ISABELLA BANK CORPORATION RETIREMENT BONUS PLAN

Exhibit 10.1 ISABELLA BANK CORPORATION RETIREMENT BONUS PLAN July 1, 2008

TABLE OF CONTENTS

ISABELLA BANK CORPORATION RETIREMENT BONUS PLAN      Isabella Bank Corporation (Isabella) established a nonqualified plan of deferred compensation benefits for its eligible employees effective January 1, 2007, pursuant to Section 409A of the Internal Revenue Code. The Plan is intended to postpone taxation of such deferred compensation benefits until those benefits are paid to the employees as provided in the Plan. The provisions of this Plan are hereby restated on and after July 1, 2008, as set forth below. Section 1. Purpose .      The Plan is intended to provide eligible employees with additional compensation, payable as set forth in the Plan, in order to reward the individuals who contribute to the success of Company. Section 2. Definitions .      The following words and phrases shall, when used in this Plan, have the meanings set forth below unless their context clearly indicates otherwise:      2.01 Administrator or Plan Administrator means Isabella which may, from time to time in its sole discretion, appoint a person or persons to assist in the administration of the Plan.      2.02 Allocation Date means March 31, June 30, September 30 or December 31 of each Plan Year.      2.03 Board of Directors means Company’s governing body according to law and Company’s governing documents.      2.04 Change of Control means a sale which results in a change in the ownership of Company, a change in the effective control of Company, or a change in the ownership of a substantial portion of Company’s assets. The change shall not be deemed a "Change of Control" for purposes of this Plan unless the change (whether made in a single transaction or in successive multiple transactions) effectively transfers the controlling interest of Company to an unrelated third party(ies) (as defined under the attribution rules of Code Sections 318 and 414) and said change results in the unrelated third party(ies) owning more than fifty percent (50%) of the fair market value or the total voting power of the stock of Company. In addition to the foregoing, the Change of Control must satisfy the provisions of Q & A-11 through 14 of IRS Notice 2005-1 and IRS. Reg. 1.409A-3(i)(5) and subsequent guidance.      2.05 Code means the Internal Revenue Code of 1986, as amended.

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     2.06 Committee or Administrative Committee means the committee described in Section 15.      2.07 Company means Isabella Bank Corporation, Isabella Bank or their respective successor or successors, and any other entity whose Board of Directors authorizes participation in this Plan where Isabella by its Board of Directors has approved such participation.      2.08 Deferred Compensation Account or Account means the bookkeeping account maintained on behalf of Participant to record Company contributions made pursuant to Section 4.01.      2.09 Disability means Participant is:           (a) unable to engage in any substantial gainful activity by reason of any medically determinable or physical or mental impairment which can be expected to result in death or can be expected to last for a continuous period of not less than 12 months, or           (b) by reason of any medically determinable or physical or mental impairment which can be expected to result in death or can be expected to last for a continuous period of not less than 12 months, receiving income replacement benefits for a period of not less than three months under an accident and health plan covering Employees of Company.      2.10 Early Retirement Age means Participant’s attainment of age 55.      2.11 Effective Date means July 1, 2008, the date on which the provisions of this restated Plan become effective.      2.12 Employee means an individual who is employed by Company on January 1, 2007, and who is a participant in Company’s frozen Executive Supplemental Income Agreement, provided the individual is an officer of Company and has completed at least ten (10) years of service with Company as of December 31, 2006. Company has sole and exclusive discretion to add new Participants to the Plan by authorizing such participation pursuant to action of Company’s Board of Directors.      2.13 Just Cause means that Company has determined in its sole and exclusive discretion that Participant has engaged in theft, fraud, embezzlement or willful misconduct. In the event Participant is discharged for Just Cause, Participant agrees to consent to the revocation of the benefit payable under the Plan. In the event of such revocation, this Plan shall be null and void with respect to the affected Participant, and the Participant shall not have a claim under the Plan against Company.      2.14 Normal Retirement Age means Participant’s attainment of age 65.      2.15 Participant means an Employee who participates in the Plan.      2.16 Plan means the Isabella Bank Corporation Retirement Bonus Plan, as amended from time to time.

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     2.17 Plan Year means the consecutive 12-month period beginning on January 1 and ending on December 31.      2.18 Retirement means, with respect to a Participant, severance from service with Company for any reason on or after the attainment of Early Retirement Age; provided, however, with respect to a Participant who is entitled to a distribution on account of Participant’s Disability or Separation From Service, Retirement means the later of attainment of Early Retirement Age or Participant’s actual severance date.      2.19 Separation From Service means Participant’s severance of employment with Company either voluntarily or involuntarily without Just Cause, within the 30-day period preceding or the 12-month period following a Change of Control.      2.20 Similar Arrangement means an agreement, method, program or other arrangement sponsored by the Company with respect to which deferrals are treated as having been deferred under a single plan under IRS Reg. 1.409A-1(c)(2). Section 3. Participation/Establishment of Accounts .      3.01 Initial Participation . Any individual who was an eligible Employee on January 1, 2007, commenced participation in the Plan on said date.      3.02 Subsequent Participation . Any individual who becomes eligible to participate in the Plan after the Effective Date shall commence participation in the Plan on the date the Committee determines, in its sole discretion.      3.03 Accounts . Company agrees to create a Deferred Compensation Account to be maintained on the books of Company in the name of each Participant, as described in Section 4 below. Section 4. Allocations to Account .      4.01 Company Contributions . Each Participant who commences participation in the Plan on January 1, 2007, had an initial amount credited to his Deferred Compensation Account on said date. Subsequent amounts shall be credited to Participant’s Deferred Compensation Account on each Allocation Date thereafter. The amount of the initial allocation and Participant’s annual allocation shall be determined pursuant to a payment schedule adopted in the sole and exclusive discretion of the Board of Directors, as set forth in the Addendum to this Plan, as amended from time to time. Following the initial allocation, one-fourth (1/4) of each annual allocation shall be credited to Participant’s Deferred Compensation Account on the applicable Allocation Date, provided Participant is employed by Company on the Allocation Date.      4.02 Earnings Allocation . Subject to Section 10, amounts credited to Participant’s Deferred Compensation Account shall be adjusted on each Allocation Date for earnings as described in this Section 4.02. Such adjustments shall continue quarterly until the date when all benefits payable under the Plan have been distributed to Participant. The income allocated to

