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                                  EXHIBIT 4.26

                             SHAREHOLDER'S AGREEMENT

         THIS AGREEMENT is made this _____ day of __________, 2001, by and
between __________________, herein referred to as "Shareholder", and FIRST
INTERSTATE BANCSYSTEM, INC., a Montana corporation, 401 North 31st Street,
Billings, Montana 59101, herein referred to as the "Corporation".

                              W I T N E S S E T H :

     A. Shareholder owns capital stock of the Corporation, which together with
any additional stock hereafter acquired by Shareholder, is referred to herein as
the "Stock".

     B. The Corporation desires to restrict the issuance and holding of its
corporate stock to officers, directors, including advisory directors and any
other classification or designation of directors hereafter made by the
Corporation and employees of the Corporation or any of its subsidiaries, and to
fiduciaries for the benefit of any such persons, to charities, and to such other
persons as the Corporation may permit. This Shareholder's Agreement does not
apply to the Corporation's stock held in the Savings Plan.

     C. The Corporation and Shareholder make this Agreement to set forth the
restrictions on the Stock.

     NOW, THEREFORE, in consideration of the above facts and the Shareholder's
and the Corporation's mutual promises herein, the Shareholder and the
Corporation agree as follows:

     1. RESTRICTION ON TRANSFER OR PLEDGE OF STOCK. Except as otherwise provided
in this Agreement or as agreed upon in writing by the Shareholder and the
Corporation, Shareholder shall not transfer or permit to be transferred, whether
voluntarily, involuntarily or by operation of law, resulting from death or
otherwise, any or all of the Stock, and any attempted transfer in violation of
this Agreement shall be void. Shareholder shall not encumber or use any Stock as
security for a loan, except upon the written consent of the Corporation. Under
no circumstances, including but not limited to the provisions of paragraph 2
below, may a Shareholder who has acquired Stock under the First Interstate
BancSystem, Inc. 2001 Stock Option Plan or any other plan hereafter adopted by
the Corporation (the "Plan") transfer, attempt to transfer, or permit the
transfer of any of the Stock so acquired for a period of six (6) months
following the date of acquisition of such Stock. If the Corporation agrees in
writing to a transfer of Stock pursuant to this paragraph, the Stock shall be
transferred subject to the terms, conditions and limitations of this Agreement
and the certificate for the Stock shall contain the restrictive legend provided
in this Agreement, unless otherwise agreed in writing by the Corporation.

     2. TRANSFER OF STOCK TO CHARITY. A Shareholder may transfer Stock to any
organization described in Section 170(b)(1)(A) of the Internal Revenue Code of
1986, as now or hereafter amended (the "Code"), a gift to which qualifies as a
charitable deduction under Sections 170(c), 2055(a), or 2522(a) of the Code (a
"Charity"). Stock transferred to a Charity shall be subject to the terms of this
Agreement, and the certificate issued to the Charity for the Stock shall contain
the legend required by this Agreement.

     3. CORPORATION STOCK PURCHASE RIGHTS.

     3.1 RIGHT OF FIRST REFUSAL. If a Shareholder desires to transfer any Stock,
Shareholder shall give written notice of such desire to the Corporation in the
form of Exhibit A attached hereto. Within one hundred eighty (180) days after
the Corporation's receipt of the notice, the Corporation may exercise its right
to purchase all but not less than all of the Stock desired to be transferred by
Shareholder upon the terms set forth in this Agreement.



Shareholder's Agreement
August 24, 2001

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     3.2 GENERAL REPURCHASE RIGHT. The Corporation shall have the right, but not
the obligation, to repurchase some or all of Shareholder's Stock on the terms
set forth in this Agreement at any time prior to the date on which the
Corporation's common stock is offered for sale to the public following
successful registration of the common stock with the Securities and Exchange
Commission and after the expiration of a six (6) month holding period measured
from the date of the Shareholder's acquisition of Shares through exercising an
option under the Plan,

     4. EXERCISE OF PURCHASE RIGHT. The Corporation shall exercise any purchase
right granted in this Agreement by delivering written notice of its exercise of
the purchase right, within any time period required hereunder, to the
Shareholder, or to the personal representative of Shareholder's estate if the
Shareholder is deceased.

     5. EFFECT OF NON-EXERCISE OF PURCHASE RIGHT. If any purchase right is
forfeited or is not exercised in compliance with the terms of this Agreement,
then the Stock to which such purchase right applied shall be unrestricted and no
longer subject to the terms of this Agreement.

     6. PURCHASE PRICE FOR SHARES.

     6.1 DETERMINATION OF PURCHASE PRICE. The purchase price for each share of
Stock purchased pursuant to any of the purchase rights granted in this Agreement
shall be the Fair Market Value of the Stock . "Fair Market Value" means, as of
any date, the value of a share of Stock determined as follows:

          (i)  If the Stock is listed on any established stock exchange or a
               national market system, its Fair Market Value shall be the
               closing sales price for the Stock (or the closing bid, if no
               sales were reported) as quoted on such exchange or system for the
               last market trading day prior to the date of determination, as
               reported in The Wall Street Journal or such other sources as the
               Corporation's board of directors (the "Board") deems reliable;

          (ii) If the Stock is regularly quoted by a recognized securities
               dealer but selling prices are not reported, its Fair Market Value
               shall be the mean between the high bid and the low asked prices
               for the Stock on the last market trading day prior to the date of
               determination; or

          (iii) In the absence of an established market for the Stock, its Fair
               Market Value thereof shall be determined in good faith by the
               Board which may, in its sole discretion, utilize an independent
               third party to assist with the determination of the Fair Market
               Value of the Stock, which may take the form of a periodic
               appraisal of the Fair Market Value of a share of Stock valued as
               a minority interest.

