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Exhibit 31.1

                               CERTIFICATIONS

I, Shaun R. Hayes, certify that:

1.   I have reviewed this annual report on Form 10-K of Allegiant Bancorp,
     Inc.;

2.   Based on my knowledge, this annual report does not contain any untrue
     statement of a material fact or omit to state a material fact necessary
     to make the statements made, in light of the circumstances under which
     such statements were made, not misleading with respect to the period
     covered by this annual report;

3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows
     of the registrant as of, and for, the periods presented in this annual
     report;

4.   The registrant's other certifying officers and I are responsible for
     establishing and maintaining disclosure controls and procedures (as
     defined in Exchange Act Rules 13a-14 and 15d-14) for the registrant and
     have:

         (a)  designed such disclosure controls and procedures to ensure
              that material information relating to the registrant,
              including its consolidated subsidiaries, is made known to us
              by others within those entities, particularly during the
              period in which this annual report is being prepared;

         (b)  evaluated the effectiveness of the registrant's disclosure
              controls and procedures as of a date within 90 days prior to
              the filing date of this annual report (the "Evaluation Date");
              and

         (c)  presented in this annual report our conclusions about the
              effectiveness of the disclosure controls and procedures based
              on our evaluation as of the Evaluation Date;

5.   The registrant's other certifying officers and I have disclosed, based
     on our most recent evaluation, to the registrant's auditors and the
     audit committee of the registrant's board of directors (or persons
     performing the equivalent function):

         (a)  all significant deficiencies in the design or operation of
              internal controls which could adversely affect the
              registrant's ability to record, process, summarize and report
              financial data and have identified for the registrant's
              auditors any material weaknesses in internal controls; and

         (b)  any fraud, whether or not material, that involves management
              or other employees who have a significant role in the
              registrant's internal controls; and

6.   The registrant's other certifying officers and I have indicated in this
     annual report whether or not there were significant changes in internal
     controls or in other factors that could significantly affect internal
     controls subsequent to the date of our most recent evaluation,
     including any corrective actions with regard to significant
     deficiencies and material weaknesses.

January 30, 2004                       By: /s/ Shaun R. Hayes
                                          ----------------------------------
                                           Shaun R. Hayes, President and
                                              Chief Executive Officer