EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-8 of our report dated February 23, 2018, relating to the financial statements of Enterprise Financial Services Corp and subsidiaries, and the effectiveness of Enterprise Financial Services Corp and subsidiaries' internal control over financial reporting, appearing in the Annual Report on Form 10-K of Enterprise Financial Service Corporation for the year ended December 31, 2017.

/s/ Deloitte & Touche LLP

St. Louis, Missouri

July 27, 2018