American Century California Tax Free & Municipal Funds N-CSR Certified annual shareholder report (management investment company)

                                                              EXHIBIT 99.906CERT



     Certification Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
     -----------------------------------------------------------------------

     In connection with the shareholder  report of American  Century  California
Tax-Free and  Municipal  Funds (the  "Registrant")  on Form N-CSR for the period
ending August 31, 2005 (the "Report"), we, the undersigned, certify, pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002, that:

          (1)  The Report fully complies with the  requirements of Section 15(d)
               of the Securities Exchange Act of 1934; and

          (2)  The information  contained in the Report fairly presents,  in all
               material  respects,   the  financial  condition  and  results  of
               operations of the Registrant.



Dated:  October 28, 2005



                                         /s/ William M. Lyons
                                         ---------------------------------------
                                         William M. Lyons
                                         President
                                         (chief executive officer)



                                         /s/ Maryanne L. Roepke
                                         ---------------------------------------
                                         Maryanne L. Roepke
                                         Sr. Vice President, Treasurer, and
                                         Chief Accounting Officer
                                         (chief financial officer)