(1,028		)
Other expenses	(287		)	(378		)	(471		)	(541		)	(731		)
PCI assets income before income tax expense	$	2,306		$	2,520		$	4,788		$	4,269		$	1,665

At September 30, 2015, the remaining accretable yield on the portfolio was estimated to be$26 million and the non-accretable difference was approximately $35 million. Absent further cash flow accelerations or pool impairment, the Company currently estimates average PCI loan balances to be approximately $80 million and income before tax expense on PCI assets will be approximately $11 million to $13 million in 2015, inclusive of the first nine months of 2015.

Asset quality for portfolio loans and other real estate

The following table presents the categories of nonperforming assets and related ratios for the most recent five quarters:

	For the Quarter ended
(in thousands)	September 30, 2015			June 30, 2015			March 31, 2015			December 31, 2014			September 30, 2014
Nonperforming loans	$	9,123		$	17,498		$	15,143		$	22,244		$	18,212
Other real estate not covered under FDIC loss share	1,575			1,933			2,024			1,896			2,261
Nonperforming assets	$	10,698		$	19,431		$	17,167		$	24,140		$	20,473
Nonperforming loans to total loans	0.35		%	0.69		%	0.62		%	0.91		%	0.79		%
Nonperforming assets to total assets	0.30		%	0.58		%	0.52		%	0.74		%	0.64		%
Net charge-offs (recoveries)	$	113		$	672		$	1,478		$	582		$	(311	)

Nonperforming loans decreased48% to $9.1 million at September 30, 2015, from $17.5 million at June 30, 2015, and decreased50% from $18.2 million at September 30, 2014. During the quarter ended September 30, 2015, there were $0.8 million of charge-offs, $10.4 million of other principal reductions, no assets transferred to other real estate, $2.8 million of additions to nonperforming loans, and no assets transferred to performing. The additions to nonperforming loans consisted of six unrelated accounts. Other principal reductions of $10.4 million consist of $3.1 million of principal payments, and $7.3 million of proceeds from the sales of collateral.

The Company's allowance for loan losses was 1.24% of loans at September 30, 2015, representing 354% of nonperforming loans, as compared to 1.25% at June 30, 2015, representing 182% of nonperforming loans, and 1.25%

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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at September 30, 2014, representing 158% of nonperforming loans. The increase in the ratio of allowance for loan losses to nonperforming loans is primarily due to the 48% decrease in nonperforming loans discussed previously.

Deposits

Total deposits at September 30, 2015 were $2.8 billion, an increase of $122 million, or 18% on an annualized basis, from June 30, 2015, and $304 million, or 12%, from September 30, 2014. The positive trends in deposits reflect enhanced deposit gathering efforts in both commercial and business banking.

Noninterest-bearing deposits increased$33.5 million compared to June 30, 2015 and decreased$4.0 million compared to the quarter ended September 30, 2014. The composition of Noninterest-bearing deposits remained relatively stable at 25% of total deposits at September 30, 2015, from June 30, 2015, and declined compared to 28% of total deposits at September 30, 2014. The total cost of deposits remained stable at 0.39% compared to June 30, 2015, and declined three basis points since September 30, 2014.

Noninterest income

Deposit service charges for the third quarter of 2015 of $2.0 millionincreased by 2% compared to the linked quarter, and grew13% compared to the prior year quarter partially due to growth in deposit relationships. Additionally, Wealth management revenues were relatively stable at $1.8 million compared to the linked second quarter and the prior year period.

Trust assets under management were $849 million at September 30, 2015, a decrease of $41 million, or 5%, when compared to the linked period ended June 30, 2015, and were relatively stable when compared to the prior year period. The decrease in Trust assets under management as compared to the linked quarter was largely due to market depreciation, offset by growth in new customers.

Trust assets under administration were $1.3 billion at September 30, 2015, a decrease of $179 million, or 12%, when compared to the linked quarter, and a decrease of $128 million, or 9%, when compared to the prior year period ended September 30, 2014.

