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                                                                 Exhibit 4.7

                               TRUST AGREEMENT
                               ---------------

     This TRUST AGREEMENT, dated as of June 6, 2001 (this "Trust
Agreement"), by and between Allegiant Bancorp, Inc., a Missouri corporation
(the "Depositor"), and Bankers Trust (Delaware), a Delaware banking
corporation (the "Trustee"). The Depositor and the Trustee hereby agree as
follows:

          1. The trust created hereby (the "Trust") shall be known as "Allegiant
Capital Trust II" in which name the Trustee, or the Depositor to the extent
provided herein, may engage in the transactions contemplated hereby, make
and execute contracts, and sue and be sued.

          2. The Depositor hereby assigns, transfers conveys and sets over to
the Trustee the sum of $10. The Trustee hereby acknowledges receipt of such
amount in trust from the Depositor, which amount shall constitute the
initial trust estate. The Trustee hereby declares that it will hold the
trust estate in trust for the Depositor. It is the intention of the parties
hereto that the Trust created hereby constitute a business trust under
Chapter 38 of Title 12 of the Delaware Code, 12 Del. C. Section 3801, et seq.
                                                -------               -- ---
(the "Business Trust Act"), and that this document constitutes the
governing instrument of the Trust. The Trustee is hereby authorized and
directed to execute and file a certificate of trust with the Delaware
Secretary of State in accordance with the provisions of the Business Trust
Act.

          3. The Depositor and the Trustee will enter into an amended and
restated Trust Agreement, satisfactory to each such party and substantially
in the form included as an exhibit to the 1933 Act Registration Statement
(as defined below), to provide for the contemplated operation of the Trust
created hereby and the issuance of the Preferred Securities and Common
Securities referred to therein. Prior to the execution and delivery of
such amended and restated Trust Agreement, the Trustee shall not have any
duty or obligation hereunder or with respect to the trust estate, except as
otherwise required by applicable law or as may be necessary to obtain prior
to such execution and delivery any licenses, consents or approvals required
by applicable law or otherwise.

          4. The Depositor and the Trustee hereby authorize and direct the
Depositor, as the sponsor of the Trust, (i) to file with the Securities and
Exchange Commission (the "Commission") and execute, in each case on behalf
of the Trust, (a) the Registration Statement on Form S-3 (the "1933 Act
Registration Statement"), including any pre-effective or post-effective
amendments to the 1933 Act Registration Statement, relating to the
registration under the Securities Act of 1933, as amended, of the Preferred
Securities of the Trust and possibly certain other securities and (b) a
Registration Statement on Form 8-A (the "1934 Act Registration Statement")
(including all pre-effective and post-effective amendments thereto) relating
to the registration of the Preferred Securities of the Trust under the
Securities Exchange Act of 1934, as amended; (ii) to file with The Nasdaq
National Market (the "Exchange") and execute on behalf of the Trust one or
more listing applications and all other applications, statements,
certificates, agreements and other instruments as shall be necessary or
desirable to cause the Preferred Securities to be listed on the Exchange;
(iii) to file and


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execute on behalf of the Trust such applications, reports, surety
bonds, irrevocable consents, appointments of attorney for service of process
and other papers and documents as shall be necessary or desirable to
register the Preferred Securities under the securities or "blue sky" laws
of such jurisdictions as the Depositor, on behalf of the Trust, may deem
necessary or desirable; and (iv) to execute on behalf of the Trust that
certain Underwriting Agreement relating to the Preferred Securities, among
the Trust, the Depositor and the several Underwriters named therein,
substantially in the form included as an exhibit to the 1933 Act
Registration Statement.

     In connection with the filings referred to above, the Depositor hereby
constitutes and appoints Shaun R. Hayes and Thomas A. Daiber, and each of
them, as its true and lawful attorneys-in-fact and agents, with full power
of substitution and resubstitution, for the Depositor or in the Depositor's
name, place and stead, in any and all capacities, to sign any and all
amendments (including post-effective amendments) to the 1933 Act Registration
Statement and the 1934 Act Registration Statement and to file the same, with
all exhibits thereto, and other documents in connection therewith, with the
Commission, the Exchange and administrators of state securities or "blue sky"
laws, granting unto said attorneys-in-fact and agents full power and authority
to do and perform each and every act and thing requisite and necessary to be
done in connection therewith, as fully to all intents and purposes as the
Depositor might or could to in person, hereby ratifying and confirming all
that said attorneys-in-fact and agents or any of them, or their respective
substitute or substitutes, shall do or cause to be done by virtue hereof.

          5. This Trust Agreement may be executed in one or more counterparts.

          6. The number of Trustees initially shall be one (1) and thereafter
the number of Trustees shall be such number as shall be fixed from time to
time by a written instrument signed by the Depositor which may increase or
decrease the number of Trustees; provided, however, that to the extent
required by the Business Trust Act, one Trustee shall either be a natural
person who is a resident of the State of Delaware or, if not a natural
person, an entity which has its principal place of business in the State of
Delaware and otherwise meets the requirements of applicable Delaware law.
Subject to the foregoing, the Depositor is entitled to appoint or remove
without cause any Trustee at any time. The Trustees may resign upon thirty
(30) days' prior notice to the Depositor.

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          7. This Trust Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware (without regard to
conflict of laws of principles).

          8. This Trust Agreement may be amended by written agreement of the
parties hereto.



                          [SIGNATURE PAGE FOLLOWS]

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     IN WITNESS WHEREOF, the parties hereto have caused this Trust Agreement
to be duly executed as of the day and year first above written.


                                     ALLEGIANT BANCORP, INC.,
                                     as Depositor


                                     By: /s/ Thomas A. Daiber
                                        -----------------------------------
                                     Name: Thomas A. Daiber
                                     Title: Executive Vice President


                                     BANKERS TRUST (DELAWARE),
                                     as Trustee


                                     By: /s/ Elizabeth B. Ferry
                                        -----------------------------------
                                     Name: Elizabeth B. Ferry
                                     Title: Trustee



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