Exhibit 4.9.4
                 Trust Preferred Securities Guarantee Agreement

                 TRUST PREFERRED SECURITIES GUARANTEE AGREEMENT

                                 BY AND BETWEEN

                     Enterprise Financial Services Corp. AND

                     Wells Fargo Bank, National Association

                          EFFECTIVE AS OF June 27, 2002





                                TABLE OF CONTENTS



                                                                                                     Page
                                                                                                
ARTICLE I        DEFINITIONS AND INTERPRETATION........................................................1
    Section 1.1      Definitions and Interpretation....................................................1
ARTICLE II       TRUST INDENTURE ACT...................................................................5
    Section 2.1      Indenture Act; Application........................................................5
    Section 2.2      Lists of Holders of Securities....................................................5
    Section 2.3      Reports by the Trust Preferred Guarantee Trustee..................................5
    Section 2.4      Reports to Trust Preferred Guarantee Trustee......................................6
    Section 2.5      Evidence of Compliance with Conditions Precedent..................................6
    Section 2.6      Event of Default; Waiver..........................................................6
    Section 2.7      Event of Default; Notice..........................................................6
    Section 2.8      Conflicting Interests.............................................................7
ARTICLE III      POWERS, DUTIES AND RIGHTS OF TRUST PREFERRED GUARANTEE TRUSTEE........................7
    Section 3.1      Powers and Duties of the Trust Preferred Guarantee Trustee........................7
    Section 3.2      Certain Rights of Trust Preferred Guarantee Trustee...............................9
    Section 3.3      Not Responsible for Recitals or Issuance of Guarantee............................11
ARTICLE IV       TRUST PREFERRED GUARANTEE TRUSTEE....................................................11
    Section 4.1      Trust Preferred Guarantee Trustee; Eligibility...................................11
    Section 4.2      Appointment, Removal and Resignation of Trust Preferred Guarantee Trustees.......12
ARTICLE V        GUARANTEE............................................................................13
    Section 5.1      Guarantee........................................................................13
    Section 5.2      Waiver of Notice and Demand......................................................13
    Section 5.3      Obligations not Affected.........................................................13
    Section 5.4      Rights of Holders................................................................14
    Section 5.5      Guarantee of Payment.............................................................14
    Section 5.6      Subrogation......................................................................14
    Section 5.7      Independent Obligations..........................................................15


                                      -i-



                                TABLE OF CONTENTS
                                   (continued)


                                                                                                     Page
                                                                                                
ARTICLE VI       LIMITATION OF TRANSACTIONS; SUBORDINATION............................................15
    Section 6.1      Limitation of Transactions.......................................................15
    Section 6.2      Ranking..........................................................................16
ARTICLE VII      TERMINATION..........................................................................16
    Section 7.1      Termination......................................................................16
ARTICLE VIII     INDEMNIFICATION......................................................................16
    Section 8.1      Exculpation......................................................................16
    Section 8.2      Indemnification..................................................................17
ARTICLE IX       MISCELLANEOUS........................................................................17
    Section 9.1      Successors and Assigns...........................................................17
    Section 9.2      Amendments.......................................................................17
    Section 9.3      Notices..........................................................................18
    Section 9.4      Benefit..........................................................................18
    Section 9.5      Governing Law....................................................................18


                                      -ii-





                 TRUST PREFERRED SECURITIES GUARANTEE AGREEMENT

     THIS TRUST PREFERRED SECURITIES GUARANTEE AGREEMENT (this "Trust Preferred
Securities Guarantee"), effective as of June 27, 2002, is executed and delivered
by Enterprise Financial Services Corp., a Delaware corporation (the
"Guarantor"), and Wells Fargo Bank, National Association, as trustee (the "Trust
Preferred Guarantee Trustee"), for the benefit of the Holders (as defined
herein) from time to time of the Trust Preferred Securities (as defined herein)
of EFSC Capital Trust I, a Delaware statutory business trust (the "Trust").

                                    RECITALS

     WHEREAS, pursuant to an Amended and Restated Trust Agreement (the "Trust
Agreement"), effective as of June 27, 2002, among the trustees of the Trust
named therein, the Guarantor, as depositor, and the holders from time to time of
undivided beneficial interests in the assets of the Trust, the Trust is issuing
on the date hereof up to Four Thousand (4,000) preferred securities, having an
aggregate liquidation amount of Four Million Dollars ($4,000,000), and such
preferred securities being designated the Floating Rate Cumulative Trust
Preferred Securities (the "Trust Preferred Securities");

     WHEREAS, as incentive for the Holders to purchase the Trust Preferred
Securities, the Guarantor desires irrevocably and unconditionally to agree, to
the extent set forth in this Trust Preferred Securities Guarantee, to pay to the
Holders of the Trust Preferred Securities the Guarantee Payments (as defined
herein) and to make certain other payments on the terms and conditions set forth
herein.

     NOW, THEREFORE, in consideration of the purchase by each Holder of Trust
Preferred Securities, which purchase the Guarantor hereby agrees shall benefit
the Guarantor, the Guarantor executes and delivers this Trust Preferred
Securities Guarantee for the benefit of the Holders.

                                   ARTICLE I

                         DEFINITIONS AND INTERPRETATION

     Section 1.1 Definitions and Interpretation.

          In this Trust Preferred Securities Guarantee, unless the context
     otherwise requires:

          (a) capitalized terms used herein but not defined in the preamble
     above have the respective meanings assigned to them in this Section 1.1;

          (b) terms defined in the Trust Agreement as of the date of execution
     of this Trust Preferred Securities Guarantee have the same meaning when
     used in this Trust Preferred Securities Guarantee, unless otherwise defined
     in this Trust Preferred Securities Guarantee;

          (c) a term defined anywhere in this Trust Preferred Securities
     Guarantee has the same meaning throughout;



          (d) all references to "the Trust Preferred Securities Guarantee" or
     "this Trust Preferred Securities Guarantee" are to this Trust Preferred
     Securities Guarantee as modified, supplemented or amended from time to
     time;

          (e) all references in this Trust Preferred Securities Guarantee to
     Articles and Sections are to Articles and Sections of this Trust Preferred
     Securities Guarantee, unless otherwise specified;

          (f) a term defined in the Trust Indenture Act (as defined below) has
     the same meaning when used in this Trust Preferred Securities Guarantee,
     unless otherwise defined in this Trust Preferred Securities Guarantee or
     unless the context otherwise requires; and

          (g) a reference to the singular includes the plural and vice versa.

