<PAGE>   1
As filed with the Securities and Exchange Commission on April 12, 1995

                                                       Registration No. 33-46944
________________________________________________________________________________
                                      
                      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)


                                      
                             PROGRESSIVE PARTNERS
                              STOCK OPTION 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 stock options issued pursuant
to 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



   

  On December 8, 1992, The Progressive Corporation (the "Company") effected a
3-for-1 split of the Company's Common Shares, $1.00 par value (the "Common
Shares"), in the form of a stock dividend.  Pursuant to the anti-dilution
provisions of the stock options awarded under the Progressive Partners Stock
Option Plan (the "Plan"), the number of Common Shares issuable under the Plan
was increased from 100,000 to 300,000 as a result of said 3-for-1 stock split.
Accordingly, the Company's Form S-8 Registration Statement (File No. 33-46944)
(the "Registration Statement") is hereby amended to confirm the registration
under the Securities Act of 1933, as amended (the "Act") of all 300,000 Common
Shares issuable under the Plan.  The Registration Statement is further amended
to provide that, pursuant to Rule 416(a) under the Act, 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 stock options awarded the 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 12, 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


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


Dated:  April 12, 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 12, 1995





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