Gains from state tax credit brokerage activities, net of fair value market adjustments on tax credit assets and related interest rate hedges, were $0.3 million for the third quarter of 2015, compared to $0.1 million for the linked second quarter, and $0.2 million in the third quarter of 2014. Sales of state tax credits can vary by quarter, but generally occur in the first and fourth quarters of the year depending on client demand and availability of the tax credits.

Other noninterest income of $1.8 million decreased 38% from the linked quarter, and decreased 40% from the prior year period. The decrease from the linked quarter was due to a decline in allocation fees from tax credit projects and fees earned from recoveries. During the third quarter of 2014, the Company recorded a $0.9 million closing fee associated with the payoff of a Commercial real estate loan. The fee is excluded from core noninterest income. On a core basis, other noninterest income was relatively flat compared to the third quarter of 2014.

Noninterest Expenses

Noninterest expenses were $19.9 million for the quarter ended September 30, 2015, compared to $19.5 million for the quarter ended June 30, 2015, and $21.1 million for the quarter ended September 30, 2014. Core noninterest expenses¹, which exclude certain non-comparable items and expenses directly related to PCI loans and assets covered under loss share agreements, were $19.3 million for the quarter ended September 30, 2015, compared to $19.0 million for the linked quarter and $19.3 million for the prior year period.

The Company's Core efficiency ratio¹ was 58.6% for the quarter ended September 30, 2015, compared to 57.6% for the linked quarter, and 62.8% for the prior year period, and reflects lower legal expenses on problem loans, overall expense management and revenue growth trends.

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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The Company anticipates total noninterest expenses to be between $19 million and $21 million per quarter for the remainder of 2015 and throughout 2016.

Other Business Results

The total risk based capital ratio¹ was 12.56% at September 30, 2015, compared to 12.68% at June 30, 2015, and 13.61% at September 30, 2014. The Company's Common equity tier 1 capital ratio¹ was 9.60% at September 30, 2015, compared to 9.66% at June 30, 2015, and 10.29% at September 30, 2014. The tangible common equity ratio¹ was 8.90% at September 30, 2015, versus 8.94% at June 30, 2015, and 8.63% at September 30, 2014.

The total risk based capital and Common equity tier 1 ratios declined from the prior year period mainly due to the impact of the new regulatory guidelines under Basel III. The decrease in the tangible common equity ratio as compared to the prior quarter was mainly due to asset growth out-pacing earnings, offset by an increase in the net unrealized gain on the investment portfolio. Capital ratios for the current quarter are based on the Company’s interpretations of the Basel III regulatory capital framework as applied to the Company’s current businesses and operations and are subject to, among other things, completion and filing of the Company’s regulatory reports and ongoing regulatory review and implementation guidance. The attached tables contain a reconciliation of these ratios to U.S. GAAP financial measures.

The Company's effective tax rate was 32.7% for the quarter ended September 30, 2015 compared to 35.3% for the quarter ended June 30, 2015 and 34.9% for the quarter ended September 30, 2014. The decrease as compared to the prior quarter was mainly due to lower state income tax expense, including $0.3 million of state tax refunds related to prior years.

Use of Non-GAAP Financial Measures¹ 

The Company's accounting and reporting policies conform to generally accepted accounting principles in the United States (“GAAP”) and the prevailing practices in the banking industry. However, the Company provides other financial measures, such as Core net income margin and other Core performance measures, tangible common equity ratio and Common equity tier 1 capital ratio, in this release that are considered “non-GAAP financial measures.” Generally, a non-GAAP financial measure is a numerical measure of a company's financial performance, financial position or cash flows that exclude (or include) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP.

The Company considers its Core performance measures presented in this earnings release and the included tables as important measures of financial performance, even though they are non-GAAP measures, as they provide supplemental information by which to evaluate the impact of PCI loans and related income and expenses, the impact of certain non-comparable items, and the Company's operating performance on an ongoing basis. Core performance measures include contractual interest on PCI loans but exclude incremental accretion on these loans. Core performance measures also exclude the Change in FDIC receivable, Gain or loss of other real estate covered under FDIC loss share agreements and expenses directly related to the PCI loans and other assets covered under FDIC loss share agreements. Core performance measures also exclude certain other income and expense items the Company believes to be not indicative of or useful to measure the Company's operating performance on an ongoing basis. The attached tables contain a reconciliation of these Core performance measures to the GAAP measures. The Company believes that the tangible common equity and the Common equity tier 1 capital ratios provide useful information to investors about the Company's capital strength even though they are considered to be non-GAAP financial measures and are not part of the regulatory capital requirements to which the Company is subject.