     "Affiliate" has the same meaning as given to that term in Rule 405 of the
Securities Act of 1933, as amended, or any successor rule thereunder.

     "Business Day" means any day other than a Saturday, Sunday, a day on which
federal or state banking institutions in Clayton, Missouri, Wilmington, Delaware
or Minneapolis, Minnesota are authorized or required by law, executive order or
regulation to close or a day on which the Corporate Trust Office of the Trust
Preferred Guarantee Trustee is closed for business.

     "Corporate Trust Office" means the office of the Trust Preferred Guarantee
Trustee at which the corporate trust business of the Trust Preferred Guarantee
Trustee shall, at any particular time, be principally administered, which office
at the date of execution of this Agreement is located at 919 Market Street,
Suite 700

Wilmington, Delaware 19801 , Attention: Corporate Trust Administration.

     "Covered Person" means any Holder or beneficial owner of Trust Preferred
Securities.

     "Debentures" means the Floating Rate Junior Subordinated Deferrable
Interest Debentures due June 30, 2032, of the Debenture Issuer held by the
Property Trustee (as defined in the Trust Agreement) on behalf of the Trust.

     "Debenture Issuer" means Enterprise Financial Services Corp., issuer of the
Debentures under the Indenture.

     "Event of Default" means a default by the Guarantor on any of its payment
or other obligations under this Trust Preferred Securities Guarantee.

     "Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Trust Preferred Securities, to the extent not
paid or made by the Trust: (i) any accumulated and unpaid Distributions (as
defined in the Trust Agreement) that are required to be paid on such Trust
Preferred Securities, to the extent the Trust shall have funds legally available
therefor, (ii) the redemption price, including all accumulated and unpaid
Distributions to the date of redemption (the "Redemption Price"), to the extent
the Trust has funds legally available therefor, with respect to any Trust
Preferred Securities called for

                                      -2-



redemption by the Trust, and (iii) upon a voluntary or involuntary dissolution,
winding-up or termination of the Trust (other than in connection with the
distribution of Debentures to the Holders in exchange for Trust Preferred
Securities as provided in the Trust Agreement), the lesser of (a) the aggregate
of the liquidation amount and all accumulated and unpaid Distributions on the
Trust Preferred Securities to the date of payment, to the extent the Trust shall
have funds legally available therefor, and (b) the amount of assets of the Trust
remaining legally available for distribution to Holders in liquidation of the
Trust (the "Liquidation Distribution").

     "Holder" shall mean any holder, as registered on the books and records of
the Trust, of any Trust Preferred Securities; provided, however, that, in
determining whether the holders of the requisite percentage of Trust Preferred
Securities have given any request, notice, consent or waiver hereunder, "Holder"
shall not include the Guarantor or the Trust Preferred Guarantee Trustee;
provided, further, that the Trust Preferred Guarantee Trustee shall be protected
in acting on any such request, notice, consent or waiver unless a Responsible
Officer of the Trust Preferred Guarantee Trustee shall have actual knowledge
that the holder of such Trust Preferred Securities is the Guarantor.

     "Indemnified Person" means the Trust Preferred Guarantee Trustee, any
Affiliate of the Trust Preferred Guarantee Trustee, or any officers, directors,
shareholders, members, partners, employees, representatives, nominees,
custodians or agents of the Trust Preferred Guarantee Trustee.

     "Indenture" means the Indenture effective as of June 27, 2002, among the
Debenture Issuer and Wells Fargo Bank, National Association, as trustee, and any
indenture supplemental thereto pursuant to which certain subordinated debt
securities of the Debenture Issuer are to be issued to the Property Trustee on
behalf of the Trust.

     "Liquidation Amount" means the stated value of $1,000 per Trust Preferred
Security.

     "Liquidation Distribution" has the meaning provided therefor in the
definition of Guarantee Payments.

     "List of Holders" has the meaning provided therefor in Section 2.2(a)
hereof.

     "Majority in Liquidation Amount of the Trust Preferred Securities" means
the Holders of more than 50% of the Liquidation Amount of the Outstanding (as
defined in the Trust Agreement) Trust Preferred Securities.

     "Officers' Certificate" means, with respect to any Person, a certificate
signed by two authorized officers of such Person, at least one of whom shall be
the principal executive officer, principal financial officer, principal
accounting officer, treasurer or any vice president of such Person. Any
Officers' Certificate delivered with respect to compliance with a condition or
covenant provided for in this Trust Preferred Securities Guarantee shall
include:

          (a) a statement that each officer signing the Officers' Certificate
     has read the covenant or condition and the definition relating thereto;

                                      -3-



          (b) a brief statement of the nature and scope of the examination or
     investigation undertaken by each officer in rendering the Officers'
     Certificate;

          (c) a statement that each such officer has made such examination or
     investigation as, in such officer's opinion, is necessary to enable such
     officer to express an informed opinion as to whether or not such covenant
     or condition has been complied with; and

          (d) a statement as to whether, in the opinion of each such officer,
     such condition or covenant has been complied with.

     "Person" means a legal person, including any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof, or any other entity of whatever nature.

     "Redemption Price" has the meaning provided therefor in the definition of
Guarantee Payments.

     "Responsible Officer" means, with respect to the Trust Preferred Guarantee
Trustee, any officer within the Corporate Trust Office of the Trust Preferred
Guarantee Trustee with direct responsibility for the administration of this
Trust Preferred Securities Guarantee, including any vice-president, any
assistant vice-president, any assistant secretary or other officer or assistant
officer of the Trust Preferred Guarantee Trustee customarily performing
functions similar to those performed by any of the Persons who at the time shall
be such officers, or to whom a corporate trust matter is referred because of
that officer's knowledge of and familiarity with the particular subject.

     "Securities Register" and "Securities Registrar" have the meanings provided
for each in the Trust Agreement.

     "Successor Trust Preferred Guarantee Trustee" means a successor Trust
Preferred Guarantee Trustee possessing the qualifications to act as Trust
Preferred Guarantee Trustee under Section 4.1 hereof.

