Underwriting Agreement

Allegiant Bancorp, Inc.


Allegiant Capital Trust I


_________________________


1,725,000 9.875% Cumulative Trust Preferred Securities
(Liquidation Amount $10 per Trust Preferred Security)


July 27, 1999


UNDERWRITING AGREEMENT


EVEREN Securities, Inc.


Wheat First Securities


- -----------------------------------------------------------


Allegiant Bancorp, Inc.


Allegiant Capital Trust I


________________________________


1,725,000 9.875% Cumulative Trust Preferred Securities
(Liquidation Amount $10 per Trust Preferred Security)


UNDERWRITING AGREEMENT


July 27, 1999


EVEREN Securities, Inc. Wheat First Securities Individually and as Representatives of
the Several Underwriters c/o EVEREN Securities, Inc. 77 West Wacker Drive Chicago, Illinois 60601-1694


Ladies and Gentlemen:


Allegiant Bancorp, Inc., a Missouri corporation (the "Company"), and its fiduciary subsidiary, Allegiant Capital Trust I (the "Trust" and, together with the Company, the "Offerors"), a statutory business trust organized under the Delaware Business Trust Act (the "Delaware Act"), confirm their agreement with the several underwriters listed in Schedule I hereto (the "Underwriters"), for whom EVEREN Securities, Inc. and Wheat First Securities, a division of First Union Capital Markets Corp., have been duly authorized to act as representatives, with respect to the proposed issuance and sale by the Trust of its 9.875% Cumulative Trust Preferred Securities (liquidation amount $10 per security) representing undivided beneficial interests in the assets of the Trust (the "Trust Preferred Securities"). The Offerors propose that the Trust issue the Trust Preferred Securities pursuant to an Amended and Restated Trust Agreement among Bankers Trust Company, as property trustee (the "Property Trustee"), Bankers Trust (Delaware), as Delaware trustee (the "Delaware Trustee"), the administrators named therein (the "Administrators") and the Company (the "Trust Agreement"). The Trust Preferred Securities will be guaranteed by the Company with respect to distributions and payments upon liquidation, redemption and otherwise pursuant to a Guarantee Agreement (the "Guarantee Agreement") between the Company and Bankers Trust Company, as trustee (the "Guarantee Trustee"). The proceeds of the sale of the Trust Preferred Securities will be combined with the proceeds from the sale by the Trust to the Company of the Trust's common securities (the "Common Securities") and will be used to purchase 9.875% junior


subordinated debentures (the "Subordinated Debentures") issued by the Company pursuant to an Indenture ("Indenture") between the Company and Bankers Trust Company, as trustee (the "Indenture Trustee"). The Offerors hereby confirm their respective agreements with the Underwriters as follows:


1. The Trust Preferred Securities. The 1,500,000 Trust Preferred Securities proposed to be sold by the Trust are hereinafter referred to as the "Firm Securities." The Trust also proposes to grant to the Underwriters an option to purchase up to 225,000 additional Trust Preferred Securities (the "Additional Securities") if requested by the Underwriters as provided in Section 3 hereof. The Firm Securities and the Additional Securities are herein collectively called the "Securities."


2. Registration Statement and Prospectus. The Offerors have prepared and filed with the Securities and Exchange Commission (the "Commission") in accordance with the provisions of the Securities Act of 1933, as amended, and the rules and regulations (the "Rules and Regulations") of the Commission thereunder (collectively, the "Act"), and the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act"), a registration statement on Form S-2 (File Nos. 333-82197 and 333-82197-01) including a prospectus, relating to the Securities, the Subordinated Debentures and the Guarantee Agreement, that may have been amended; each such amendment was so prepared and filed. The registration statement, as amended at the time when it became or becomes effective, including all financial schedules (if any) and exhibits thereto, all information incorporated therein by reference and all of the information (if any) deemed to be part of the registration statement at the time of its effectiveness pursuant to Rule 430A under the Act ("Rule 430A"), is hereinafter referred to as the "Registration Statement"; the prospectus in the form first provided to the Underwriters by the Offerors in connection with the offering and sale of the Securities (whether or not required to be filed pursuant to Rule 424(b) under the Act ("Rule 424(b)")) is hereinafter referred to as the "Prospectus," except that if any revised prospectus shall be provided to the Underwriters by the Offerors for use in connection with the offering of the Securities that differs from the Prospectus (whether or not any such revised prospectus is required to be filed by the Offerors pursuant to Rule 424(b)), the term "Prospectus" shall refer to the revised prospectus from and after the time it is first provided to the Underwriters for such use; and each preliminary prospectus included in the Registration Statement prior to the time it became or becomes effective is herein referred to as a "Preliminary Prospectus."