The Company believes these non-GAAP measures and ratios, when taken together with the corresponding GAAP measures and ratios, provide meaningful supplemental information regarding the Company's performance and capital strength. The Company's management uses, and believes that investors benefit from referring to, these non-GAAP measures and ratios in assessing the Company's operating results and related trends and when forecasting future periods. However, these non-GAAP measures and ratios should be considered in addition to, and not as a substitute for or preferable to, ratios prepared in accordance with GAAP. In the tables below, the Company has provided a reconciliation

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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of, where applicable, the most comparable GAAP financial measures and ratios to the non-GAAP financial measures and ratios, or a reconciliation of the non-GAAP calculation of the financial measure for the periods indicated.

The Company will host a conference call and webcast at 2:30 p.m. Central time on Thursday, October 22, 2015. During the call, management will review the third quarter of 2015 results and related matters. This press release as well as a related slide presentation will be accessible on Enterprise Financial Services Corp's website at www.enterprisebank.com under “Investor Relations” beginning prior to the scheduled broadcast of the conference call. The call can be accessed via this same website page, or via telephone at 1-888-466-4462 (Conference ID #2112453.) A recorded replay of the conference call will be available on the website beginning two hours after the call's completion. The telephone replay will be available at 1-888-203-1112 (replay passcode #2112453.) The replays will be available for approximately two weeks following the conference call.

Enterprise Financial Services Corp operates commercial banking and wealth management businesses in metropolitan St. Louis, Kansas City, and Phoenix. The Company is primarily focused on serving the needs of privately held businesses, their owner families, executives and professionals.

# ##

Readers should note that in addition to the historical information contained herein, this press release contains forward-looking statements, including but not limited to statements about the Company's plans, expectations and projections of future financial and operating results, which are inherently subject to risks and uncertainties that could cause actual results to differ materially from those contemplated from such statements. We use the words “expect” and “intend” and variations of such words and similar expressions in this communication to identify such forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, credit risk, changes in the appraised valuation of real estate securing impaired loans, outcomes of litigation and other contingencies, exposure to general and local economic conditions, risks associated with rapid increases or decreases in prevailing interest rates, consolidation in the banking industry, competition from banks and other financial institutions, our ability to attract and retain relationship officers and other key personnel, burdens imposed by federal and state regulation, changes in regulatory requirements, changes in accounting regulation or standards applicable to banks, as well as other risk factors described in the Company's 2014 Annual Report on Form 10-K and other reports filed with the Securities and Exchange Commission. Forward-looking statements speak only as of the date they are made, and the Company undertakes no obligation to update them in light of new information or future events unless required under the federal securities laws.

¹ A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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ENTERPRISE FINANCIAL SERVICES CORP

CONSOLIDATED FINANCIAL SUMMARY (unaudited)

