<PAGE>   1
As filed with the Securities and Exchange Commission on April 19, 1995

                                                       Registration No. 33-64210
________________________________________________________________________________
                                      
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549
                                      
                        POST-EFFECTIVE AMENDMENT NO. 1
                                      to
                                   FORM S-8
                            REGISTRATION STATEMENT
                                    Under
                          THE SECURITIES ACT OF 1933
                                      
                         THE PROGRESSIVE CORPORATION
            (Exact name of registrant as specified in its charter)

               OHIO                                  34-0963169
  (State or other jurisdiction of          (I.R.S. Employer Identification
  incorporation or organization)           Number)




            6300 Wilson Mills Road, Mayfield Village, Ohio  44143
           (Address of Principal Executive Offices)      (Zip Code)



                         THE PROGRESSIVE CORPORATION
                             1989 INCENTIVE PLAN
                           (Full title of the plan)

                        David M. Schneider, Secretary
                         The Progressive Corporation
                            6300 Wilson Mills Road
                        Mayfield Village, Ohio  44143
                   (Name and address of agent for service)

                                (216) 461-5000
        (Telephone number, including area code, of agent for service)



  Pursuant to Rule 416(a) under the Securities Act of 1933, the amount of
securities registered under the Registration Statement shall include an
indeterminate number of additional Common Shares that may become issuable
pursuant to the anti-dilution provisions of the Plan.

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                        POST-EFFECTIVE AMENDMENT NO. 1
                                      
                                      TO
                                      
                       FORM S-8 REGISTRATION STATEMENT
                                      
                   - - - - - - - - - - - - - - - - - - - -
                                      
                         THE PROGRESSIVE CORPORATION
                                      
                   - - - - - - - - - - - - - - - - - - - -
                                      
                    REGISTRATION COVERS SHARES ISSUABLE 
                   TO PREVENT DILUTION RESULTING FROM STOCK
               SPLITS, STOCK DIVIDENDS OR SIMILAR TRANSACTIONS




   
  The Registration Statement is hereby amended to provide that, pursuant to
Rule 416(a) under the Securities Act of 1933, as amended, the amount of
securities registered under the Registration Statement shall include an
indeterminate number of additional Common Shares that may become issuable
pursuant to the anti-dilution provisions of The Progressive Corporation 1989
Incentive Plan.
    




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                                  SIGNATURES


  The Registrant.  Pursuant to the requirements of the Securities Act of 1933,
the Registrant certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
Post-Effective Amendment No. 1 to the Registration Statement to be signed on
its behalf by the undersigned, thereunto duly authorized, in Mayfield Village,
Ohio, on April 19, 1995.

                                        THE PROGRESSIVE CORPORATION


                                        By:/s/David M. Schneider     
                                          ---------------------------------
                                          David M. Schneider, Secretary


  Pursuant to the requirements of the Securities Act of 1933, this
Post-Effective Amendment No. 1 to the Registration Statement has been signed by
the following persons in the capacities and on the date indicated below.


    Signature                               Title
    ---------                               -----


    Peter B. Lewis*             Chairman of the Board, President and Director  
- --------------------------      (Principal Executive Officer)
    Peter B. Lewis


    /s/Charles B. Chokel        Principal Financial Officer
- --------------------------
    Charles B. Chokel


    /s/Jeffrey W. Basch         Principal Accounting Officer
- --------------------------
    Jeffrey W. Basch


    Milton N. Allen*            Director
- --------------------------
    Milton N. Allen


    B. Charles Ames*            Director
- --------------------------
    B. Charles Ames


    Stephen R. Hardis*          Director
- --------------------------
    Stephen R. Hardis





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    Norman S. Matthews*                 Director
- -------------------------------         
    Norman S. Matthews


    Donald B. Shackelford*              Director
- -------------------------------         
    Donald B. Shackelford

                                        Director
- -------------------------------         
    Paul B. Sigler


Dated:  April 19, 1995




  *  David M. Schneider, by signing his name hereto, does sign this document on
     behalf of the persons indicated above pursuant to powers of attorney duly
     executed by such persons and filed as an exhibit to the Registration
     Statement.


  By:  /s/David M. Schneider    
       -------------------------------
       David M. Schneider
       Attorney-in-fact


  Dated:  April 19, 1995





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