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                                                                   Exhibit 10.18
                                                                     (Form 10-K)

                           CHANGE IN CONTROL AGREEMENT

      This Change in Control Agreement ("Agreement") is made by and between
Citizens Banking Corporation, a Michigan corporation ("Corporation"), and
Randall J. Peterson ("Executive").

      The Corporation anticipates the valuable services that the Executive will
render on behalf of the Corporation and its subsidiary banks and is desirous of
having some assurance that the Executive will continue as an employee and that,
in the event of a possible Change in Control of the Corporation, the Executive
will be able to perform his duties without undue concern for the Executive's
personal financial well-being; and

      The Executive is willing to serve as an employee of the Corporation but
desires assurance that in the event of a Change in Control of the Corporation,
he will continue to have the responsibility and status he has earned.

      Accordingly, the Corporation and the Executive agree as follows:

      1. In order to protect the Executive against the possible consequences of
a Change in Control of the Corporation, as defined in paragraph 2 of this
Agreement, and thereby to induce the Executive to serve as an officer of the
Corporation or a subsidiary bank the Corporation agrees that if (a) there is
such a Change in Control of the Corporation and (b) the Executive's employment
with the Corporation or a subsidiary bank is terminated under the circumstances
described in paragraph 3 of this Agreement, then:

      A. The Corporation shall pay the Executive a lump sum amount in cash equal
to the sum of (i) three times the Executive's annual base salary immediately
prior to the Change in Control (or if higher, the annual base salary on the date
the Executive's employment is terminated) and (ii) three times the greater of
(x) the anticipated bonus amount under the Citizens Banking Corporation
Management Incentive Plan to be earned in accordance with the plan in the year
in which the termination occurs or (y) the highest bonus paid to the Executive
in the last three full calendar years of such employment. The applicable amount
shall be payable within 60 days following the date of the Executive's
termination of employment.

      B. The Executive shall continue to be covered, at the Corporation's cost,
by the medical, dental and life insurance benefit plans that are in effect on
the date of his termination and that cover executive employees, for a period of
thirty-six (36) months after his termination of employment; provided, however,
that if during such time period the Executive should enter into other employment
providing comparable benefits, his participation in such plans of the
Corporation shall cease to the extent of his coverage by his new employer's
plans. Any such non-cash benefit that is tied to compensation shall be based on
the Executive's annual compensation averaged over the same period as applicable
under paragraph A of this Agreement.
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      C. If the Executive was furnished with a club membership, that membership
will be transferred by the Corporation to the Executive at no cost to the
Executive, who immediately following the transfer shall become subject to
monthly dues charges of the club.

      D. All stock options and restricted stock previously granted by the
Corporation to the Executive, whether or not then exercisable, shall become
immediately vested and exercisable.

      E. For a period of one year following termination of the Executive's
employment, the Executive shall be entitled to outplacement services provided by
an outplacement service provider designated by the Corporation. The cost of
providing the outplacement services shall be borne solely by the Corporation,
and shall be equal to the lesser of (i) 10% of the Executive's annual base
salary immediately prior to the Change in Control (or, if higher, the
Executive's annual base salary as of the date of termination of the Executive's
employment) and (ii) $20,000.

      F. If the payment of any of the foregoing amounts or benefits (when added
to any other payments or benefits provided to the Executive in the nature of
compensation) will result in the payment of an excess parachute payment as that
term is defined in Section 280G of the Internal Revenue Code of 1986 ("Code"),
then in such event, the Corporation shall pay the Executive an additional amount
for each calendar year in which an excess parachute payment is received by the
Executive (the "Gross-Up Payment"). The Gross-Up Payment is intended to cover
the Executive's liability for any parachute tax under Code Section 4999 on such
excess parachute payment, as well as federal and state income taxes and
parachute tax on the additional amount, and shall be computed as follows:

            A=Pt/(1 - T - t), where -

            A     is the additional amount for any calendar year;

            P     is the amount of the excess parachute payment for the calendar
                  year in excess of the allocable base amount as defined in Code
                  Section 28OG(b)(3);

            T     is the effective marginal rate of federal and state income tax
                  applicable to the Executive for the calendar year; and

            t     is the rate of parachute tax under Code Section 4999.

            The effective marginal rate of federal and state income tax shall be
            computed as follows:

            T     = F + S(l - 0.8F) + m, where -

            F     is the highest marginal rate of federal income tax applicable
                  to the Executive for the calendar year; and

            S     is the highest aggregate marginal rate of state income tax
                  applicable to the Executive for the calendar year in the state
                  or states and municipalities to


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                  which he is then required to pay income taxes as a result of
                  his employment by the Corporation; and

            m     is the employee's portion of the Medicare tax, currently
                  1.45%.

            Payment of the Gross-Up Payment shall be made to the Executive on or
            before December 31 of each calendar year for which an excess
            parachute payment is received by the Executive.