     "Trust Agreement" has the meaning provided therefor in the Recitals hereof.

     "Trust Indenture Act" means the Trust Indenture Act of 1939 or any
successor statute thereto, in each case as amended from time to time.

     "Trust Preferred Guarantee Trustee" means Wells Fargo Bank, National
Association, in its capacity as trustee under this Trust Preferred Securities
Guarantee until a Successor Trust Preferred Guarantee Trustee has been appointed
and has accepted such appointment pursuant to the terms of this Trust Preferred
Securities Guarantee and thereafter means each such Successor Trust Preferred
Guarantee Trustee.

                                      -4-



                                   ARTICLE II

                               TRUST INDENTURE ACT

     Section 2.1 Indenture Act; Application.

          (a) Unless and until the Indenture is required to be qualified under
     the Trust Indenture Act so that the provisions thereof are applicable (i)
     the provisions of the Trust Indenture Act do not apply to this Trust
     Preferred Securities Guarantee and are not given effect; and (ii)
     notwithstanding any other provision set forth herein, the Trust Preferred
     Guarantee Trustee shall not be liable for its own simple negligence, but
     shall only be liable for its own gross negligence.

          (b) If and to the extent that any provision of this Trust Preferred
     Securities Guarantee limits, qualifies or conflicts with the duties imposed
     by Section 310 to 317, inclusive, of the Trust Indenture Act, and the
     Indenture is then required to be qualified under the Trust Indenture Act so
     that the provisions thereof are applicable, such imposed duties shall
     control.

     Section 2.2 Lists of Holders of Securities.

          (a) In the event the Trust Preferred Guarantee Trustee is not also the
     Securities Registrar, the Guarantor shall provide the Trust Preferred
     Guarantee Trustee with a list, in such form as the Trust Preferred
     Guarantee Trustee may reasonably require, of the names and addresses of the
     Holders ("List of Holders") as of the date (i) within five (5) Business
     Days after March 15, June 15, September 15 and December 15, and (ii) at any
     other time within 30 days of receipt by the Guarantor of a written request
     for a List of Holders as of a date no more than 15 days before such List of
     Holders is given to the Trust Preferred Guarantee Trustee; provided, that
     the Guarantor shall not be obligated to provide such List of Holders at any
     time the List of Holders does not differ from the most recent List of
     Holders given to the Trust Preferred Guarantee Trustee by the Guarantor.
     The Trust Preferred Guarantee Trustee may destroy any List of Holders
     previously given to it on receipt of a new List of Holders.

          (b) If applicable, the Trust Preferred Guarantee Trustee shall comply
     with its obligations under Sections 311(a), 311(b) and Section 312(b) of
     the Trust Indenture Act.

     Section 2.3 Reports by the Trust Preferred Guarantee Trustee.

          (a) On or before July 15 in each year in which any of the Trust
     Preferred Securities are Outstanding, the Trust Preferred Guarantee Trustee
     shall transmit by mail, first class postage prepaid, to the Holders, as
     their names and addresses appear upon the Securities Register, a brief
     report dated as of the preceding May 15, if and to the extent required
     under Section 313(a) of the Trust Indenture Act, if applicable (it being
     understood that no such report shall be required if none of the events set
     forth in Section 313(a) of the Trust Indenture Act has occurred during the
     period to which such report would relate).

                                      -5-



          (b) The Trust Preferred Guarantee shall comply with Sections 313(b)
     and 313(c) of the Trust Indenture Act, if applicable.

          (c) A copy of each such report shall, at the time of such transmission
     to the Holders, be filed by the Trust Preferred Guarantee Trustee with the
     Company, with each stock exchange or applicable self-regulatory
     organization upon which any Trust Preferred Securities are listed (if so
     listed) and also with the Securities and Exchange Commission. The Company
     agrees to notify the Trust Preferred Guarantee Trustee when any Trust
     Preferred Securities become listed on any stock exchange or other
     applicable self-regulatory organization.

     Section 2.4 Reports to Trust Preferred Guarantee Trustee.

     If applicable, the Guarantor shall provide to the Trust Preferred Guarantee
Trustee such documents, reports and information as required by Section 314 (if
any) and the compliance certificate required by Section 314 of the Trust
Indenture Act in the form, in the manner and at the times required by Section
314 of the Trust Indenture Act.

     Section 2.5 Evidence of Compliance with Conditions Precedent.

     If applicable, the Guarantor shall provide to the Trust Preferred Guarantee
Trustee such evidence of compliance with any conditions precedent provided for
in this Trust Preferred Securities Guarantee that relate to any of the matters
set forth in Section 314(c) of the Trust Indenture Act. Any certificate or
opinion required to be given by an officer pursuant to Section 314(c)(1) of the
Trust Indenture Act may be given in the form of an Officers' Certificate.

     Section 2.6 Event of Default; Waiver.

     The Holders of a Majority in Liquidation Amount of Trust Preferred
Securities may, by vote, on behalf of the Holders of all of the Trust Preferred
Securities, waive any past Event of Default and its consequences. Upon such
waiver, any such Event of Default shall cease to exist, and any Event of Default
arising therefrom shall be deemed to have been cured, for every purpose of this
Trust Preferred Securities Guarantee, but no such waiver shall extend to any
subsequent or other default or Event of Default or impair any right consequent
thereon.

     Section 2.7 Event of Default; Notice.

     The Trust Preferred Guarantee Trustee shall, within ninety (90) days after
the occurrence of an Event of Default, transmit by mail, first class postage
prepaid, to the Holders of the Trust Preferred Securities, notices of all Events
of Default actually known to a Responsible Officer of the Trust Preferred
Guarantee Trustee, unless such defaults have been cured before the giving of
such notice; provided, that, except in the case of a default by Guarantor on any
of its payment obligations, the Trust Preferred Guarantee Trustee shall be
protected in withholding such notice if and so long as the board of directors,
the executive committee or a trust committee of the directors and/or Responsible
Officers of the Trust Preferred Guarantee Trustee in good faith determines that
the withholding of such notice is in the interests of the Holders of the Trust
Preferred Securities.

                                      -6-



     The Trust Preferred Guarantee Trustee shall not be deemed to have knowledge
of any Event of Default unless the Trust Preferred Guarantee Trustee shall have
received written notice of such Event of Default, or a Responsible Officer of
the Trust Preferred Guarantee Trustee charged with the administration of the
Trust Agreement shall have obtained actual knowledge of such Event of Default.

