Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

     On December 12, 2008, Enterprise Financial Services Corp, a Delaware corporation (“EFSC”), through a newly formed trust subsidiary EFSC Capital Trust VIII, a Delaware statutory trust (the “Trust”), issued and sold $25,000,000 of preferred securities in the Trust (the “Trust Preferred Securities”) to a group of investors led by an east coast investment company manager. The Trust used the proceeds generated from the issuance and sale of the Trust Preferred Securities to purchase 9.00% Junior Subordinated Deferrable Interest Debentures maturing in 2038 from EFSC in the aggregate principal amount of $25,000,000 (the “Debentures”) pursuant to the terms of the Indenture dated December 12, 2008 (the “Indenture”) by and between EFSC and Wilmington Trust Company, a Delaware banking corporation (“Wilmington”), as trustee of the Trust. A copy of the Indenture is filed as Exhibit 4.1 to this Form 8-K, which is incorporated herein by this reference, and the summary set forth below is qualified in its entirety by reference to the Indenture. EFSC relied upon an exemption from registration set forth in Section 4(2) of the Securities Act of 1933, as amended (the “1933 Act”), in connection with the offering and issuance of the Trust Preferred Securities.

     The Debentures are the sole assets of the Trust and are senior to common stock, but are subordinate to the prior payment of any other indebtedness of EFSC that, by its terms, is not similarly subordinated. The Debentures mature on December 15, 2038 (the “Maturity Date”). The Trust Preferred Securities have no stated maturity date, but as a practical matter, will receive a final payment of their outstanding liquidation amount plus accrued but unpaid interest, upon payment to the Trust by EFSC of the Debentures at their maturity.

     The Debentures will bear interest at 9.00%, due and payable in arrears on March 15, June 15, September 15 and December 15 of each year (the “Interest Payment Dates”) until the Maturity Date. The Trust Preferred Securities carry a cumulative preferred dividend payable on the same payment dates and in the same amount as, and only to the extent that, EFSC pays interest to the Trust on an equivalent principal amount of the Debentures.

     Subject to certain regulatory approvals, the Debentures and the Trust Preferred Securities are each callable by EFSC or the Trust, respectively and as applicable, at their option after December 15, 2013, and sooner upon the occurrence of certain events such as a change in the regulatory capital treatment of the Trust Preferred Securities, the Trust being deemed an investment company and/or the occurrence of certain adverse tax events. Until June 12, 2009, holders of the Trust Preferred Securities will also have the right to participate in any future equity offering that EFSC proposes to engage in at the same percentage that such holders participated in the issuance of the Trust Preferred Securities.

     The terms of the Trust Preferred Securities are governed by an Amended and Restated Declaration of Trust, dated December 12, 2008, by and among EFSC, as sponsor, Wilmington, as Delaware trustee, Wilmington, as institutional trustee, and each of the Administrators named therein (the “Amended and Restated Declaration”). A copy of the Amended and Restated Declaration is filed as Exhibit 4.2 to this Form 8-K, which is incorporated herein by this reference, and the summary set forth above is qualified in its entirety by reference to the Amended and Restated Declaration.