Exhibit 32.1
                                                                     (Form 10-K)

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350
          AND RULE 13A-14(B) UNDER THE SECURITIES EXCHANGE ACT OF 1934

In connection with the Annual Report of Citizens Banking Corporation
("Citizens") on Form 10-K for the period ending December 31, 2003 as filed with
the Securities and Exchange Commission on the date hereof (the "Report"), I,
William R. Hartman, Chief Executive Officer of the Company, certify, pursuant to
18 U.S.C. Section 1350 and Rule 13a-14(b) under the Securities Exchange Act of
1934, that:

(1)  The Report fully complies with the requirements of Section 13(a) 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 Citizens.

Dated: March 15, 2004


                                /s/ William R. Hartman
                                --------------------------------------------
                                William R. Hartman
                                Chairman, President and Chief Executive Officer