	For the Quarter ended															For the Nine Months ended
(in thousands, except per share data)	Sep 30, 2015			Jun 30, 2015			Mar 31, 2015			Dec 31, 2014			Sep 30, 2014			Sep 30, 2015			Sep 30, 2014
EARNINGS SUMMARY
Net interest income	$	30,006		$	29,280		$	29,045		$	30,816		$	27,444		$	88,331		$	86,552
Provision for loan losses - portfolio loans	599			2,150			1,580			1,968			66			4,329			2,441
Provision (provision reversal) for loan losses - purchase credit impaired loans	(227		)	—			(3,270		)	126			(1,877		)	(3,497		)	957
Noninterest income	4,729			5,806			3,583			4,852			4,452			14,118			11,779
Noninterest expense	19,932			19,458			19,950			24,795			21,121			59,340			62,668
Income before income tax expense	14,431			13,478			14,368			8,779			12,586			42,277			32,265
Income tax expense	4,722			4,762			5,022			2,812			4,388			14,506			11,059
Net income	$	9,709		$	8,716		$	9,346		$	5,967		$	8,198		$	27,771		$	21,206
Diluted earnings per share	$	0.48		$	0.43		$	0.46		$	0.30		$	0.41		$	1.37		$	1.07
Return on average assets	1.13		%	1.06		%	1.16		%	0.73		%	1.02		%	1.11		%	0.91		%
Return on average common equity	11.38		%	10.56		%	11.78		%	7.50		%	10.62		%	11.24		%	9.54		%
Return on average tangible common equity	12.65		%	11.77		%	13.19		%	8.43		%	11.98		%	12.53		%	10.83		%
Net interest margin (fully tax equivalent)	3.77		%	3.85		%	3.92		%	4.13		%	3.75		%	3.84		%	4.05		%
Efficiency ratio	57.38		%	55.46		%	61.14		%	69.52		%	66.22		%	57.92		%	63.73		%
CORE PERFORMANCE SUMMARY1
Net interest income	$	27,087		$	26,277		$	25,587		$	25,667		$	24,865		$	78,951		$	72,771
Provision for loan losses	599			2,150			1,580			1,968			66			4,329			2,441
Noninterest income	5,939			6,741			5,839			6,438			5,926			18,519			18,110
Noninterest expense	19,347			19,030			19,068			20,170			19,347			57,445			59,199
Income before income tax expense	13,080			11,838			10,778			9,967			11,378			35,696			29,241
Income tax expense	4,204			4,134			3,647			3,264			3,926			11,985			9,901
Net income	$	8,876		$	7,704		$	7,131		$	6,703		$	7,452		$	23,711		$	19,340
Diluted earnings per share	$	0.44		$	0.38		$	0.35		$	0.33		$	0.37		$	1.17		$	0.97
Return on average assets	1.03		%	0.93		%	0.88		%	0.82		%	0.93		%	0.95		%	0.83		%
Return on average common equity	10.41		%	9.34		%	8.99		%	8.43		%	9.65		%	9.59		%	8.70		%
Return on average tangible common equity	11.56		%	10.41		%	10.06		%	9.47		%	10.89		%	10.70		%	9.88		%
Net interest margin (fully tax equivalent)	3.41		%	3.46		%	3.46		%	3.45		%	3.41		%	3.44		%	3.42		%
Efficiency ratio	58.58		%	57.64		%	60.67		%	62.83		%	62.83		%	58.94		%	65.14		%
1 A non-GAAP measure. Refer to discussion & reconciliation of these measures in the accompanying financial tables.

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ENTERPRISE FINANCIAL SERVICES CORP

CONSOLIDATED FINANCIAL SUMMARY (unaudited) (continued)

	For the Quarter ended															For the Nine Months ended
(in thousands, except per share data)	Sep 30, 2015			Jun 30, 2015			Mar 31, 2015			Dec 31, 2014			Sep 30, 2014			Sep 30, 2015			Sep 30, 2014
INCOME STATEMENTS
NET INTEREST INCOME
Total interest income	$	33,180		$	32,352		$	32,151		$	34,385		$	31,036		$	97,683		$	97,369
Total interest expense	3,174			3,072			3,106			3,569			3,592			9,352			10,817
Net interest income	30,006			29,280			29,045			30,816			27,444			88,331			86,552
Provision for portfolio loans	599			2,150			1,580			1,968			66			4,329			2,441
Provision (provision reversal) for purchase credit impaired loans	(227		)	—			(3,270		)	126			(1,877		)	(3,497		)	957
Net interest income after provision for loan losses	29,634			27,130			30,735			28,722			29,255			87,499			83,154
NONINTEREST INCOME
Wealth management revenue	1,773			1,778			1,740			1,751			1,754			5,291			5,191
Deposit service charges	2,044			1,998			1,856			1,864			1,812			5,898			5,317
Gain on sale of other real estate	32			9			20			17			114			61			1,514
State tax credit activity, net	321			74			674			1,392			156			1,069			860
Gain on sale of investment securities	—			—			23			—			—			23			—
Change in FDIC loss share receivable	(1,241		)	(945		)	(2,264		)	(1,781		)	(2,374		)	(4,450		)	(7,526		)
Other income	1,800			2,892			1,534			1,609			2,990			6,226			6,423
Total noninterest income	4,729			5,806			3,583			4,852			4,452			14,118			11,779
NONINTEREST EXPENSE
Employee compensation and benefits	11,475			11,274			11,513			11,350			11,913			34,262			35,882
Occupancy	1,605			1,621			1,694			1,528			1,683			4,920			4,998
FDIC clawback	298			50			412			141			1,028			760			1,060
FHLB prepayment penalty	—			—			—			2,936			—			—			—
Facilities disposal charge	—			—			—			1,004			—			—			—
Other	6,554			6,513			6,331			7,836			6,497			19,398			20,728
Total noninterest expense	19,932			19,458			19,950			24,795			21,121			59,340			62,668
Income before income tax expense	14,431			13,478			14,368			8,779			12,586			42,277			32,265
Income tax expense	4,722			4,762			5,022			2,812			4,388			14,506			11,059
Net income	$	9,709		$	8,716		$	9,346		$	5,967		$	8,198		$	27,771		$	21,206
Basic earnings per share	$	0.49		$	0.44		$	0.47		$	0.30		$	0.41		$	1.39		$	1.07
Diluted earnings per share	0.48			0.43			0.46			0.30			0.41			1.37			1.07

