10/30/02 DRAFT

As filed with the Securities and Exchange Commission on November ___, 2002

Registration No. 333-


SECURITIES AND EXCHANGE
COMMISSION
Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT UNDER
THE SECURITIES ACT OF 1933


ENTERPRISE FINANCIAL SERVICES CORP
(Exact name of registrant as specified in its charter)

            Delaware                                   43-1706529
   (State or other jurisdiction            (I.R.S. Employer Identification  No.)
 of incorporation or organization)


150 North Meramec
Clayton, Missouri 63105
(Address of Principal Executive Offices)

INCENTIVE STOCK PURCHASE PLAN
(Full title of the plan)

James C. Wagner
Executive Vice President
Enterprise Financial Services Corp
150 North Meramec
Clayton, Missouri 63105
(Name and address of Agent for Service of Process)

(314) 725-5500
(Telephone Number, Including Area Code of Agent for Service)

Copy to:
Joseph S. von Kaenel, Esq.
Armstrong Teasdale LLP
One Metropolitan Square, Suite 2600
St. Louis, Missouri 63102-2740
(314) 621-5070

CALCULATION OF REGISTRATION FEE

================================================================================================================================
                                               Amount of         Proposed Maximum     Proposed Maximum
                                              Shares To Be      Offering Price Per    Aggregate Offering         Amount of
 Title of Securities To Be Registered      Registered (1)(2)          Share                Price            Registration Fee(2)
--------------------------------------------------------------------------------------------------------------------------------
Common Stock, par value $0.01 per share          278,885               $12.55            $3,500,007              $322.00
================================================================================================================================

(1) This registration statement also covers an indeterminate number of shares of Common Stock which may be issuable under the antidilution and other adjustment provisions of the plan pursuant to Rule 416(a) of the Securities Act of 1933, as amended (the "Securities Act").

(2) This amount reflects shares of Common Stock which are issuable under the Plan.

(3) Estimated in accordance with Rule 457(h) solely for purposes of calculating the registration fee and based upon the average of the high and low sale prices of the Common Stock on October 29, 2002.


INTRODUCTION

This Registration Statement on Form S-8 relates to shares of the Common Stock, par value $0.01 per share, of Enterprise Financial Services Corp (the "Company") to be offered pursuant to the Company's Incentive Stock Purchase Plan (the "Plan"). Pursuant to the Plan, the Company's bank subsidiary will from time to time purchase shares of the Company's Common Stock in the open market or other available sources for allocation to the accounts of eligible participants under the Plan using the proceeds of bank loans to participants under the Plan.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1. Plan Information.

The information called for in Item 1 of Form S-8 is currently included in the prospectus for the Plan and is not being filed with, or included in, this Form S-8 in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC").

Item 2. Registrant Information and Employee Plan Annual Information.

The Company will provide without charge to each person who has received a copy of any prospectus to which this Registration Statement relates, upon the written or oral request of that person, a copy of any or all the documents that have been or may be incorporated by reference into this Registration Statement, other than exhibits to those documents, unless the exhibits are incorporated by reference into those documents. Written requests for copies should be directed to the Company's principal executive offices at 150 North Meramec, Clayton, Missouri 63105, Attention: Secretary. Telephone requests for copies should be directed to the Secretary of the Company at (314) 725-5500.

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PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

This registration statement on Form S-8 relates to the registration of shares of Common Stock of the Company, $0.01 par value per share (the "Common Stock").

The following documents filed with the Commission by the Company (File No. 001-15373) are incorporated herein by reference and made a part hereof:

(a) The Company's Annual Report on Form 10-K for the year ended December 31, 2001.

(b) The Company's Quarterly Reports on Form 10-Q for the quarters ended March 31, 2002 and June 30, 2002, and the Company's Current Reports on Form 8-K filed April 30, 2002, July 10, 2002 and August 27, 2002.