      G. Subject to the provisions of paragraph G, all determinations required
to be made under these paragraphs E, F and G, including whether and when a
Gross-Up Payment is required and the amount of such Gross-Up Payment and the
assumptions to be utilized in arriving at such determination, shall be made by
Ernst & Young, LLP or such other certified public accounting firm reasonably
acceptable to the Corporation as may be designated by the Executive (the
"Accounting Firm") which shall provide detailed supporting calculations both to
the Corporation and the Executive within 15 business days of the receipt of
notice from the Executive that there has been an excess parachute payment, or
such earlier time as is requested by the Corporation. All fees and expenses of
the Accounting Firm shall be borne solely by the Corporation. Any determination
by the Accounting Firm shall be binding upon the Corporation and the Executive.
As a result of the uncertainty in the application of Section 4999 of the Code at
the time of the initial determination by the Accounting Firm hereunder, it is
possible that Gross-Up Payments which will not have been made by the Corporation
should have been made ("Underpayment"), consistent with the calculations
required to be made hereunder. In the event that the Corporation exhausts its
remedies pursuant to paragraph G and the Executive thereafter is required to
make a payment of any Excise Tax, the Accounting Firm shall determine the amount
of the Underpayment that has occurred and any such Underpayment shall be
promptly paid by the Corporation to or for the benefit of the Executive.

      H. The Executive shall notify the Corporation in writing of any claim by
the Internal Revenue Service that, if successful, would require the payment by
the Corporation of the Gross-Up Payment. Such notification shall be given as
soon as practicable but no later than ten business days after the Executive is
informed in writing of such claim and shall apprise the Corporation of the
nature of such claim and the date on which such claim is requested to be paid.
The Executive shall not pay such claim prior to the expiration of the 30-day
period following the date on which it gives such notice to the Corporation (or
such shorter period ending on the date that any payment of taxes with respect to
such claim is due). If the Corporation notifies the Executive in writing prior
to the expiration of such period that it desires to contest such claim, the
Executive shall: (i) give the Corporation any information reasonably requested
by the Corporation relating to such claim, (ii) take such action in connection
with contesting such claim as the Corporation shall reasonably request in
writing from time to time, including, without limitation, accepting legal
representation with respect to such claim by an attorney reasonably selected by
the Corporation, (iii) cooperate with the Corporation in good faith in order
effectively to contest such claim, and (iv) permit the Corporation to
participate in any proceedings relating to such claim; provided, however, that
the Corporation shall bear and pay directly all costs and expenses (including
additional interest and penalties) incurred in connection with such contest and
shall indemnify and hold the Executive harmless, on an after-tax basis, for any
Excise Tax or income tax (including interest and penalties with respect thereto)
imposed as a result of such


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representation and payment of costs and expenses. Without limitation on the
foregoing provisions of this subparagraph H, the Corporation shall control all
proceedings taken in connection with such contest and, at its sole option, may
pursue or forgo any and all administrative appeals, proceedings, hearings and
conferences with the taxing authority in respect of such claim and may, at its
sole option, either direct the Executive to pay the tax claimed and sue for a
refund or contest the claim in any permissible manner, and the Executive agrees
to prosecute such contest to a determination before any administrative tribunal,
in a court of initial jurisdiction and in one or more appellate courts, as the
Corporation shall determine; provided, however, that if the Corporation directs
the Executive to pay such claim and sue for a refund, the Corporation shall
advance the amount of such payment to the Executive, on an interest-free basis,
and shall indemnify and hold the Executive harmless, on an after-tax basis, from
any Excise Tax and income tax (including interest or penalties with respect
thereto) imposed with respect to such advance or with respect to any imputed
income with respect to such advance calculated as described in subparagraph F of
this section; and further provided that any extension of the statute of
limitations relating to payment of taxes for the taxable year of the Executive
with respect to which such contested amount is claimed to be due is limited
solely to such contested amount. Furthermore, the Corporation's control of the
contest shall be limited to issues with respect to which a Gross-Up Payment
would be payable hereunder and the Executive shall be entitled to settle or
contest, as the case may be, any other issue raised by the Internal Revenue
Service or any other taxing authority. If, after the receipt by the Executive of
an amount advanced by the Corporation pursuant to this subparagraph H, the
Executive becomes entitled to receive any refund with respect to such claim, the
Executive shall (subject to the Corporation's complying with the requirements of
this subparagraph H) promptly pay to the Corporation the amount of such refund
(together with any interest paid or credited thereon after taxes applicable
thereto). If, after the receipt by the Executive of an amount advanced by the
Corporation pursuant to this subparagraph H, a determination is made that the
Executive shall not be entitled to any refund with respect to such claim and the
Corporation does not notify the Executive in writing of its intent to contest
such denial of refund prior to the expiration of 30 days after such
determination, then such advance shall be forgiven and shall not be required to
be repaid and the amount of such advance shall offset, to the extent thereof,
the amount of Gross-Up Payment required to be paid.