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Participant’s Deferred Compensation Account shall be the mid-term applicable federal rate (as defined in Code Section 1274(d)) for January 1 of the calendar year in which the income is credited, such interest to be compounded annually.      Company does not guarantee the preservation of the principal amount credited to Participant’s Account or a minimum rate of return on any such investments. Section 5. Vesting .      Subject to satisfying the distribution events set forth in Section 6 below, Participant’s interest in his Deferred Compensation Account shall be 100% vested and nonforfeitable upon the first to occur of a Participant’s Retirement, Separation From Service or experiencing a Disability. Notwithstanding the provisions of Section 4.01, in the event of Participant’s Separation From Service or Disability, Participant’s interest in his Deferred Compensation Account balance shall be the amount he would have received at Early Retirement Age had he continued to participate in the Plan and retired upon reaching Early Retirement Age; provided, however, if the Participant elects a delayed distribution date (not to exceed the Participant’s attainment of Normal Retirement Age), in accordance with Section 6.02, Participant’s vested interest in his Deferred Compensation Account shall be the amount he would have received on the delayed distribution date had he continued to participate in the Plan and retired on the delayed distribution date. Section 6. Commencement of Distribution .      6.01 Distribution Dates . The form and manner in which distributions will be made from the Plan shall be determined in accordance with Section 7 below. No amount standing from time to time to the credit of Participant in his Deferred Compensation Account shall be assignable or alienable by Participant, nor may any such payment be used as collateral or in any other fashion by Participant prior to payment by Company. Subject to Section 6.03 below, no amount standing from time to time to the credit of Participant in his Deferred Compensation Account shall be payable to Participant until the earliest of the following distribution dates:           (a) Participant’s Retirement date;           (b) The date of Participant’s Separation From Service; or           (c) The date of Participant’s termination of employment on account of his Disability.      6.02 Time of Distribution . When the amounts credited to Participant’s Deferred Compensation Account become payable pursuant to Section 6.01 (a) or (b) above, distribution of such benefit shall begin on the first day of the seventh month after the first Allocation Date that immediately follows the earliest distribution date, or as soon as administratively practicable thereafter. Distribution of a benefit payable pursuant to Section 6.01(c) above shall begin on the first day of the first month after the Allocation Date that immediately follows the event, or as soon as administratively possible thereafter.

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          Notwithstanding the foregoing, Participant may elect a delayed distribution date. The delayed distribution date may be a specific future date or the attainment of a specified age by the Participant (not to exceed the Participant’s attainment of age 65), so long as the delayed distribution date is:           (a) requested at least twelve (12) months prior to the earliest distribution date;           (b) the election does not take effect until at least twelve (12) months after the date on which the election is made; and           (c) the payment is postponed for a period of not less than five (5) years from the date the payment would otherwise have been made.      6.03 Accelerating the Time of Payment . Notwithstanding the distribution dates set forth in Section 6.01 above, an early distribution may be made as soon as administratively possible in accordance with IRS Reg. 1.409A-3(j)(4) and subsequent guidance following the occurrence of any of the following events :           (a) to fulfill the requirements of a domestic relations order;           (b) as necessary to comply with a certificate of divestiture as defined in Code Section 1043(b)(2);           (c) to make payment of certain employment and/or income taxes;           (d) de minimis cashout amounts not exceeding $10,000; or           (e) certain arrangement terminations of the Plan as described in Section 11 below.      In the case of an accelerated payment due to Section 6.03(a) above, a payment under the Plan may be made to an individual other than the Participant to the extent necessary to fulfill the terms of a domestic relations order that is issued by a court of competent jurisdiction. The Plan’s rules regarding changes in the time and form of payment do not apply to changes in the time and form of payment that are required by such a domestic relations order, so long as the payment that is made pursuant to the domestic relations order will be made to the alternate payee who is named in the domestic relations order and not to the Participant. The Plan will make such a payment at the time and in the form specified in the domestic relations order. If the domestic relations order requires that the alternate payee be given an election as to the time and form of payment, the Plan will follow such an alternate payee’s election of a time and form of payment so long as the alternate payee makes said election in accordance with the Plan’s rules and procedures relating to time and form of payment elections. The Plan may make such a payment to someone other than a Participant pursuant to a domestic relations order only with regard to deferrals resulting from Compensation paid for services that were rendered after December 31, 2004, and investment gains and losses thereon. The Participant to whom the domestic relations order relates must pay to the Company whatever amount is charged by the Company for processing the domestic relations order and making the payment to someone other than the

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Participant. This payment to the Company cannot be deducted from the amount credited to the Participant’s Plan Account.      6.04 Delaying Payments Under Certain Circumstances . A payment may be delayed