All documents subsequently filed by the Company with the Commission pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than current reports furnished under Item 9 of Form 8-K) prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities covered by this Registration Statement have been sold or which deregisters all of the securities then remaining unsold, will be deemed to be incorporated by reference in this Registration Statement and to be a part of this document from the date of filing of such documents. Any statement contained in a document incorporated or deemed to be incorporated by reference in this document will be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained in this document or in any other subsequently filed document which also is or is deemed to be incorporated by reference in this document modifies or supersedes such statement. Any such statement so modified or superseded will not be deemed, except as so modified or amended, to constitute a part of this Registration Statement.

Item 4. Description of Securities.

The authorized capital stock of the Company consists of 20,000,000 shares of common stock, par value $.01 per share ("Common Stock"), of which 9,448,151 shares were outstanding as of October 22, 2002.

Holders of shares of Common Stock are entitled to receive dividends as may from time to time be declared by the Board of Directors of the Registrant out of funds legally available therefor. Holders of Common Stock are entitled to one vote per share on all matters on which the holders of Common Stock are entitled to vote and may cumulate their votes in any election of directors. Holders of Common Stock have no preemptive, conversion, redemption or sinking fund rights. In the event of a liquidation, dissolution or winding up of the Company, holders of

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Common Stock are entitled to share ratably in the assets of the Company, if any, remaining after payment of all debts and liabilities of the Company. The shares of Common Stock offered by the Company hereby will be fully paid and non-assessable when issued.

The Common Stock of the Company is not listed or traded on an exchange or in any established public trading market. The Company is aware of periodic trading activity in its stock which is reported in the Nasdaq Over-the-Counter Bulletin Board and there may be transactions from time to time at prices that are not known to the Company.

Item 5. Interests of Named Experts and Counsel.

Not applicable.

Item 6. Indemnification of Directors and Officers.

Section 102 of the Delaware General Corporation Law, or DGCL, as amended, allows a corporation to eliminate the personal liability of directors of a corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except where the director breached the duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of the DGCL or obtained an improper personal benefit.

Section 145 of the DGCL provides, among other things, that the Company may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding other than an action by or in the right of the Company, by reason of the fact that the person is or was a director, officer, agent or employee of the Company, or is or was serving at the Company's request as a director, officer, agent or employee of another corporation, partnership, joint venture, trust or other enterprise, against expenses, including attorneys' fees, judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding, if such person acting in good faith and in a manner he or she reasonably believed to be in the best interests, or not opposed to the best interests, of the Company, and with respect to any criminal action or proceeding had no reasonable cause to believe his or her conduct was unlawful. The power to indemnify applies to actions brought by or in the right of the Company as well, but only to the extent of defense expenses, reasonably incurred and not to any satisfaction of judgment or settlement of the claim itself, and with the further limitation that in such actions no indemnification shall be made in the event of any adjudication of liability to the Company, unless the court believes that in light of all the circumstances indemnification should apply. Furthermore, under the DGCL, if such person is successfully on the merits or otherwise in the defense of any action referred to above, or in the defense of any claim, issue or matter therein, such person shall be indemnified against expenses (including attorneys' fees) actually and reasonably incurred by such person in connection therewith.

Section 174 of the DGCL provides, among other things, that a director, who willfully or negligently approves of an unlawful payment of dividends or an unlawful purchase or redemption of stock, may be held liable for such actions. A director who was either absent when the unlawful actions were approved or dissented at the time, may avoid liability by causing his or

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her dissent to such actions to be entered in the books containing minutes of the meetings of the board of directors at the time such action occurred or immediately after such absent director receives notice of the unlawful acts.

As permitted by the DGCL, the Company's certificate of incorporation includes a provision to eliminate the personal liability of its directors for monetary damages for breach or alleged breach of their fiduciary duties as directors, subject to limited exceptions. The certificate of incorporation also provides that every person who is or was our director, officer, employee or agent or is or was a director, officer, trustee, employee or agent of any other enterprise, serving as such at the Company's request, shall be indemnified to the fullest extent permitted by law for all expenses and liabilities in connection with any proceeding involving such person in this capacity.