9

ENTERPRISE FINANCIAL SERVICES CORP

CONSOLIDATED FINANCIAL SUMMARY (unaudited) (continued)

	At the Quarter ended
(in thousands)	Sep 30, 2015		Jun 30, 2015		Mar 31, 2015		Dec 31, 2014		Sep 30, 2014
BALANCE SHEETS
ASSETS
Cash and due from banks	$	46,775	$	49,498	$	56,420	$	42,903	$	54,113
Interest-earning deposits	81,115		51,298		43,913		63,093		74,999
Debt and equity investments	530,577		465,133		467,343		463,168		471,875
Loans held for sale	4,275		5,446		7,843		4,033		4,899
Portfolio loans	2,602,156		2,542,555		2,435,559		2,433,916		2,294,905
Less: Allowance for loan losses	32,251		31,765		30,288		30,185		28,800
Portfolio loans, net	2,569,905		2,510,790		2,405,271		2,403,731		2,266,105
Purchase credit impaired loans, net of the allowance for loan losses	72,397		76,050		83,163		83,693		98,318
Total loans, net	2,642,302		2,586,840		2,488,434		2,487,424		2,364,423
Other real estate not covered under FDIC loss share	1,575		1,933		2,024		1,896		2,261
Other real estate covered under FDIC loss share	6,795		7,909		3,560		5,944		8,826
Fixed assets, net	14,395		14,726		14,911		14,753		18,054
State tax credits held for sale	48,207		42,062		42,411		38,309		45,631
FDIC loss share receivable	8,619		10,332		11,644		15,866		22,039
Goodwill	30,334		30,334		30,334		30,334		30,334
Intangible assets, net	3,323		3,595		3,880		4,164		4,453
Other assets	98,249		101,972		102,578		105,116		107,683
Total assets	$	3,516,541	$	3,371,078	$	3,275,295	$	3,277,003	$	3,209,590
LIABILITIES AND SHAREHOLDERS' EQUITY
Noninterest-bearing deposits	$	691,758	$	658,258	$	680,997	$	642,930	$	695,804
Interest-bearing deposits	2,122,205		2,033,300		1,993,634		1,848,580		1,813,960
Total deposits	2,813,963		2,691,558		2,674,631		2,491,510		2,509,764
Subordinated debentures	56,807		56,807		56,807		56,807		56,807
Federal Home Loan Bank advances	75,000		73,000		6,000		144,000		120,000
Other borrowings	194,684		188,546		186,864		239,883		187,122
Other liabilities	32,524		28,737		24,884		28,562		27,143
Total liabilities	3,172,978		3,038,648		2,949,186		2,960,762		2,900,836
Shareholders' equity	343,563		332,430		326,109		316,241		308,754
Total liabilities and shareholders' equity	$	3,516,541	$	3,371,078	$	3,275,295	$	3,277,003	$	3,209,590

