Exhibit 32.1

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Enterprise Financial Services Corp
(the "Company") on Form 10-Q for the period ending June 30, 2003 as filed with
the Securities and Exchange Commission (the "Report"), I, Kevin C. Eichner,
Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section
1350, as enacted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002,
that:

The Report fully complies with the requirements of Section 13(a) or 15(d) of the
Securities Exchange Act of 1934; and the information contained in the Report
fairly presents, in all material respects, the financial condition and results
of operations of the Company.


/s/ Kevin C. Eichner
- ------------------------
Kevin C. Eichner
Chief Executive Officer
August 14, 2003


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