Item 7. Exemption from Registration Claimed.

Not applicable.

Item 8. Exhibits.

The exhibits to this Registration Statement are listed in the Exhibit Index which appears elsewhere herein and is hereby incorporated by reference.

Item 9. Undertakings.

(a) The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) to include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) to reflect in the prospectus any facts or event arising after the effective date of this registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement; and

(iii) to include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that the undertakings in paragraph (a)(1)(i) and
(a)(1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the Company pursuant to Section 13 or Section 15(d) of the Exchange Act, that are incorporated by reference in this registration statement.

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(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, duly authorized, as of October 31, 2002.

ENTERPRISE FINANCIAL SERVICES CORP

By:  /s/  James C. Wagner
     ---------------------------------
     James C. Wagner
     Executive Vice President

POWER OF ATTORNEY

We, the undersigned directors and officers of Enterprise Financial Services Corp (the "Company") and each of us, do hereby constitute and appoint James C. Wagner and Frank M. Sanfilippo, or either of them, our true and lawful attorneys-in-fact and agents, each with full power of substitution and resubstitution, to do any and all acts and things in our names and on our behalf in our capacities as directors and officers and to execute any and all instruments for us and in our names in the capacities indicated above, which said attorneys or agents, or either of them, may deem necessary or advisable to enable the Company to comply with the Securities Act of 1933, as amended, and any rules, regulations and amendments (including post-effective amendments) to the Registration Statement, including specifically but without limitation, power and authority to sign for us or any of us in our names in the capacities indicated below, any and all amendments (including post-effective amendments) to such Registration Statement; and we do hereby ratify and conform all that the said attorneys and agents, or their substitute or substitutes, or either of them, shall do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated:

Signatures                                  Title                                        Date
----------                                  -----                                        ----

     /s/ Paul J. McKee, Jr.                 Chairman of the Board and                    October 31, 2002
----------------------------------------
         Paul J. McKee, Jr.                 Director

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Signatures                                  Title                                        Date
----------                                  -----                                        ----
     /s/ Kevin C. Eichner                   President and Chief Executive               October 31, 2002
----------------------------------------
         Kevin C. Eichner                   Officer and Director


     /s/ Frank H. Sanfilippo                Chief Financial Officer (Principal          October 31, 2002
----------------------------------------
         Frank H. Sanfilippo                Financial and Accounting Officer)


________________________________________    Director                                    __________, 2002
         Paul R. Cahn


________________________________________    Director                                    __________, 2002
         Fred H. Eller


     /s/ Ronald E. Henges                   Director                                    October 31, 2002
----------------------------------------
         Ronald E. Henges


________________________________________    Director                                    __________, 2002
         Richard S. Masinton


________________________________________    Director                                    __________, 2002
         William B. Moskoff


     /s/ Birch M. Mullins                   Director                                    October 31, 2002
----------------------------------------
         Birch M. Mullins


________________________________________    Director                                    __________, 2002
         Ted A. Murray


     /s/ Stephen A. Oliver                  Director                                    October 31, 2002
----------------------------------------
         Stephen A. Oliver


     /s/ Robert E. Saur                     Director                                    October 31, 2002
----------------------------------------
         Robert E. Saur

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Signatures                                  Title                                        Date
----------                                  -----                                        ----
________________________________________    Director                                     __________, 2002
         Paul L. Vogel


     /s/ Henry D. Warshaw                   Director                                     October 31, 2002
----------------------------------------
         Henry D. Warshaw


     /s/ Jack L. Sutherland                 Director                                     October 31, 2002
----------------------------------------
         Jack L. Sutherland

________________________________________    Director                                     __________, 2002
         Ted C. Wetterau


     /s/ James L. Wilhite                   Director                                     October 31, 2002
----------------------------------------
         James L. Wilhite


     /s/ James A. Williams                  Director                                     October 31, 2002
----------------------------------------
         James A. Williams

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Exhibit Number     Description
--------------     -----------

4.1                Certificate of Incorporation of the Registrant, as amended, (incorporated herein by
                   reference to Exhibit 3.1 of the Registrant's Registration Statement on Form S-1 dated
                   December 19, 1996 (File No. 333-14737)).