10

ENTERPRISE FINANCIAL SERVICES CORP

CONSOLIDATED FINANCIAL SUMMARY (unaudited) (continued)

	For the Quarter ended
(in thousands)	Sep 30, 2015			Jun 30, 2015			Mar 31, 2015			Dec 31, 2014			Sep 30, 2014
LOAN PORTFOLIO
Commercial and industrial	$	1,371,095		$	1,335,008		$	1,265,104		$	1,270,259		$	1,172,015
Commercial real estate	778,268			789,141			781,483			770,529			758,515
Construction real estate	152,979			150,740			138,924			144,773			123,888
Residential real estate	188,985			185,587			180,253			185,252			187,594
Consumer and other	110,829			82,079			69,795			63,103			52,893
Total portfolio loans	2,602,156			2,542,555			2,435,559			2,433,916			2,294,905
Purchase credit impaired loans	83,736			87,644			94,788			99,103			113,862
Total loans	$	2,685,892		$	2,630,199		$	2,530,347		$	2,533,019		$	2,408,767
DEPOSIT PORTFOLIO
Noninterest-bearing accounts	$	691,758		$	658,258		$	680,997		$	642,930		$	695,804
Interest-bearing transaction accounts	529,052			507,889			494,228			508,941			438,205
Money market and savings accounts	1,136,557			1,014,481			933,908			834,287			817,361
Certificates of deposit	456,596			510,930			565,498			505,352			558,394
Total deposit portfolio	$	2,813,963		$	2,691,558		$	2,674,631		$	2,491,510		$	2,509,764
AVERAGE BALANCES
Portfolio loans	$	2,540,948		$	2,482,291		$	2,425,962		$	2,368,475		$	2,280,377
Purchase credit impaired loans	85,155			92,168			97,201			104,732			115,709
Loans held for sale	4,255			6,605			3,560			3,703			5,400
Interest-earning assets	3,201,181			3,096,294			3,047,815			2,998,467			2,943,070
Total assets	3,416,716			3,310,578			3,268,369			3,234,485			3,180,359
Deposits	2,788,245			2,667,640			2,590,961			2,501,098			2,437,444
Shareholders' equity	338,368			330,999			321,772			315,557			306,307
Tangible common equity	304,583			296,931			287,423			280,920			271,370
YIELDS (fully tax equivalent)
Portfolio loans	4.16		%	4.17		%	4.15		%	4.19		%	4.22		%
Purchase credit impaired loans	19.41		%	18.33		%	20.85		%	26.47		%	14.67		%
Total loans	4.66		%	4.68		%	4.79		%	5.13		%	4.73		%
Securities	2.23		%	2.26		%	2.35		%	2.29		%	2.31		%
Interest-earning assets	4.17		%	4.24		%	4.33		%	4.60		%	4.24		%
Interest-bearing deposits	0.50		%	0.52		%	0.54		%	0.56		%	0.58		%
Total deposits	0.39		%	0.39		%	0.40		%	0.41		%	0.42		%
Subordinated debentures	2.19		%	2.18		%	2.15		%	2.14		%	2.14		%
Borrowed funds	0.28		%	0.29		%	0.36		%	0.77		%	0.76		%
Cost of paying liabilities	0.53		%	0.54		%	0.56		%	0.63		%	0.64		%
Net interest margin	3.77		%	3.85		%	3.92		%	4.13		%	3.75		%

11

ENTERPRISE FINANCIAL SERVICES CORP

CONSOLIDATED FINANCIAL SUMMARY (unaudited) (continued)

