Exhibit 23
                                                                     (Form 10-K)


               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS



We consent to the incorporation by reference in (1) the Registration Statement
(Form S-8 No. 33-47686 dated May 5, 1992) pertaining to the Citizens Banking
Corporation Second Amended Stock Option Plan; (2) the Registration Statement
(Form S-8 No. 333-09455 dated August 2, 1996) pertaining to the Citizens Banking
Corporation Amended and Restated Section 401(k) Plan; (3) the Registration
Statement (Post Effective Amendment No. 1 to Form S-4 on Form S-8 No. 333-86569
dated December 22, 1999) pertaining to the F&M Bancorporation, Inc. stock option
plans; (4) the Registration Statement (Form S-8 No. 333-40100 dated June 26,
2000) pertaining to the Citizens Banking Corporation All Employee Stock Option
Plan; (5) the Registration Statement (Form S-8 No. 333-86326 dated April 16,
2002) pertaining to Citizens Banking Corporation Stock Compensation Plan, and
(6) the Registration Statement (Post Effective Amendment No. 1 to Form S-8 No.
33-61197 dated February 24, 2003) pertaining to the Citizens Banking Corporation
Stock Option Plan for Directors; of our report dated January 16, 2003, with
respect to the consolidated financial statements of Citizens Banking Corporation
incorporated by reference in the Annual Report (Form 10-K) for the year ended
December 31, 2002.


/s/ Ernst & Young LLP
- ---------------------
Ernst & Young LLP

Detroit, Michigan
March 25, 2003