4.2                Amendment to the Certificates of Incorporation of the Registrant (incorporated herein by
                   reference to Exhibit 4.2 to the Registrant's Registration Statement on Form S-8 dated
                   July 1, 1999 (File No. 333-82082)).

4.3                Amendment to the Certificates of Incorporation of the Registrant (incorporated herein by
                   reference to Exhibit 3.1 of the Registrant's Quarterly Report on Form 10-Q for the period
                   ending September 30, 1999).

4.4                Amendment to the Certificate of Incorporation of the Registrant (incorporated herein by
                   reference to Exhibit 99.2 to the Registrant's Current Report on Form 8-K filed on April
                   30, 2002).

4.5                Bylaws of the Registrant, as amended (incorporated herein by reference to Exhibit 3.4 of
                   the Registrant's Annual Report on Form 10-K for the period ending December 31, 1999).

4.6*               Enterprise Financial Services Corp Incentive Stock Purchase Plan

5.1*               Opinion of Armstrong Teasdale LLP

23.1*              Consent of KPMG LLP

23.3*              Consent of Armstrong Teasdale LLP (contained in Exhibit 5.1)

24.1*              Powers of Attorney (included in the signature pages of this Registration Statement)


* filed herewith

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Exhibit 4.6

ENTERPRISE FINANCIAL SERVICES CORP

INCENTIVE STOCK PURCHASE PLAN

I - INTRODUCTION

1. Purpose. The purpose of the Incentive Stock Purchase Plan (the "Plan") is to promote the interests of Enterprise Financial Services Corp (together with its subsidiaries, referred to as the "Company") and its stockholders by providing an opportunity for participating Key Employees, upon whose involvement, initiative and efforts the Company is largely dependent for the successful conduct of its business, to purchase Common Stock of the Company in a manner which will (a) provide an increased incentive for such Key Employees to exert their best efforts on behalf of the Company, (b) strengthen the ability of the Company to recruit and retain those persons possessing outstanding competence and the ability to contribute significantly to the Company's success,
(c) reward those Key Employees who have made significant contributions to the Company in the past, and (d) further identify the interests of such Key Employees with those of the Company and its stockholders by increasing the desire of such Key Employees to maximize the value of the Company. The Board establishes this Plan as strictly voluntary and part of the Enterprise Performance Recognition and Development Program. No positive or negative opinions will be formed on Key Employees based on participation. The Board recognizes that this Plan is not suitable for all Key Employees.

II. - DEFINITIONS

2.1 "Annual Group" means all of those Participants who have received Loan Commitments in a particular calendar year.

2.2 "Applicable Borrowing Rate" means, with respect to any Loan, the Prime Rate as published in the Wall Street Journal plus 1/2%, or any such higher rate as specified by the Board.

2.3 "Bank" means the Company's subsidiary, Enterprise Bank.

2.4 "Board" means the Board of Directors of the Company, provided that if any action taken by the Board relates to a Participant who is a director of the Company, the majority of the directors approving such action shall be disinterested directors.

2.5 "Common Stock" means shares of Common Stock of the Company.

2.6 "Confirmation" means the written statements that the Company promptly mails to a Participant's home address that (i) verify the terms of the Loan Agreement entered into between the Bank and a Participant, (ii) inform the Participant of Shares purchased on behalf of

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the Participant, and (iii) restate the account activity and Loan and Share balance as of August 15 of each year.

2.7 "Key Employee" means an employee of the Company so designated by the Board.

2.8 "Loan" means the loan made to a Participant pursuant to the Loan Agreement, the terms of which are described in Section 3.5 hereof. The aggregate principal balance of Loans outstanding under the Plan at any time to all Participants shall not exceed $3,500,000. The maximum loan amount available to a Participant shall be established by the Board at the time the Participant is designated a Key Employee.