      2. For purposes of this Agreement, a "Change in Control" shall mean:

      A. The acquisition by any individual, entity or group (within the meaning
of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act")) (a "Person") of beneficial ownership (within the
meaning of Rule l3d-3 promulgated under the Exchange Act) of 20% or more of
either (1) the then outstanding shares of common stock of the Corporation (the
"Outstanding Corporation Common Stock") or (2) the combined voting power of the
then outstanding voting securities of the Corporation entitled to vote generally
in the election of directors (the "Outstanding Corporation Voting Securities");
provided, however, that for purposes of this subparagraph A, the following
acquisitions shall not constitute a Change in Control: (i) any acquisition
directly from the Corporation, (ii) any acquisition by the Corporation, (iii)
any acquisition by any employee benefit plan (or related trust) sponsored or
maintained by the Corporation or any corporation controlled by the Corporation,
or.(iv) any acquisition by any corporation pursuant to a transaction which
complies with clauses (1), (2) and (3) of subparagraph C of this paragraph 2; or


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      B. Individuals who, as of the date hereof, constitute the Board of
Directors of the Corporation (the "Incumbent Board") cease for any reason to
constitute at least a majority of the Board of Directors; provided, however,
that any individual becoming a director subsequent to the date hereof whose
election, or nomination for election by the Corporation's shareholders, was
approved by a vote of at least a majority of the directors then comprising the
Incumbent Board (either by a specific vote or by approval of the proxy statement
of the Corporation in which such person is named as a nominee for director,
without written objection to such nomination) shall be considered as though such
individual were a member of the Incumbent Board, but excluding, for this
purpose, any such individual whose initial assumption of office occurs as a
result of an actual or threatened election contest with respect to the election
or removal of directors or other actual or threatened solicitation of proxies or
contests by or on behalf of a person other than the Board of Directors of the
Corporation; or

      C. Consummation of a reorganization, merger, share exchange or
consolidation or sale of other disposition of all or substantially all of the
assets of the Corporation (a "Business Combination"), in each case, unless,
following such Business Combination: (1) all or substantially all of the
individuals and entities who were the beneficial owners, respectively, of the
Outstanding Corporation Common Stock and Outstanding Corporation Voting
Securities immediately prior to such Business Combination beneficially own,
directly or indirectly, more than 65% of, respectively, the then outstanding
shares of common stock and the combined voting power of the then outstanding
voting securities entitled to vote generally in the election of directors, as
the case may be, of the corporation resulting from such Business Combination
(including, without limitation, a corporation which as a result of such
transaction owns the Corporation or all or substantially all of the
Corporation's assets either directly or through one or more subsidiaries) in
substantially the same proportions as their ownership, immediately prior to such
Business Combination of the Outstanding Corporation Common Stock and Outstanding
Corporation Voting Securities, as the case may be; (2) no Person (excluding any
corporation resulting from such Business Combination or any employee benefit
plan (or related trust) of the Corporation or such corporation resulting from
the Business Combination) beneficially owns, directly or indirectly, 20% or more
of, respectively, the then outstanding shares of common stock of the corporation
resulting from such Business Combination or the combined voting power of the
then outstanding voting securities of such corporation except to the extent that
such ownership existed prior to the Business Combination; and (3) at least a
majority of the members of the board of directors of the corporation resulting
from such Business Combination were members of the Incumbent Board immediately
prior to the time of the execution of the initial agreement, or of the action of
the Board of Directors of the Corporation, providing for such Business
Combination; or

      D. Approval by the stockholders of the Corporation of a complete
liquidation or dissolution of the Corporation.

      3. Termination of the Executive's employment shall mean the Executive's
termination of employment at any time within 3 months prior to, on the date of,
or within 24 months after a Change in Control of the Corporation as defined in
paragraph 2 of this Agreement either by (a) involuntary dismissal by the
Corporation; or (b) the Executive's constructive termination as described in the
following sentences of this paragraph 3. If (i) there is a significant reduction
in the scope of the Executive's authority or in the extent of his powers,
functions, duties or


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responsibilities, or (ii) the Executive's annual rate of compensation is reduced
or fringe benefits, including relocation benefits, are not provided to him on a
basis commensurate with other executives of the Corporation and its subsidiary
banks, or (iii) there are changes in the Executive's responsibilities for the
Corporation which require moving the Executive's job location to a location
outside of the State of Wisconsin, then the Executive shall be entitled to give
written notice thereof to the Board of Directors of the Corporation. If within
60 days following such notice, the Executive and the Board of Directors of the
Corporation do not resolve the Executive's concerns to the satisfaction of the
Executive (the Executive's satisfaction or dissatisfaction to be communicated to
the Board of Directors of the Corporation in writing within such 60 days), the
Executive's employment shall be deemed to be constructively terminated at the
end of such 60-day period.