3. Agreements to Sell and Purchase. On the basis of the representations and warranties contained in this Agreement, and subject to the terms and conditions hereof, (i) the Trust agrees to issue and sell to the Underwriters, at a price of $10.00 per Security (the "Purchase Price"), 1,500,000 Firm Securities; and (ii) each Underwriter agrees, severally and not jointly, to purchase from the Trust, at the Purchase Price, the aggregate number of Firm Securities set forth opposite the name of such Underwriter in Schedule I hereto. As compensation to the Underwriters for their commitments hereunder and in view of the fact that the proceeds of the sale of the Securities (together with the proceeds from the sale by the Trust to the Company of the Common Securities)


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will be used to purchase the Subordinated Debentures, the Company hereby agrees to pay at the Closing Date (as herein defined) to the Underwriters a commission per Security equal to $0.375 per Security, or $562,500 in the aggregate ($646,875 if the over-allotment with respect to the Additional Securities is exercised in full).


On the basis of the representations and warranties contained in this Agreement, and subject to the terms and conditions hereof, (i) the Trust agrees to sell to the Underwriters, at the Purchase Price, up to 225,000 Additional Securities; and (ii) the Underwriters shall have the right to purchase, severally and not jointly, from time to time, up to an aggregate of 225,000 Additional Securities at the Purchase Price. Additional Securities may be purchased as provided in Section 4 hereof solely for the purpose of covering over-allotments made in connection with the offering of the Firm Securities. If any Additional Securities are to be purchased, each Underwriter, severally and not jointly, agrees to purchase the number of Additional Securities that bears the same proportion to the total number of Additional Securities to be purchased as the number of Firm Securities set forth opposite the name of such Underwriter in Schedule I bears to the total number of Firm Securities.


4. Agreements of the Offerors as to Delivery and Payment. The Offerors agree with each Underwriter that:


(a) Delivery to the Underwriters of, and payment to
the Trust for, the Firm Securities shall be made at 10:00 A.M.,
Chicago time, on the third (or if the Firm Securities are priced,
as contemplated by Rule 15c6-1(c) under the Securities Exchange
Act of 1934, as amended (the "Exchange Act"), after 4:30 p.m.
Eastern time, on the fourth) full business day (such time and date
being referred to as the "Closing Date") following the date of the
initial public offering of the Firm Securities as advised to you
by the Company, at such place as you shall designate.


(b) Delivery to the Underwriters of and payment for
any Additional Securities to be purchased by the Underwriters
shall be made at such place as you shall designate, at 10:00 A.M.,
Chicago time, on such date or dates (individually, an "Option
Closing Date" and collectively, the "Option Closing Dates"), which
may be the same as the Closing Date but shall in no event be
earlier than the Closing Date, as shall be specified in a written
notice from you to the Offerors of the Underwriters' determination
to purchase a number, specified in said notice, of Additional
Securities. Any such notice may be given at any time within 30
days after the date of this Agreement.


(c) The Securities will be delivered by the Trust to
the Underwriters on the Closing Date or the applicable Option
Closing Date against payment of the Purchase Price therefor by
certified or official bank check or wire transfer of immediately
available funds payable to the order of the Trust to an account
designated by the Trust. Delivery of the Securities may be made
by credit through full fast transfer to the accounts at The
Depository Trust Company designated by


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you. Certificates representing the Securities, in definitive form
and in such denominations and registered in such names as you may
request in writing not less than two business days prior to the
Closing Date or the applicable Option Closing Date notice to the
Offerors shall be prepared and will be made available for
inspection not later than 9:30 A.M., Chicago time, on the business
day next preceding the Closing Date or the applicable Option
Closing Date, with any transfer taxes payable upon initial
issuance or the transfer thereof duly paid by the Company for the
respective accounts of the Underwriters against payment of the
Purchase Price therefor.