2.9 "Loan Commitment" means the agreement of the Bank to make a Loan in a specified amount pursuant to an approved Loan Request Form.

2.10 "Loan Request Form" means the application which a Key Employee submits to the Board pursuant to which the Bank enters into an agreement with the Key Employee to loan him or her 100% of the Purchase Price of Common Stock (the "Loan Agreement"), and pursuant to which the Key Employee enters into an agreement with the Bank to pledge the purchased Shares to the Bank as collateral for the Loan (the "Pledge Agreement").

2.11 "Note(s)" mean promissory note(s) signed by the Participant which evidence the Loan entered into under the Loan Agreement.

2.12 "Participant" means any Key Employee of the Company who has submitted a Loan Request Form and has entered into a Loan Agreement and Pledge Agreement with the Bank.

2.13 "Purchase Price" means the price paid for the purchase of Shares including any applicable commission.

2.14 "Shares" means the shares of Common Stock purchased by a Participant pursuant to the Plan.

III. - OPERATION

3.1 Eligibility. The Board may from time to time during the term of the Plan identify Key Employees and designate them as such.

3.2 Offer. The Bank shall offer to loan 100% of the Purchase Price to all eligible Key Employees to finance their purchase of Common Stock. Such offer shall be subject to the terms provided herein.

3.3 Terms of Offer. Each offer to loan money to Key Employees to finance the purchase of Common Stock under this Plan shall be subject to the following:
(i) the Bank shall not make a loan for less than $25,000 to any Key Employee, and (ii) the Company shall not make a loan to a Key Employee who is an Executive Officer as defined by federal banking Regulation O in excess of 2.5% of the Bank's capital and surplus, but in no event in excess of $100,000 and only with prior Board approval.

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3.4 Acceptance. Key Employees may purchase Shares under the Plan by completing a Loan Request Form and submitting it to the Board for approval. After Board approval, the Bank and the Key Employee shall then enter into a Loan Agreement and Pledge Agreement, and the Participant shall sign the Note(s) evidencing the Loan. The Company may extend this offer to other employees deemed to be Key Employees in the future as determined by the Board. To the extent that the various agreements are not inconsistent with the terms and conditions of the Plan, the Company, the Bank and the Key Employee shall be bound by the terms of the various agreements, and the Key Employee shall become a Participant in the Plan.

3.5 Terms of Loan. The Bank's Loan to a Participant shall be for 100% of the Purchase Price of the Shares. Such Loan shall be evidenced by the Loan Agreement and the Notes, each of which shall contain the relevant terms and conditions set forth in this Section 3.5 and such other terms and conditions not inconsistent with the Plan, as the Board shall determine. The term of the Loan shall be for one year and subject to renewal on an annual basis. The Loan shall be secured by the pledge of the Shares as evidenced by the Pledge Agreement. The principal of the Loan shall bear interest at the Applicable Borrowing Rate, and the principal and accrued interest thereon shall be payable at the end of the term of the Loan. If the employment of the Participant is terminated for any reason, the principal, and accrued interest due on all outstanding Loans to the Participant under the Plan shall be subject to normal credit underwriting standards and subject to existing Bank loan policy. The Notes shall be subject to prepayment in whole or in part, at any time and from time to time, without premium or penalty. It shall be the Participant's responsibility to pay the interest due as governed by the terms of the Loan Agreement.

3.6 Security of Loan; Restrictions on Shares. The Participant shall be required to pledge the Shares to the Bank as collateral for the Loan pursuant to the Pledge Agreement. In addition, the Participant may not transfer or dispose of any Shares purchased under this Plan while participating in the Plan. Notwithstanding anything to the contrary herein, the Board may waive and may agree in advance to waive any contractual restrictions on the transfer of Shares subject to the Bank's lien under the Pledge Agreement.

3.7 Tax Withholding. The Company shall have the right to take such actions and to impose such conditions as it deems appropriate in order to collect from a Participant the amounts needed to satisfy the Company's income tax withholding obligations arising out of the Participant's participation in the Plan.

