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)               October 26, 2004 (October 21, 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)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[_]  Written communications pursuant to Rule 425 under the Securities Act (17
     CFR 230.425)

[_]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
     240.14a-12)

[_]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[_]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (17 CFR 240.13e-4(c))




                         CASS INFORMATION SYSTEMS, INC.

                                    FORM 8-K



ITEM 2.02. RESULTS OF OPERATIONS AND FINANCIAL CONDITION.

     On October 21, 2004, the registrant issued a press release announcing its
preliminary results of operations for the quarter ended September 30, 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.

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS.

(c)  Exhibits

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

         99.1         Press Release  dated  October 21, 2004,  issued by Cass
                      Information  Systems,  Inc. (the Registrant)


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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.


October 26, 2004                        By: /s/ Lawrence A. Collett   
                                        ---------------------------   
                                        Lawrence A. Collett
                                        Chairman and Chief Executive Officer

October 26, 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 October 21, 2004.


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