5. Further Agreements of the Offerors. The Offerors also agree with each Underwriter that:


(a) they will, if the Registration Statement has not
heretofore become effective under the Act, file an amendment to
the Registration Statement or, if necessary pursuant to Rule 430A
under the Act, a post-effective amendment to the Registration
Statement, as soon as practicable after the execution and delivery
of this Agreement, and will use their best efforts to cause the
Registration Statement or such post-effective amendment to become
effective at the earliest possible time; and the Offerors will
comply fully and in a timely manner with the applicable provisions
of Rule 424(b) and Rule 430A under the Act;


(b) they will advise you promptly and, if requested
by you, confirm such advice in writing, (i) when the Registration
Statement has become effective, if and when the Prospectus is sent
for filing pursuant to Rule 424 under the Act and when any post-
effective amendment to the Registration Statement becomes
effective, (ii) of the receipt of any comments from the Commission
that relate to the Registration Statement or requests by the
Commission for amendments to the Registration Statement or
amendments or supplements to the Prospectus or for additional
information, (iii) of the issuance by the Commission of any stop
order suspending the effectiveness of the Registration Statement,
or of the suspension of qualification of the Securities for
offering or sale in any jurisdiction, or the initiation or, to the
best knowledge of the Offerors, threat of any proceedings for such
purpose by the Commission or any state securities commission or
other regulatory authority, and (iv) of the happening of any event
or information becoming known during the period referred to in
paragraph (e) below that makes any statement of a material fact
made in the Registration Statement untrue or that requires the
making of any additions to or changes in the Registration
Statement (as amended or supplemented from time to time) in order
to make the statements therein not misleading or that makes any
statement of a material fact made in the Prospectus (as amended or
supplemented from time to time) untrue or that requires the making
of any additions to or changes in the Prospectus (as amended or
supplemented from time to time) in order to make the statements
therein, not misleading; if at any time the Commission shall issue
or institute proceedings (or threaten to institute any such
proceedings) to issue any stop order suspending the


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effectiveness of the Registration Statement, or any state
securities commission or other regulatory authority shall issue or
institute proceedings (or threaten to institute proceedings) to
issue an order suspending the qualification or exemption of the
Securities under any state securities or blue sky laws, the
Offerors shall use best efforts to obtain the withdrawal or
lifting of such order at the earliest possible time;


(c) they will furnish to you without charge one
signed copy of the Registration Statement as first filed with the
Commission and of each amendment to it, including all exhibits
filed therewith, and will furnish to you and each Underwriter
designated by you such number of conformed copies of the
Registration Statement as so filed and of each amendment to it,
without exhibits, as you may reasonably request;


(d) they will not file any amendment or supplement
to the Registration Statement, whether before or after the time
when it becomes effective, or make any amendment or supplement to
the Prospectus of which you shall not previously have been advised
and provided a copy a reasonable period of time prior to the
filing thereof or to which you or your counsel shall reasonably
object, and they will prepare and file with the Commission,
promptly upon your reasonable request, any amendment to the
Registration Statement or supplement to the Prospectus that may be
necessary or advisable in connection with the distribution of the
Securities by you in your or your counsel's opinion, and will use
best efforts to cause the same to become effective as promptly as
possible;


(e) promptly after the Registration Statement
becomes effective, and from time to time thereafter for such
period as a prospectus is required by the Act to be delivered in
connection with the sales by an underwriter or a dealer (in the
opinion of your counsel), they will furnish to each Underwriter
and dealer without charge as many copies of the Prospectus (and
any amendment or supplement to the Prospectus) as such Underwriter
or dealer may reasonably request for the purposes contemplated by
the Act, and the Offerors consent to the use of the Prospectus and
any amendment or supplement thereto by any Underwriter or any
dealer, both in connection with the offering or sale of the
Securities and for such period of time thereafter as the
Prospectus is required by the Act to be delivered in connection
therewith;