     Section 2.8 Conflicting Interests.

     The Trust Agreement shall be deemed to be specifically described in this
Trust Preferred Securities Guarantee for the purposes of clause (i) of the first
proviso contained in Section 310(b) of the Trust Indenture Act, if applicable.

                                  ARTICLE III

         POWERS, DUTIES AND RIGHTS OF TRUST PREFERRED GUARANTEE TRUSTEE

     Section 3.1 Powers and Duties of the Trust Preferred Guarantee Trustee.

          (a) This Trust Preferred Securities Guarantee shall be held by the
     Trust Preferred Guarantee Trustee for the benefit of the Holders of the
     Trust Preferred Securities, and the Trust Preferred Guarantee Trustee shall
     not transfer this Trust Preferred Securities Guarantee to any Person except
     a Holder of Trust Preferred Securities exercising his or her rights
     pursuant to Section 5.4(b) hereof or to a Successor Trust Preferred
     Guarantee Trustee on acceptance by such Successor Trust Preferred Guarantee
     Trustee of its appointment to act as Successor Trust Preferred Guarantee
     Trustee. The right, title and interest of the Trust Preferred Guarantee
     Trustee shall automatically vest in any Successor Trust Preferred Guarantee
     Trustee, and such vesting and cessation of title shall be effective whether
     or not conveyancing documents have been executed and delivered pursuant to
     the appointment of such Successor Trust Preferred Guarantee Trustee.

          (b) If an Event of Default actually known to a Responsible Officer of
     the Trust Preferred Guarantee Trustee has occurred and is continuing, the
     Trust Preferred Guarantee Trustee shall enforce this Trust Preferred
     Securities Guarantee for the benefit of the Holders of the Trust Preferred
     Securities.

          (c) The Trust Preferred Guarantee Trustee, before the occurrence of
     any Event of Default and after the curing of all Events of Default that may
     have occurred, shall undertake to perform only such duties as are
     specifically set forth in this Trust Preferred Securities Guarantee. In
     case an Event of Default has occurred (that has not been cured or waived
     pursuant to Section 2.6 hereof) and is actually known to a Responsible
     Officer of the Trust Preferred Guarantee Trustee, the Trust Preferred
     Guarantee Trustee shall exercise such of the rights and powers vested in it
     by this Trust Preferred Securities Guarantee, and use the same degree of
     care and skill in its exercise thereof, as a prudent person would exercise
     or use under the circumstances in the conduct of his or her own affairs. No
     implied covenants shall be read into the Trust Preferred Securities
     Guarantee against the Trust Preferred Guarantee Trustee.

                                      -7-



          (d) No provision of this Trust Preferred Securities Guarantee shall be
     construed to relieve the Trust Preferred Guarantee Trustee from liability
     for its own negligent action, its own negligent failure to act, or its own
     willful misconduct, except that:

          (i)  prior to the occurrence of any Event of Default and after the
               curing or waiving of all such Events of Default that may have
               occurred:

               (A)  the duties and obligations of the Trust Preferred Guarantee
                    Trustee shall be determined solely by the express provisions
                    of this Trust Preferred Securities Guarantee, and the Trust
                    Preferred Guarantee Trustee shall not be liable except for
                    the performance of such duties and obligations as are
                    specifically set forth in this Trust Preferred Securities
                    Guarantee, and no implied covenants or obligations shall be
                    read into this Trust Preferred Securities Guarantee against
                    the Trust Preferred Guarantee Trustee; and

               (B)  in the absence of bad faith on the part of the Trust
                    Preferred Guarantee Trustee, the Trust Preferred Guarantee
                    Trustee may conclusively rely, as to the truth of the
                    statements and the correctness of the opinions expressed
                    therein, upon any certificates or opinions furnished to the
                    Trust Preferred Guarantee Trustee and conforming to the
                    requirements of this Trust Preferred Securities Guarantee;
                    but in the case of any such certificates or opinions that by
                    any provision hereof are specifically required to be
                    furnished to the Trust Preferred Guarantee Trustee, the
                    Trust Preferred Guarantee Trustee shall be under a duty to
                    examine the same to determine in good faith whether or not
                    they conform to the requirements of this Trust Preferred
                    Securities Guarantee;

          (ii) the Trust Preferred Guarantee Trustee shall not be liable for any
               error of judgment made in good faith by a Responsible Officer of
               the Trust Preferred Guarantee Trustee, unless it shall be proved
               that the Trust Preferred Guarantee Trustee was negligent in
               ascertaining the pertinent facts upon which such judgment was
               made;

          (iii) the Trust Preferred Guarantee Trustee shall not be liable with
               respect to any action taken or omitted to be taken by it in good
               faith in accordance with the direction of the Holders of not less
               than a Majority in Liquidation Amount of the Trust Preferred
               Securities relating to the time, method and place of conducting
               any proceeding for any remedy available to the Trust Preferred
               Guarantee Trustee, or exercising any trust or power conferred
               upon the Trust Preferred Guarantee Trustee under this Trust
               Preferred Securities Guarantee; and

          (iv) no provision of this Trust Preferred Securities Guarantee shall
               require the Trust Preferred Guarantee Trustee to expend or risk
               its own funds or

                                      -8-



               otherwise incur personal financial liability in the performance
               of any of its duties or in the exercise of any of its rights or
               powers, if the Trust Preferred Guarantee Trustee shall have
               reasonable grounds for believing that the repayment of such funds
               or liability is not reasonably assured to it under the terms of
               this Trust Preferred Securities Guarantee or indemnity,
               reasonably satisfactory to the Trust Preferred Guarantee Trustee,
               against such risk or liability is not reasonably assured to it.

     Section 3.2 Certain Rights of Trust Preferred Guarantee Trustee.

          (a)  Subject to the provisions of Section 3.1(d) hereof:

          (i)  The Trust Preferred Guarantee Trustee may conclusively rely, and
               shall be fully protected in acting or refraining from acting
               upon, any resolution, certificate, statement, instrument,
               opinion, report, notice, request, direction, consent, order,
               bond, debenture, note, other evidence of indebtedness or other
               paper or document reasonably believed by it to be genuine and to
               have been signed, sent or presented by the proper party or
               parties.

