UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                    FORM 8-K

                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported)         April 19, 2004
                                                 -------------------------------

                         Cass Information Systems, Inc.
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             (Exact Name of Registrant as Specified in its Charter)

                                    Missouri
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                 (State or Other Jurisdiction of Incorporation)

        2-80070                                            43-1265338
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(Commission File Number)                       (IRS Employer Identification No.)

13001 Hollenberg Drive, Bridgeton, Missouri                   63044
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 (Address of Principal Executive Offices)                   (Zip Code)

                                 (314) 506-5500
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              (Registrant's Telephone Number, Including Area Code)

                                       N/A
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          (Former Name or Former Address, if Changed Since Last Report)



                         CASS INFORMATION SYSTEMS, INC.

                                    FORM 8-K

Item 7. Financial Statements and Exhibits.

(c) Exhibits

    Exhibit No.   Description
    -----------   -----------

       99.1       Press Release dated April 19, 2004, issued by Cass Information
                  Systems, Inc. (the Registrant)

Item 12. Results of Operations and Financial Condition

      On April 19, 2004, the registrant issued a press release announcing its
preliminary results of operations for the quarter ended March 31, 2004. A copy
of the press release is attached hereto as Exhibit 99.1 and hereby incorporated
by reference. The information in this Form 8-K shall not be deemed to be "filed"
for the purposes of Section 18 of the Securities Exchange Act of 1934 (the
"Exchange Act"), or otherwise subject to the liabilities of such section, nor
shall such information be deemed incorporated by reference in any filing under
the Securities Act of 1933 or the Exchange Act, except as shall be expressly set
forth by specific reference in such a filing.


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                                   SIGNATURES

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                            Cass Information Systems, Inc.


April 19, 2004                      By:         /s/ Lawrence A. Collett
                                        ----------------------------------------
                                                  Lawrence A. Collett
                                         Chairman and Chief Executive Officer


April 19, 2004                      By:         /s/ Eric H. Brunngraber
                                        ----------------------------------------
                                                 Eric H. Brunngraber
                                               Vice President-Secretary
                                        (Chief Financial and Accounting Officer)


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                                  EXHIBIT INDEX

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

99.1            Press Release dated April 19, 2004.


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