(f) if during the period specified in paragraph
(e) any event shall occur or information become known as a result
of which in the opinion of your counsel it becomes necessary to
amend or supplement the Prospectus in order to make the statements
therein as of the date the Prospectus is delivered to a purchaser,
in light of the circumstances under which such statements were
made, not misleading, or it is necessary to amend or supplement
the Prospectus to comply with any law, forthwith to prepare and,
subject to paragraph 5(d) above, they will file with the
Commission at the sole expense of the Company an appropriate


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amendment or supplement to the Prospectus so that the statements
of any material facts in the Prospectus, as so amended and
supplemented, will not when it is so delivered, in light of the
circumstances under which such statements are made, be misleading,
or so that the Prospectus will comply with law and it will furnish
to the Underwriters and to such dealers as the Underwriters shall
specify, at the sole expense of the Company, such number of copies
thereof as such Underwriters or dealers may reasonably request;


(g) prior to any public offering of the Securities,
they will cooperate with you and counsel for the Underwriters in
connection with the registration or qualification of the
Securities for offer and sale by the several Underwriters and by
dealers under the state securities or blue sky laws of such
jurisdictions as you may reasonably request (provided that the
Offerors shall not be obligated to qualify as foreign corporations
in any jurisdiction in which they are not so qualified or to take
any action that would subject them to general consent to service
of process in any jurisdiction in which they are not now so
subject), and the Offerors will continue such qualification in
effect so long as required by law for the distribution of the
Securities and will file such consents to service of process or
other documents as may be necessary in order to effect such
registration or qualification (provided that the Offerors shall
not be obligated to take any action that would subject it to
general consent to service of process in any jurisdiction in which
they are not now so subject);


(h) they will not, prior to the exercise in full or
termination or expiration of the option to purchase the Option
Securities, incur any liability or obligation, direct or
contingent, or enter into any material transaction, other than in
the ordinary course of business, except as contemplated by the
Prospectus;


(i) they will make generally available to their
security holders and furnish to the Underwriters as soon as
reasonably practicable a consolidated earning statement covering a
period of at least 12 months beginning after the "effective date"
(as defined in Rule 158 under the Act) of the Registration
Statement (but in no event commencing later than 90 days after
such date) that will satisfy the provisions of Section 11(a) of
the Act and Rule 158 thereunder, and will advise you in writing
when such statement has been made so available;


(j) during the period of five years after the date
of this Agreement, they will furnish to you a copy: (i) as soon
as practicable after the filing thereof, of each report filed by
either of the Offerors with the Commission, any securities
exchange or the National Association of Securities Dealers, Inc.
("NASD"); (ii) as soon as practicable after the release thereof,
of each material press release in respect of either of the
Offerors; (iii) as soon as available, of each report of the
Company mailed to shareholders; and (iv) as soon as available,
such other publicly available information concerning the Offerors
as you may reasonably request;


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(k) whether or not the transactions contemplated
hereby are consummated or this Agreement becomes effective as to
all of its provisions or is terminated, to pay all costs, fees,
expenses and taxes incident to the performance by the Offerors of
their obligations hereunder, including (i) the preparation,
printing, filing and distribution under the Act of the
Registration Statement (including financial statements and
exhibits), each Preliminary Prospectus and all amendments and
supplements to any of them prior to or during the period specified
in paragraph (e) above of this Section 5, (ii) the word
processing, reproduction and distribution of this Agreement, the
Blue Sky Survey and any other agreements, memoranda,
correspondence and other documents prepared and delivered by the
Underwriters or their counsel in connection with the offering of
the Securities (including in each case any disbursements of
counsel for the Underwriters relating to such preparation and
delivery), (iii) the registration or qualification of the
Securities for offer and sale under the securities or blue sky
laws of the several states, including in each case the fees and
disbursements of counsel for the Underwriters, relating to such
registration or qualification and memoranda relating thereto;
provided however, in no event shall such fees and disbursements
exceed $5,000, (iv) filings and clearance with the NASD in
connection with the offering and sale of the Securities, (v) the
listing of the Securities on the American Stock Exchange ("AMEX"),
(vi) furnishing such copies of the Registration Statement, each
Preliminary Prospectus, the Prospectus and all amendments and
supplements thereto as may be requested for use in connection with
the offering or sale of the Securities by the Underwriters or by
dealers to whom the Securities may be sold, (vii) obtaining the
opinions to be provided pursuant to Sections 8(f), 8(g) and 8(h)
of this Agreement and (viii) the performance by the Offerors of
all of their other obligations under this Agreement; provided that
if the sale of the Securities provided for herein is not
consummated because the Underwriters exercise their right to
terminate this Agreement pursuant to Section 9 hereof and any of
the following have occurred during the term of this Agreement:
(a) there has been any material adverse change in the condition
(financial or otherwise), earnings, affairs, business or prospects
of the Company, or (b) either Offeror shall refuse or be unable to
comply with any provision hereof (except as the result of a breach
of this Agreement by the Underwriters), the Company will promptly
reimburse the Underwriters upon demand for all reasonable out-of-
pocket expenses (including the fees and disbursements of counsel
for the Underwriters) that shall have been incurred by the
Underwriters in connection with the proposed purchase and sale of
Securities;