          (ii) Any direction or act of the Guarantor contemplated by this Trust
               Preferred Securities Guarantee shall be sufficiently evidenced by
               an Officers' Certificate.

          (iii) Whenever, in the administration of this Trust Preferred
               Securities Guarantee, the Trust Preferred Guarantee Trustee shall
               deem it desirable that a matter be proved or established before
               taking, suffering or omitting any action hereunder, the Trust
               Preferred Guarantee Trustee (unless other evidence is herein
               specifically prescribed) may, in the absence of bad faith on its
               part, request and conclusively rely upon an Officers' Certificate
               which, upon receipt of such request, shall be promptly delivered
               by the Guarantor.

          (iv) The Trust Preferred Guarantee Trustee shall have no duty to see
               to any recording, filing or registration of any instrument (or
               any rerecording, refiling or reregistration thereof).

          (v)  The Trust Preferred Guarantee Trustee may consult with counsel,
               and the written advice or opinion of such counsel with respect to
               legal matters shall be full and complete authorization and
               protection in respect of any action taken, suffered or omitted by
               it hereunder in good faith and in accordance with such advice or
               opinion. Such counsel may be counsel to the Guarantor or any of
               its Affiliates and may include any of its employees. The Trust
               Preferred Guarantee Trustee shall have the right at any time to
               seek instructions concerning the administration of this Trust
               Preferred Securities Guarantee from any court of competent
               jurisdiction.

                                      -9-



          (vi) The Trust Preferred Guarantee Trustee shall be under no
               obligation to exercise any of the rights or powers vested in it
               by this Trust Preferred Securities Guarantee at the request or
               direction of any Holder, unless such Holder shall have provided
               to the Trust Preferred Guarantee Trustee such security and
               indemnity, reasonably satisfactory to the Trust Preferred
               Guarantee Trustee, against the costs, expenses (including
               reasonable attorneys' fees and expenses and the expenses of the
               Trust Preferred Guarantee Trustee's agents, nominees or
               custodians) and liabilities that might be incurred by it in
               complying with such request or direction, including such
               reasonable advances as may be requested by the Trust Preferred
               Guarantee Trustee; provided that, nothing contained in this
               Section 3.2(a)(vi) shall be taken to relieve the Trust Preferred
               Guarantee Trustee, upon the occurrence and during the continuance
               of an Event of Default, of which the Trust Preferred Guarantee
               has actual knowledge, of its obligation to exercise the rights
               and powers vested in it by this Trust Preferred Securities
               Guarantee.

          (vii) The Trust Preferred Guarantee Trustee shall not be bound to make
               any investigation into the facts or matters stated in any
               resolution, certificate, statement, instrument, opinion, report,
               notice, request, direction, consent, order, bond, debenture,
               note, other evidence of indebtedness or other paper or document,
               but the Trust Preferred Guarantee Trustee, in its discretion, may
               make such further inquiry or investigation into such facts or
               matters as it may see fit.

          (viii) The Trust Preferred Guarantee Trustee may execute any of the
               trusts or powers hereunder or perform any duties hereunder either
               directly or by or through agents, nominees, custodians or
               attorneys, and the Trust Preferred Guarantee Trustee shall not be
               responsible for any misconduct or negligence on the part of any
               agent or attorney appointed with due care by it hereunder.

          (ix) Any action taken by the Trust Preferred Guarantee Trustee or its
               agents hereunder shall bind the Holders of the Trust Preferred
               Securities, and the signature of the Trust Preferred Guarantee
               Trustee or its agents alone shall be sufficient and effective to
               perform any such action. No third party shall be required to
               inquire as to the authority of the Trust Preferred Guarantee
               Trustee to so act or as to its compliance with any of the terms
               and provisions of this Trust Preferred Securities Guarantee, both
               of which shall be conclusively evidenced by the Trust Preferred
               Guarantee Trustee's or its agent's taking such action.

          (x)  Whenever in the administration of this Trust Preferred Securities
               Guarantee the Trust Preferred Guarantee Trustee shall deem it
               desirable to receive instructions with respect to enforcing any
               remedy or right or taking any other action hereunder, the Trust
               Preferred Guarantee Trustee (i) may request instructions from the
               Holders of a Majority in Liquidation

                                      -10-



               Amount of the Trust Preferred Securities, (ii) may refrain from
               enforcing such remedy or right or taking such other action until
               such instructions are received, and (iii) shall be protected in
               conclusively relying on or acting in good faith in accordance
               with such instructions.

          (b) No provision of this Trust Preferred Securities Guarantee shall be
     deemed to impose any duty or obligation on the Trust Preferred Guarantee
     Trustee to perform any act or acts or exercise any right, power, duty or
     obligation conferred or imposed on it in any jurisdiction in which it shall
     be illegal, or in which the Trust Preferred Guarantee Trustee shall be
     unqualified or incompetent in accordance with applicable law, to perform
     any such act or acts or to exercise any such right, power, duty or
     obligation. No permissive power or authority available to the Trust
     Preferred Guarantee Trustee shall be construed to be a duty.

     Section 3.3 Not Responsible for Recitals or Issuance of Guarantee.

     The recitals contained in this Guarantee shall be taken as the statements
of the Guarantor, and the Trust Preferred Guarantee Trustee does not assume any
responsibility for their correctness. The Trust Preferred Guarantee Trustee
makes no representation as to the validity or sufficiency of this Trust
Preferred Securities Guarantee.

                                   ARTICLE IV

                        TRUST PREFERRED GUARANTEE TRUSTEE

     Section 4.1 Trust Preferred Guarantee Trustee; Eligibility.

          (a) There shall at all times be a Trust Preferred Guarantee Trustee
     which shall:

          (i)  not be an Affiliate of the Guarantor; and

          (ii) be an entity organized and doing business under the laws of the
               United States of America or any State or Territory thereof or of
               the District of Columbia, or a Person permitted by the Securities
               and Exchange Commission to act as a resident trustee under the
               Trust Indenture Act, authorized under such laws to exercise
               corporate trust powers, having a combined capital and surplus of
               at least $50,000,000, and subject to supervision or examination
               by applicable federal, state, territorial or District of Columbia
               authority. If such Person publishes reports of condition at least
               annually, pursuant to law or to the requirements of its
               supervising or examining authority referred to above, then, for
               the purposes of this Section 4.1(a)(ii), the combined capital and
               surplus of such Person shall be deemed to be its combined capital
               and surplus as set forth in its most recent report of condition
               so published.