	For the Quarter ended
(in thousands, except per share data)	Sep 30, 2015			Jun 30, 2015			Mar 31, 2015			Dec 31, 2014			Sep 30, 2014
ASSET QUALITY1
Net charge-offs (recoveries)	$	113		$	672		$	1,478		$	582		$	(311	)
Nonperforming loans	9,123			17,498			15,143			22,244			18,212
Classified assets	62,679			61,722			63,001			77,898			81,382
Nonperforming loans to total loans	0.35		%	0.69		%	0.62		%	0.91		%	0.79		%
Nonperforming assets to total assets2	0.30		%	0.58		%	0.52		%	0.74		%	0.64		%
Allowance for loan losses to total loans	1.24		%	1.25		%	1.24		%	1.24		%	1.25		%
Allowance for loan losses to nonperforming loans	353.5		%	181.5		%	200.0		%	135.7		%	158.1		%
Net charge-offs (recoveries) to average loans (annualized)	0.02		%	0.11		%	0.25		%	0.10		%	(0.05		)%
WEALTH MANAGEMENT
Trust assets under management	$	848,515		$	889,616		$	894,456		$	865,414		$	857,071
Trust assets under administration	1,334,894			1,514,140			1,517,171			1,478,864			1,462,830
MARKET DATA
Book value per common share	$	17.21		$	16.67		$	16.36		$	15.94		$	15.61
Tangible book value per common share	$	15.53		$	14.96		$	14.64		$	14.20		$	13.85
Market value per share	$	25.17		$	22.77		$	20.66		$	19.73		$	16.72
Period end common shares outstanding	19,959			19,947			19,935			19,838			19,785
Average basic common shares	19,995			19,978			19,934			19,858			19,838
Average diluted common shares	20,261			20,168			20,157			20,140			19,980
CAPITAL
Total capital to risk-weighted assets3	12.56		%	12.68		%	12.88		%	13.40		%	13.61		%
Tier 1 capital to risk-weighted assets3	11.31		%	11.43		%	11.62		%	12.14		%	12.35		%
Common equity tier 1 capital to risk-weighted assets3	9.60		%	9.66		%	9.78		%	10.15		%	10.29		%
Tangible common equity to tangible assets	8.90		%	8.94		%	9.01		%	8.69		%	8.63		%
1 Portfolio loans only
2 Excludes Other real estate covered under FDIC loss share, except for inclusion in total assets.
3 Beginning with the quarter ended March 31, 2015, the implementation of revised regulatory capital guidelines under Basel III has resulted in differences in these items when compared to prior periods.

12

ENTERPRISE FINANCIAL SERVICES CORP

RECONCILIATIONS OF NON-GAAP FINANCIAL MEASURES

	For the Quarter ended															For the Nine Months ended
(in thousands)	Sep 30, 2015			Jun 30, 2015			Mar 31, 2015			Dec 31, 2014			Sep 30, 2014			Sep 30, 2015			Sep 30, 2014
CORE PERFORMANCE MEASURES
Net interest income	$	30,006		$	29,280		$	29,045		$	30,816		$	27,444		$	88,331		$	86,552
Less: Incremental accretion income	2,919			3,003			3,458			5,149			2,579			9,380			13,781
Core net interest income	27,087			26,277			25,587			25,667			24,865			78,951			72,771
Total noninterest income	4,729			5,806			3,583			4,852			4,452			14,118			11,779
Less: Change in FDIC loss share receivable	(1,241		)	(945		)	(2,264		)	(1,781		)	(2,374		)	(4,450		)	(7,526		)
Less (plus): Gain (loss) on sale of other real estate covered under FDIC loss share	31			10			(15		)	195			(45		)	26			250
Less: Gain on sale of investment securities	—			—			23			—			—			23			—
Less: Closing fee	—			—			—			—			945			—			945
Core noninterest income	5,939			6,741			5,839			6,438			5,926			18,519			18,110
Total core revenue	33,026			33,018			31,426			32,105			30,791			97,470			90,881
Provision for portfolio loans	599			2,150			1,580			1,968			66			4,329			2,441
Total noninterest expense	19,932			19,458			19,950			24,795			21,121			59,340			62,668
Less: FDIC clawback	298			50			412			141			1,028			760			1,060
Less: Other loss share expenses	287			378			470			544			746			1,135			2,409
Less: FHLB prepayment penalty	—			—			—			2,936			—			—			—
Less: Facilities disposal charge	—			—			—			1,004			—			—			—
Core noninterest expense	19,347			19,030			19,068			20,170			19,347			57,445			59,199
Core income before income tax expense	13,080			11,838			10,778			9,967			11,378			35,696			29,241
Core income tax expense	4,204			4,134			3,647			3,264			3,926			11,985			9,901
Core net income	$	8,876		$	7,704		$	7,131		$	6,703		$	7,452		$	23,711		$	19,340
Core diluted earnings per share	$	0.44		$	0.38		$	0.35		$	0.33		$	0.37		$	1.17		$	0.97
Core return on average assets	1.03		%	0.93		%	0.88		%	0.82		%	0.93		%	0.95		%	0.83		%
Core return on average common equity	10.41		%	9.34		%	8.99		%	8.43		%	9.65		%	9.59		%	8.70		%
Core return on average tangible common equity	11.56		%	10.41		%	10.06		%	9.47		%	10.89		%	10.70		%	9.88		%
Core efficiency ratio	58.58		%	57.64		%	60.67		%	62.83		%	62.83		%	58.94		%	65.14		%
NET INTEREST MARGIN TO CORE NET INTEREST MARGIN
Net interest income (fully tax equivalent)	$	30,437		$	29,691		$	29,467		$	31,223		$	27,843		$	89,595		$	87,779
Less: Incremental accretion income	2,919			3,003			3,458			5,149			2,579			9,380			13,781
Core net interest income (fully tax equivalent)	$	27,518		$	26,688		$	26,009		$	26,074		$	25,264		$	80,215		$	73,998
Average earning assets	$	3,201,181		$	3,096,294		$	3,047,815		$	2,998,467		$	2,943,070		$	3,115,658		$	2,896,202
Reported net interest margin (fully tax equivalent)	3.77		%	3.85		%	3.92		%	4.13		%	3.75		%	3.84		%	4.05		%
Core net interest margin (fully tax equivalent)	3.41		%	3.46		%	3.46		%	3.45		%	3.41		%	3.44		%	3.42		%

