Item 3.02     Unregistered Sales of Equity Securities

On July 5, 2006 (the “Closing Date”), Enterprise Financial Services Corp, a Delaware corporation (“Enterprise”), completed its acquisition of NorthStar Bancshares, Inc., a Missouri corporation (“NorthStar”). NorthStar merged with and into Enterprise (the “Merger”), pursuant to an Amended and Restated Agreement and Plan of Merger, dated May 24, 2006, by and between Enterprise, NorthStar, NorthStar Bank, N.A., a national banking association and wholly owned subsidiary of NorthStar, and Leland M. Walker, as the Seller Representative (the “Merger Agreement”).

Pursuant to the Merger Agreement, shares of NorthStar common stock will be exchanged for cash and or cash and shares of Enterprise common stock. Those persons owning 1,000 or more shares of former NorthStar common stock on the Closing Date will receive, for each NorthStar share, approximately $5.90 in cash plus approximately 0.92 of a share of Enterprise common stock (less a portion of the share to be held in escrow). Persons owning less than 1,000 shares of former NorthStar common stock will receive a cash payment of approximately $29.48 for each NorthStar share (less a portion of cash to be held in escrow).

The 1,091,423 shares of Enterprise common stock issued or to be issued in connection with the Merger were not registered with the Securities and Exchange Commission. The issuance of these Enterprise shares is deemed a transaction not involving any public offering within the meaning of section 4(2) of the Securities Act of 1933 (the “Act”), and is exempt from registration under the provisions of Rule 506 of Regulation D of the Act. As mandated under Rule 506, no more than thirty-five (35) non-accredited investors will receive Enterprise common stock as a result of the Merger. Further, every recipient of Enterprise common stock pursuant to the Merger is an accredited investor, or, if not, is, (alone or together with his or her purchaser representative), sufficiently sophisticated in financial and business matters to be capable of evaluating the merits and risks of the investment in Enterprise. Enterprise represents that it has provided or made available all information required to be made available to non-accredited investors under Rule 502(b)(2) of Regulation D, as required under Rule 506(b)(1) of same.

The issuance and exchange of Enterprise common stock was undertaken without general solicitation or advertising. Each recipient of shares will represent to Enterprise that, among other things, such person is acquiring the shares for investment purposes and not with a view toward public distribution. As a result, the shares of Enterprise stock will be “restricted securities” and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements. Certificates evidencing the shares of Enterprise common stock received in the merger will contain a legend to that effect.

Item 7.01     Regulation FD Disclosure.

          On July 5, 2006, Enterprise issued a press release announcing the Merger. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

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