                                      -11-



          (b) If at any time the Trust Preferred Guarantee Trustee shall cease
     to be eligible to so act under Section 4.1(a), the Trust Preferred
     Guarantee Trustee shall immediately resign in the manner and with the
     effect set out in Section 4.2(c).

          (c) If the Trust Preferred Guarantee Trustee has or shall acquire any
     "conflicting interest" within the meaning of Section 310(b) of the Trust
     Indenture Act and the provisions of the Trust Indenture Act are then
     applicable, the Trust Preferred Guarantee Trustee and Guarantor shall in
     all respects comply with the provisions of Section 310(b) of the Trust
     Indenture Act.

     Section 4.2 Appointment, Removal and Resignation of Trust Preferred
Guarantee Trustees.

          (a) Subject to Section 4.2(b), the Trust Preferred Guarantee Trustee
     may be appointed or removed without cause at any time by the Guarantor.

          (b) The Trust Preferred Guarantee Trustee shall not be removed in
     accordance with Section 4.2(a) until a Successor Trust Preferred Guarantee
     Trustee has been appointed and has accepted such appointment by written
     instrument executed by such Successor Trust Preferred Guarantee Trustee and
     delivered to the Guarantor and the Trust Preferred Guarantee Trustee.

          (c) The Trust Preferred Guarantee Trustee appointed to office shall
     hold office until a Successor Trust Preferred Guarantee Trustee shall have
     been appointed or until its removal or resignation. The Trust Preferred
     Guarantee Trustee may at any time resign from office (without need for
     prior or subsequent accounting) by an instrument in writing executed by the
     Trust Preferred Guarantee Trustee and delivered to the Guarantor, which
     resignation shall not take effect until a Successor Trust Preferred
     Guarantee Trustee has been appointed and has accepted such appointment by
     instrument in writing executed by such Successor Trust Preferred Guarantee
     Trustee and delivered to the Guarantor and the resigning Trust Preferred
     Guarantee Trustee.

          (d) If no Successor Trust Preferred Guarantee Trustee shall have been
     appointed and accepted appointment as provided in this Section 4.2 within
     60 days after delivery to the Guarantor of an instrument of resignation,
     the resigning Trust Preferred Guarantee Trustee may petition any court of
     competent jurisdiction for appointment of a Successor Trust Preferred
     Guarantee Trustee. Such court may thereupon, after prescribing such notice,
     if any, as it may deem proper, appoint a Successor Trust Preferred
     Guarantee Trustee.

          (e) No Trust Preferred Guarantee Trustee shall be liable for the acts
     or omissions to act of any Successor Trust Preferred Guarantee Trustee.

          (f) Upon termination of this Trust Preferred Securities Guarantee or
     removal or resignation of the Trust Preferred Guarantee Trustee pursuant to
     this Section 4.2, the Guarantor shall pay to the Trust Preferred Guarantee
     Trustee all documented fees and expenses accrued to the date of such
     termination, removal or resignation.

                                      -12-



                                    ARTICLE V

                                    GUARANTEE

     Section 5.1 Guarantee.

     The Guarantor irrevocably and unconditionally agrees to cause the Trust to
pay in full to the Holders the Guarantee Payments to the extent the Trust has
funds legally available therefor (without duplication of amounts theretofore
paid by the Trust), as and when due, regardless of any defense, right of set-off
or counterclaim that the Trust may have or assert.

     Section 5.2 Waiver of Notice and Demand.

     The Guarantor hereby waives notice of acceptance of this Trust Preferred
Securities Guarantee and of any liability to which it applies or may apply,
presentment, demand for payment, any right to require a proceeding first against
the Trust or any other Person before proceeding against the Guarantor, protest,
notice of nonpayment, notice of dishonor, notice of redemption and all other
notices and demands.

     Section 5.3 Obligations not Affected.

     The obligations, covenants, agreements and duties of the Guarantor under
this Trust Preferred Securities Guarantee shall in no way be affected or
impaired by reason of the happening from time to time of any of the following:

          (a) the release or waiver, by operation of law or otherwise, of the
     performance or observance by the Trust of any express or implied agreement,
     covenant, term or condition relating to the Trust Preferred Securities to
     be performed or observed by the Trust;

          (b) the extension of time for the payment by the Trust of all or any
     portion of the Distributions, Redemption Price, Liquidation Distribution or
     any other sums payable under the terms of the Trust Preferred Securities or
     the extension of time for the performance of any other obligation under,
     arising out of, or in connection with, the Trust Preferred Securities
     (other than an extension of time for payment of Distributions, Redemption
     Price, Liquidation Distribution or other sum payable that results from the
     extension of any interest payment period on the Debentures permitted by the
     Indenture);

          (c) any failure, omission, delay or lack of diligence on the part of
     the Holders to enforce, assert or exercise any right, privilege, power or
     remedy conferred on the Holders pursuant to the terms of the Trust
     Preferred Securities, or any action on the part of the Trust granting
     indulgence or extension of any kind;

          (d) the voluntary or involuntary liquidation, dissolution, sale of any
     collateral, receivership, insolvency, bankruptcy, assignment for the
     benefit of creditors, reorganization, arrangement, composition or
     readjustment of debt of, or other similar proceedings affecting, the Trust
     or any of the assets of the Trust;

                                      -13-



          (e) any invalidity of, or defect or deficiency in, the Trust Preferred
     Securities;

          (f) any failure or omission to receive any regulatory approval or
     consent required in connection with the Trust Preferred Securities (or the
     common equity securities issued by the Trust), including the failure to
     receive any approval of the Board of Governors of the Federal Reserve
     System required for the redemption of the Trust Preferred Securities;

          (g) the settlement or compromise of any obligation guaranteed hereby
     or hereby incurred; or

          (h) any other circumstance whatsoever that might otherwise constitute
     a legal or equitable discharge or defense of a guarantor, it being the
     intent of this Section 5.3 that the obligations of the Guarantor hereunder
     shall be absolute and unconditional under any and all circumstances.