13

	At the Quarter ended
(in thousands)	Sep 30, 2015			Jun 30, 2015			Mar 31, 2015			Dec 31, 2014			Sep 30, 2014
COMMON EQUITY TIER 1 CAPITAL TO RISK-WEIGHTED ASSETS
Shareholders' equity	$	343,563		$	332,430		$	326,109		$	316,241		$	308,754
Less: Goodwill	30,334			30,334			30,334			30,334			30,334
Less: Intangible assets, net of deferred tax liabilities1	820			887			958			4,164			4,453
Less (Plus): Unrealized gains (losses)	2,973			1,249			3,379			1,681			(233		)
Plus: Qualifying trust preferred securities	55,100			55,100			55,100			55,100			55,100
Plus: Other	58			58			59			58			56
Total tier 1 capital	364,594			355,118			346,597			335,220			329,356
Less: Qualifying trust preferred securities	55,100			55,100			55,100			55,100			55,100
Less: Other1	23			23			23			—			—
Common equity tier 1 capital	$	309,471		$	299,995		$	291,474		$	280,120		$	274,256
Total risk-weighted assets	$	3,224,046		$	3,106,041		$	2,981,810		$	2,760,729		$	2,666,221
Common equity tier 1 capital to risk-weighted assets	9.60		%	9.66		%	9.78		%	10.15		%	10.29		%
SHAREHOLDERS' EQUITY TO TANGIBLE COMMON EQUITY AND TOTAL ASSETS TO TANGIBLE ASSETS
Shareholders' equity	$	343,563		$	332,430		$	326,109		$	316,241		$	308,754
Less: Goodwill	30,334			30,334			30,334			30,334			30,334
Less: Intangible assets	3,323			3,595			3,880			4,164			4,453
Tangible common equity	$	309,906		$	298,501		$	291,895		$	281,743		$	273,967
Total assets	$	3,516,541		$	3,371,078		$	3,275,295		$	3,277,003		$	3,209,590
Less: Goodwill	30,334			30,334			30,334			30,334			30,334
Less: Intangible assets	3,323			3,595			3,880			4,164			4,453
Tangible assets	$	3,482,884		$	3,337,149		$	3,241,081		$	3,242,505		$	3,174,803
Tangible common equity to tangible assets	8.90		%	8.94		%	9.01		%	8.69		%	8.63		%
1 Beginning with the quarter ended March 31, 2015, the implementation of revised regulatory capital guidelines under Basel III has resulted in differences in these items when compared to prior periods.

14