(l) they will use the net proceeds received by them
from the sale of the Securities and the Subordinated Debentures in
the manner specified in the Prospectus and will file such reports
with the Commission with respect to the application of the
proceeds therefrom as may be required in accordance with Rule 463
under the Act and will furnish you copies of any such reports as
soon as practicable after the filing thereof;


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(m) if, at the time of effectiveness of the
Registration Statement, any information shall have been omitted
therefrom in reliance upon Rule 430A, then immediately following
the execution and delivery of this Agreement, they will prepare,
and file, or transmit for filing with the Commission in accordance
with such Rule 430A and Rule 424(b), copies of an amended
prospectus, or, if required by such Rule 430A, a post-effective
amendment to the Registration Statement (including an amended
prospectus), containing all information so omitted;


(n) they will cause the Securities to be listed,
subject to notice of issuance or sale, on AMEX and will comply
with all registration, filing and reporting requirements of AMEX;


(o) they will not take, directly or indirectly, any
action designed to or which might reasonably be expected to
constitute, cause or result in, under the Exchange Act or
otherwise, the stabilization or manipulation of the price of any
security of either Offeror to facilitate the sale or resale of the
Securities;


(p) they will inform the Florida Department of
Banking and Finance at any time prior to the consummation of the
distribution of the Securities by the Underwriters if either of
them commences engaging in business with the government of Cuba or
with any person or affiliate located in Cuba, with such
information to be provided within 90 days after the commencement
thereof or after a change occurs with respect to previously
reported information;


(q) they will use their best efforts to do and
perform all things required to be done and performed under this
Agreement by them prior to or after the Closing Date or any Option
Closing Date, as the case may be, and to satisfy all conditions
precedent to the delivery of the Securities;


(r) the Offerors will not distribute any prospectus
or other offering material in connection with the offering and
sale of the Securities other than any Preliminary Prospectus or
the Prospectus or other materials permitted by the Act to be
distributed by the Company; and


(s) in the event that the Subordinated Debentures
are distributed to the holders of the Securities for any reason,
the Offerors will use their respective best efforts to cause the
Subordinated Debentures to be listed, subject to notice of
issuance, at the time of such distribution, upon the American
Stock Exchange, such other securities exchange or exchanges and/or
the Nasdaq National Market upon which the Securities are then
listed. The Company will thereafter comply with all registration,
filing and reporting requirements of the American Stock Exchange
or such other exchange or Nasdaq National Market upon which the
Subordinated Debentures are listed.


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6. Representations and Warranties.


(a) The Offerors jointly and severally represent and
warrant to, and agree with, each Underwriter as of the date
hereof, the Closing Date and each Option Closing Date (except for
such representations that are specified as being made as of a
particular date) as follows:


(i) The Commission has not issued any order
preventing or suspending the use of any Preliminary
Prospectus relating to the proposed offering of the
Securities nor instituted or threatened any proceedings
for that purpose. The Registration Statement, on the
date it was or is declared effective by the Commission,
each Preliminary Prospectus, on the date of the filing
thereof with the Commission, and the Prospectus and any
amendment or supplement thereto, on the date of filing
...