     There shall be no obligation of the Holders to give notice to, or obtain
consent of, the Guarantor with respect to the happening of any of the foregoing.

     Section 5.4 Rights of Holders.

          (a) Subject to Section 5.4(b), the Holders of a Majority in
     Liquidation Amount of the Trust Preferred Securities have the right to
     direct the time, method and place of conducting of any proceeding for any
     remedy available to the Trust Preferred Guarantee Trustee in respect of
     this Trust Preferred Securities Guarantee or exercising any trust or power
     conferred upon the Trust Preferred Guarantee Trustee under this Trust
     Preferred Securities Guarantee.

          (b) Any Holder of Trust Preferred Securities may institute and
     prosecute a legal proceeding directly against the Guarantor to enforce its
     rights under this Trust Preferred Securities Guarantee, without first
     instituting and prosecuting a legal proceeding against the Trust, the Trust
     Preferred Guarantee Trustee or any other Person.

     Section 5.5 Guarantee of Payment.

     This Trust Preferred Securities Guarantee creates a guarantee of payment
and not of collection.

     Section 5.6 Subrogation.

     The Guarantor shall be subrogated to all (if any) rights of the Holders
against the Trust in respect of any amounts paid to such Holders by the
Guarantor under this Trust Preferred Securities Guarantee; provided, however,
that the Guarantor shall not (except to the extent required by mandatory
provisions of law) be entitled to enforce or exercise any right that it may
acquire by way of subrogation or any indemnity, reimbursement or other
agreement, in all cases as a result of payment under this Trust Preferred
Securities Guarantee, if, at the time of any such payment, any amounts are due
and unpaid under this Trust Preferred Securities Guarantee. If any

                                      -14-



amount shall be paid to the Guarantor in violation of the preceding sentence,
the Guarantor agrees to hold such amount in trust for the Holders and to pay
over such amount to the Holders.

     Section 5.7 Independent Obligations.

     The Guarantor acknowledges that its obligations hereunder are independent
of the obligations of the Trust with respect to the Trust Preferred Securities,
and that the Guarantor shall be liable as principal and as debtor hereunder to
make Guarantee Payments pursuant to the terms of this Trust Preferred Securities
Guarantee notwithstanding the occurrence of any event referred to in subsections
(a) through (h), inclusive, of Section 5.3 hereof.

                                   ARTICLE VI

                    LIMITATION OF TRANSACTIONS; SUBORDINATION

     Section 6.1 Limitation of Transactions.

     So long as any of the Trust Preferred Securities remain outstanding, if
there shall have occurred an Event of Default under this Trust Preferred
Securities Guarantee, an event of default under the Indenture, an event of
default under the Trust Agreement or during an Extended Interest Payment Period
(as defined in the Indenture), then

          (a) the Guarantor shall not, and will not permit any Subsidiary to,
     declare or pay any dividends on, make any distributions with respect to, or
     redeem, purchase, acquire or make a liquidation payment with respect to,
     any of its capital stock (other than (1) dividends or distributions in
     shares of, or options, warrants or rights to subscribe for or purchase
     shares of, common stock of the Guarantor or such Subsidiary, (2) any
     declaration of a dividend in connection with the implementation of a
     shareholder's rights plan, or the issuance of stock under any such plan in
     the future, or the redemption or repurchase of any such rights pursuant
     thereto, (3) purchases of common stock of the Guarantor related to the
     issuance of such common stock under any of the Guarantor's employee benefit
     plans for its directors, officers or employees, (4) as a result of a
     reclassification of any class or series of the Guarantor's capital stock
     solely into another class or series of the Guarantor's capital stock, or
     (5) declarations or payments of dividends or distributions payable by a
     Subsidiary of the Guarantor to the Guarantor or any of its Subsidiaries);

          (b) the Guarantor shall not, and will not permit any Subsidiary to,
     make any payment of interest, principal or premium, if any, or repay,
     repurchase or redeem any debt securities issued by the Guarantor which rank
     pari passu with or junior to the Debentures;

          (c) the Guarantor shall not make any guarantee payments with respect
     to any guarantee by the Guarantor of the debt securities of any Subsidiary
     of the Guarantor if such guarantee ranks pari passu with or junior in
     interest to the Debentures; provided, however, that the Guarantor may make
     payments pursuant to its obligations under the Trust Preferred Securities
     Guarantee; and

                                      -15-



          (d) the Guarantor shall not redeem, purchase or acquire less than all
     of the Outstanding (as defined in the Indenture) Debentures or any of the
     Trust Preferred Securities.

     Section 6.2 Ranking.

     This Trust Preferred Securities Guarantee will constitute an unsecured
obligation of the Guarantor and will rank subordinate and junior in right of
payment to all Senior Debt, Subordinated Debt and Additional Senior Obligations,
each as defined in the Indenture, of the Guarantor, to the extent and in the
manner set forth in the Indenture, and the applicable provisions of the
Indenture will apply, in all relevant respects, to the obligations of the
Guarantor hereunder.

                                   ARTICLE VII

                                   TERMINATION

     Section 7.1 Termination.

     This Trust Preferred Securities Guarantee shall terminate (a) upon full
payment of the Redemption Price of all Trust Preferred Securities, (b) upon full
payment of the amounts payable in accordance with the Trust Agreement upon
dissolution and liquidation of the Trust, or (c) upon distribution of the
Debentures to the Holders of the Trust Preferred Securities. Notwithstanding the
foregoing, this Trust Preferred Securities Guarantee shall continue to be
effective or shall be reinstated, as the case may be, if at any time any Holder
of Trust Preferred Securities must restore payment of any sums paid under the
Trust Preferred Securities or under this Trust Preferred Securities Guarantee.

                                  ARTICLE VIII

                                 INDEMNIFICATION

     Section 8.1 Exculpation.

          (a) No Indemnified Person shall be liable, responsible or accountable
     in damages or otherwise to the Guarantor or any Covered Person for any
     loss, damage or claim incurred by reason of any act or omission performed
     or omitted by such Indemnified Person in good faith in accordance with this
     Trust Preferred Securities Guarantee and in a manner that such Indemnified
     Person reasonably believed to be within the scope of the authority
     conferred on such Indemnified Person by this Trust Preferred Securities
     Guarantee or by law, except that an Indemnified Person shall be liable for
     any such loss, damage or claim incurred by reason of such Indemnified
     Person's negligence or willful misconduct with respect to such acts or
     omissions.