3.8 Rights as a Shareholder. Except as otherwise provided under the Plan, in the Loan Agreement, the Notes and the Pledge Agreement, a Participant who receives Shares pursuant to the Plan shall have the same rights and privileges as any other stockholder holding Common Stock, including, without limitation, the right to vote such Shares or other shares of stock and to receive distributions and dividends on such Shares.

3.9 Purchase and Allocation of Shares. The Bank's trust department shall purchase Shares on behalf of Participants in the open market or from other available sources. Purchased Shares shall be allocated first to the 2002 Annual Group until all Loan Commitments to Participants in that Annual Group have been fully drawn upon and then to the 2003 Annual Group until all Loan Commitments to Participants in that Annual Group have been fully drawn upon and then in a like manner to each subsequent Annual Group for each calendar year the Plan is in effect. At such time as all Loan Commitments to Participants in an Annual Group have

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been fully drawn upon, Shares purchased for such Annual Group shall be allocated among Participants in that Annual Group in proportion to the amounts of their respective Loans applied to such purchases based upon the average Purchase Price for such Shares.

3.10 Dividend, Voting and Other Rights with Respect to Unallocated Shares. Pending allocation of Shares to Participants, Participants in each Annual Group shall be entitled to receive dividends and to direct the voting or response to any consent solicitation with respect to any unallocated Shares in proportion to the amounts of their respective Loans as of the record date established for such dividends, voting or consent solicitation. For purposes of such voting or consent solicitation, each Participant shall within a reasonable time be provided with the proxy materials or other materials provided to stockholders with respect to such meeting or consent solicitation together with instructions for directing the voting or consent solicitation response with respect to such Shares. Any unallocated Shares for which instructions are not received within a reasonable time prior to any meeting or conclusion of any consent solicitation shall be voted in the same manner as the majority of Shares for which instructions are received. Participants may similarly direct the tender for purchase or acquisition of any unallocated Shares in which they have an interest in the event of an offer to purchase, exchange or otherwise acquire Shares is made to all stockholders of the Company, provided that Shares for which no instructions are received shall not be tendered.

IV. - GENERAL

4.1 Administration. The Plan shall be administered by the Board, or a committee designated by the Board, which shall have full and exclusive power to interpret the Plan, to grant waivers of Plan restrictions and to adopt such rules, regulations and guidelines for carrying out the Plan as it may deem necessary or proper, all of which powers shall be executed in the best interests of the Company and in keeping with the objectives of the Plan. The Company shall cause Confirmations to be sent to Participants on a periodic basis concerning their participation in the Plan.

4.2 Expenses. All expenses and costs in connection with the adoption and administration of the Plan shall be borne by the Company except to the extent that expenses are incurred in connection with collection of any Loan made to a Participant pursuant to the Plan, unless provided for otherwise in any of the various agreements hereunder.

4.3 No Prior Right or Offer. Except and until expressly granted pursuant to the Plan, nothing in the Plan shall be deemed to give any Key Employee, or his legal representatives or assigns or any other person or entity claiming under or through him, any contractual or other right to participate in the benefits of the Plan.

4.4 Action Taken in Good Faith, Indemnification. The Board may employ attorneys, consultants, accountants or other persons, and the Board, the Company and its officers and directors shall be entitled to rely upon the advice, opinions or valuations of any such persons. All action taken and all interpretations and determinations made by the Board in good faith shall be final and binding upon all Participants, all other employees of the Company, the Company and all other interested persons. No member of the Board nor any officer or employee of the Company acting on behalf of the Board, shall be personally liable for any action, determination or interpretation taken or made in good faith with respect to the Plan or purchase rights granted

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thereunder, and all members of the Board and each and any officer or employee of the Company acting on their behalf shall be fully indemnified and protected by the Company in respect of any such action, determination or interpretation.