      4. The specific arrangements referred to above are not intended to exclude
the Executive's participation in other benefits available to executive personnel
of the Corporation generally or to preclude other compensation or benefits as
may be authorized by the Corporation's Board of Directors from time to time.

      5. As partial consideration for the above, the Executive agrees not to
disclose any confidential information about the Corporation and its operation to
which the Executive was privy during the course of his employment by the
Corporation. Further, the Executive agrees not to accept employment or consult
for or otherwise assist any competitor of the Corporation for a period of 24
months following his termination of employment. For purposes of the foregoing,
"competitor" means any financial institution that conducts business from any
location within 50 miles of any location at which the Corporation or any
subsidiary bank had an office on the day immediately prior to the day on which
the Change of Control of the Corporation occurred.


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      6. This Agreement shall be binding upon and shall inure to the benefit of
the respective successors, assigns, legal representatives and heirs to the
parties.

      7. Any payment or delivery required under this agreement shall be subject
to all requirements of the law with regard to withholding, filing, making of
reports and the like, and the Corporation shall use its best efforts to satisfy
promptly all such requirements.

      8. Notwithstanding anything contained herein to the contrary, this
Agreement shall be terminated and no benefits to the Executive shall be payable
if, at any time, the Executive shall resign voluntarily (other than as provided
in Section 3) , retire at or after normal retirement age, become incapacitated,
voluntarily take another position requiring a substantial portion of his time,
or die. This Agreement also shall terminate upon termination for cause of the
Executive's employment as an officer of the Corporation or any subsidiary bank
by the Incumbent Board. For purposes of the foregoing, "termination for cause"
means termination due to the Executive's conviction of a felony, a determination
that the Executive is guilty of sexual harassment of another employee, the
Executive's proven embezzlement from the Corporation or a subsidiary bank, the
Executive's gross misconduct or incompetence, the Executive's disclosure of
confidential information of the Corporation or intentional assistance of a
competitor of the Corporation (as defined in paragraph 5), or any other activity
of the Executive which has or may have a material adverse effect on the finances
or business reputation of the Corporation or a subsidiary bank.

      9. Any and all disputes, controversies or claims arising out of or in
connection with or relating to this Agreement or any breach or alleged breach
thereof shall, upon the request of either party, be submitted to and settled by
arbitration in the State of Michigan pursuant to the Voluntary Labor Arbitration
Rules, then in effect, of the American Arbitration Association (or at any other
place or under any other form of arbitration mutually acceptable to the parties
involved). The parties hereto specifically agree to arbitrate with the other
party in a proceeding with regard to all issues and disputes, and to permit
pre-hearing discovery in the time and manner provided by the then applicable
Federal Rules of Civil Procedure. This agreement to arbitrate shall be
specifically enforceable under the prevailing arbitration law. Notice of the
demand for arbitration shall be filed, in writing, with the other party to this
Agreement and with the American Arbitration Association. The demand for
arbitration shall be made within a reasonable time after the claim, dispute, or
other matter in question arose where the party asserting the claim should
reasonably have been aware of the same, but in no event later than the
applicable Michigan or federal statute of limitations. The arbitrator shall have
no power to add to, subtract from, or alter the terms of this Agreement, and
shall render a written decision setting forth findings and conclusions only as
to the claims or disputes at issue. Any award by the arbitrator shall be final
and conclusive upon the parties, and a judgement thereon may be entered in the
highest court for the forum, state or federal, having jurisdiction. All expenses
of the arbitration process shall be borne by the Corporation. The Corporation
shall reimburse the Executive for the reasonable fees of legal counsel as
incurred in connection with arbitrating the enforcement of any of the
Executive's rights under this Agreement. However, in no event shall the
Executive be entitled to retain any fees so reimbursed if the claim brought by
the Executive against the


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Corporation is in the arbitrator's sole determination frivolous or was brought
in bad faith, and the Corporation will be entitled to seek repayment from the
Executive for such fees after such determination by the arbitrator.

      10. The invalidity or unenforceability of any provision of this Agreement
shall not affect the enforceability or validity of any other provision hereof.

      11. This Agreement constitutes the entire agreement of the parties with
respect to the subject matter addressed in this Agreement. This Agreement may be
amended only in a written document signed by both the Corporation and the
Executive.

      12. This Agreement shall be governed by the laws of the State of Michigan.
This Agreement has been executed by the parties effective as of April 7, 2003.

CITIZENS BANKING CORPORATION          EXECUTIVE


By:
      ----------------------------    --------------------
        William R. Hartman            Randall J. Peterson
        Chairman, President and
        Chief Executive Officer

Date: April 7, 2003                   Date: April 7, 2003


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