          (b) An Indemnified Person shall be fully protected in relying in good
     faith upon the records of the Guarantor and upon such information,
     opinions, reports or statements presented to the Guarantor or the
     Indemnified Person by any Person as to matters the Indemnified Person
     reasonably believes are within such other Person's

                                      -16-



     professional or expert competence and who the Indemnified Person reasonably
     believes has been selected with reasonable care by or on behalf of the
     Guarantor, including information, opinions, reports or statements as to the
     value and amount of the assets, liabilities, profits, losses, or any other
     facts pertinent to the existence and amount of assets from which
     Distributions to Holders of Trust Preferred Securities might properly be
     paid.

     Section 8.2 Indemnification.

     The Guarantor agrees to indemnify each Indemnified Person for, and to hold
each Indemnified Person harmless against, any loss, liability or expense
incurred without negligence or willful misconduct on its part, arising out of or
in connection with this Trust Preferred Securities Guarantee and the acceptance
or administration of the trust or trusts hereunder, including the costs and
expenses (including reasonable legal fees and expenses) of defending itself
against, or investigating, any claim or liability in connection with the
exercise or performance of any of its powers or duties hereunder, except as may
be otherwise prohibited by applicable law or regulation. The obligation to
indemnify as set forth in this Section 8.2 shall survive the termination of this
Trust Preferred Securities Guarantee.

                                   ARTICLE IX

                                  MISCELLANEOUS

     Section 9.1 Successors and Assigns.

     All guarantees and agreements contained in this Trust Preferred Securities
Guarantee shall bind the successors, assigns, receivers, trustees and
representatives of the Guarantor and shall inure to the benefit of the Holders
of the Trust Preferred Securities then outstanding.

     Section 9.2 Amendments.

     Except with respect to any changes that do not materially adversely affect
the rights of Holders (in which case no consent of Holders will be required),
this Trust Preferred Securities Guarantee may only be amended by the Guarantor
with the prior approval of the Holders of at least a Majority in Liquidation
Amount of the Trust Preferred Securities. The provisions of Article VI of the
Trust Agreement with respect to meetings of Holders apply to the giving of such
approval. Prior to the execution of any amendment to this Trust Preferred
Securities Guarantee, the Trust Preferred Guarantee Trustee shall be entitled to
receive and conclusively rely on an Opinion of Counsel stating that the
execution of such amendment is authorized or permitted by this Trust Preferred
Securities Guarantee and that all conditions precedent to such execution and
delivery have been satisfied. The Trust Preferred Guarantee Trustee may, but
shall not be obligated to, enter into any such amendment which affects the Trust
Preferred Guarantee Trustee's rights, duties or immunities under this Trust
Preferred Securities Guarantee, provided, however, that no such amendment shall
be effective without the consent of the Trust Preferred Guarantee Trustee.

                                      -17-



     Section 9.3 Notices.

     All notices provided for in this Trust Preferred Securities Guarantee shall
be in writing, duly signed by the party giving such notice, and shall be
delivered, telecopied or mailed by registered or certified mail, as follows:

          (a) If given to the Trust Preferred Guarantee Trustee, at the Trust
     Preferred Guarantee Trustee's mailing address set forth below (or such
     other address as the Trust Preferred Guarantee Trustee may give notice of
     to the Holders of the Trust Preferred Securities and the Guarantor):

                           Wells Fargo Bank, National Association

                           919 Market Street, Suite 700

                           Wilmington, Delaware 19801

                           Attention:  Corporate Trust Administration

          (b) If given to the Guarantor, at the Guarantor's mailing address set
     forth below (or such other address as the Guarantor may give notice of to
     the Holders of the Trust Preferred Securities and the Trust Preferred
     Guarantee Trustee):

                           Enterprise Financial Services Corp.

                           1281 N. Warson Road

                           St. Louis, MO 63132

                           Attention: Chief Executive Officer

          (c) If given to any Holder of Trust Preferred Securities, at the
     address set forth on the books and records of the Trust. All such notices
     shall be deemed to have been given when received in person, telecopied with
     receipt confirmed, or mailed by first class mail, postage prepaid except
     that if a notice or other document is refused delivery or cannot be
     delivered because of a changed address of which no notice was given, such
     notice or other document shall be deemed to have been delivered on the date
     of such refusal or inability to deliver.

     Section 9.4 Benefit.

     This Trust Preferred Securities Guarantee is solely for the benefit of the
Holders of the Trust Preferred Securities and the Trust Preferred Guarantee
Trustee and, subject to Section 3.1(a) and Section 4.2 hereof, as applicable is
not separately transferable from the Trust Preferred Securities.

     Section 9.5 Governing Law.

     THIS TRUST PREFERRED SECURITIES GUARANTEE SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF Delaware
WITHOUT REGARD TO ITS CHOICE OF LAW PROVISIONS.

                                      -18-



ANY ACTION OR PROCEEDING ARISING OUT OF THIS GUARANTEE, AS SUPPLEMENTED OR
AMENDED, IN ANY WAY SHALL BE BROUGHT AND ENFORCED EXCLUSIVELY IN THE APPLICABLE
UNITED STATES DISTRICT COURT FOR THE STATE OF Delaware, OR IN THE EVENT SUCH
COURT LACKS JURISDICTION, IN THE APPLICABLE Delaware STATE DISTRICT COURT.

                  [Remainder of Page Intentionally Left Blank]

                                      -19-



     IN WITNESS WHEREOF, this Trust Preferred Securities Guarantee is dated as
set forth below and effective as of June 27, 2002.

                                      Enterprise Financial Services Corp., as
                                      Guarantor


                                      By:
                                            ------------------------------------
                                      Name:
                                            ------------------------------------
                                      Title:
                                            ------------------------------------
                                      Date:
                                            ------------------------------------


                                      Wells Fargo Bank, National Association, a
                                      Trust Preferred Guarantee Trustee


                                      By:
                                            ------------------------------------
                                      Name:
                                            ------------------------------------
                                      Title:
                                            ------------------------------------
                                      Date:
                                            ------------------------------------

       [Signature Page to Trust Preferred Securities Guarantee Agreement]

                                            -20-