4.5 Amendment and Termination of the Plan. The Board may amend the Plan at any time. The Plan may also be discontinued or terminated by the Board, in whole or in part, at any time. Notwithstanding the foregoing, no amendment, discontinuance, or termination of the Plan, without the consent of any persons affected thereby, shall alter or impair any rights or obligations created prior to such amendment, discontinuance, or termination.

4.6 No Agreement to Employ. Nothing in the Plan, Loan Request Form, Loan Agreement, Pledge Agreement or Notes shall confer upon any individual any right to continue in the employ of the Company for any specified period of time or interfere with the right of the Company to terminate such employment at any time.

4.7 Rights Personal to Key Employee. Any rights provided to a Participant under the Plan shall be personal to such Participant, shall not be transferable (except by will or pursuant to the laws of descent or distribution) and shall be exercisable, during his lifetime, only by him or her.

4.8 Governing Law. The Plan and all determinations made and actions taken pursuant hereto, to the extent not otherwise governed by the laws and regulations of the United States, shall be governed by the law of the State of Missouri and construed accordingly.

4.9 Regulation U. This Plan is based upon the Common Stock not being subject to the provisions of 12 CFR Part 221, Regulation U, Margin Stock. If it is determined that the Shares meet the definition of margin stock as defined in Regulation U, the Board shall amend or terminate this Plan to comply with Regulation U's requirements.

4.10 Term of Plan. The Board on April 17, 2002, adopted the Plan. Shares of Common Stock may be purchased under the Plan until the Participant's account is fully funded. The Plan shall cease on December 31, 2005, but shall continue past such time until all Loans have been repaid by Participants.

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Exhibit 5.1

[Armstrong Teasdale LLP Letterhead]

October 31, 2002

Enterprise Financial Services Corp
150 North Meramec
Clayton, Missouri 63105

Ladies and Gentlemen:

We have acted as counsel to Enterprise Financial Services Corp (the "Company") in connection with the preparation and filing with the Securities and Exchange Commission of the registration statement of the Company on Form S-8 under the Securities Act of 1933, as amended (the "Registration Statement"), with respect to 278,885 shares of common stock, par value $0.01, of the Company (the "Shares") issuable pursuant to the Enterprise Financial Services Corp Incentive Stock Purchase Plan (the "Plan"). Capitalized terms defined in the Registration Statement and used (but not otherwise defined) herein are used herein as so defined.

In so acting, we have examined originals or copies (certified or otherwise identified to our satisfaction) of the Registration Statement, the Plan and such corporate records, agreements, documents and other instruments, and such certificates or comparable documents or public officials and of officers and representatives of the Company, and have made such inquiries of such officers and representatives, as we have deemed relevant and necessary as a basis for the opinions hereinafter set forth.

In such examination, we have assumed the genuineness of all signatures, the legal capacity of all natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as certified, conformed or photostatic copies and the authenticity of the originals of such latter documents. As to all questions of fact material to these opinions that have not been independently established, we have relied upon certificates or comparable documents of officers and representatives of the Company.

Based on the foregoing, and subject to the qualifications stated herein, we are of the opinion that the Shares to be issued pursuant to the terms of the Plan have been duly authorized and, when issued as contemplated by the Plan, will be validly issued, fully paid and nonassessable.

We hereby consent to the use of this letter as an exhibit to the Registration Statement.

Very truly yours,

/s/ Armstrong Teasdale LLP


Exhibit 23.1

Independent Auditors' Consent

The Board of Directors
Enterprise Financial Services Corp:

We consent to the incorporation by reference in the registration statement on Form S-8 of Enterprise Financial Services Corp (formerly Enterbank Holdings, Inc.) of our report dated March 27, 2002, with respect to the consolidated balance sheets of Enterprise Financial Services Corp as of December 31, 2001 and 2000, and the related consolidated statements of operations, shareholders' equity, cash flows and comprehensive income for each of the years in the three year period ended December 31, 2001, which report appears in the December 31, 2001 Annual Report on Form 10-K of Enterprise Financial Services Corp.

/s/ KPMG LLP

St. Louis, Missouri
October 30, 2002