     6.2 PAYMENT OF THE PURCHASE PRICE. The purchase price for Stock to be
purchased by the Corporation pursuant to this Agreement shall be paid in cash at
the closing of the purchase of the Stock. The Corporation may, at its option,
withhold any amount that the Shareholder owes the Corporation or its
subsidiaries from the amount of the purchase price payable to Shareholder and
apply said amount to such indebtedness.



Shareholder's Agreement
August 24, 2001

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     7. THE CLOSING.

     7.1 TIME AND PLACE. Unless otherwise agreed by the parties, the closing of
the sale and purchase of Stock, as provided in this Agreement, shall take place
at the general offices of the Corporation within thirty (30) days after the
Corporation's exercise of its right to purchase the Shareholder's Stock.

     7.2 DOCUMENTS. At the closing of the sale and purchase of the Stock, the
Corporation and the Shareholder or other party having an interest in the Stock
being purchased hereunder shall execute and immediately deliver to each other
the various documents which shall be required to carry out their undertakings
hereunder, including but not limited to the payment of cash and the assignment
and delivery of stock certificates free and clear of all taxes, debts, claims,
judgments, liens or encumbrances whatsoever.

     8. LEGEND ON CERTIFICATES. Certificates representing the Stock shall bear
the following legend reciting the existence of this Agreement and restrictions
on transfer of the Stock:

          The sale, transfer or encumbrance of the shares of stock represented
          by this certificate is subject to an agreement to restrict transfer or
          acquisition of the shares. A copy of the agreement is on file in the
          office of the secretary of the Corporation. Any transfer or
          acquisition in violation of the agreement is null and void.

     9. REISSUED STOCK. The Corporation shall have the right to substitute or
reissue stock in exchange for the Stock in the event of a stock split, merger,
consolidation, name change, sale, spin off, share exchange, or other corporate
reorganization. Substituted or reissued stock shall be subject to the terms of
this Agreement.

     10. TERMINATION.

     10.1 EVENTS CAUSING TERMINATION. This Agreement and all restrictions on
stock created hereby shall be effective as of the date hereof and shall
terminate on the occurrence of the bankruptcy, receivership or dissolution of
the Corporation, on the public trading of the Stock, or on the execution of a
written instrument by the Corporation and the party or parties who then own
Stock subject to this Agreement which terminates the same.

     10.2 SURVIVAL OF RIGHTS AND REMEDIES. The termination of this Agreement for
any reason shall not affect any right or remedy existing hereunder prior to the
effective date of termination hereof.

     11. GENERAL PROVISIONS.

     11.1 REMEDIES. The parties agree that they will not have an adequate remedy
at law for the breach of this Agreement because, among other reasons, the Stock
cannot readily be purchased or sold on the open market. The parties shall have
available for any breach of this Agreement the remedies of specific performance
and injunctive relief, together with all other remedies at law or in equity. No
waiver of or forbearance to enforce any right or provision hereof shall be
binding unless in writing and signed by the party to be bound, and no such
waiver or forbearance in any instance shall apply to any other instance or any
other right or provision.



Shareholder's Agreement
August 24, 2001

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     11.2 MODIFICATION OR TERMINATION. This Agreement may not be modified or
terminated orally, and no modification, termination, or amendment shall be valid
unless in writing signed by all parties hereto.

     11.3 GOVERNING LAW. This Agreement shall be governed for all purposes by
the laws of the State of Montana.

     11.4 SEVERABILITY. Each term and provision of this Agreement is intended to
be enforced to the maximum extent permitted by applicable law. If any term or
provision of this Agreement or the applicability thereof to any person or
circumstances shall to any extent be invalid or unenforceable, the remainder of
this Agreement, or the application of such term or provision to persons or
circumstances other than those as to which it is held invalid or unenforceable,
shall not be affected thereby and shall continue in full force and effect.

     11.5 NOTICES. All notices provided for by this Agreement shall be made in
writing and shall be given either: (1) by actual delivery of the notice to the
party entitled thereto; or (2) by mailing the notice in the U.S. mails,
certified mail, return receipt requested to the last known address of the party
entitled thereto. The notice shall be deemed to be received in case (1) on the
date of its actual receipt by a party and in case (2) on the date of its
mailing.

     11.6 BINDING EFFECT. This Agreement is binding upon and inures to the
benefit of the Corporation and the Shareholder and their respective heirs, legal
representatives, successors and assigns.

     11.7 TIME. Time shall be of the essence of this Agreement.

     11.8 HEADINGS. The headings used herein are for convenience only, and shall
not be construed as a part of this Agreement or as a limitation on the scope of
the particular paragraphs to which they refer.

     11.9 ENTIRE AGREEMENT. This Agreement contains the entire agreement and
understanding of the parties, and supersedes any and all prior negotiations,
understandings, and agreements.

     IN WITNESS WHEREOF, the parties have executed this Agreement on the date
set forth on page 1.

                                       FIRST INTERSTATE BANCSYSTEM,
                                       INC.

                                       By
                                            ------------------------------------

                                       Its:
                                            ------------------------------------

                                                                  "Corporation"

                                            ------------------------------------

                                                                  "Shareholder"


Shareholder's Agreement
August 24, 2001

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                                    EXHIBIT A

                                     NOTICE


To:  First Interstate BancSystem, Inc.
     401 North 31st Street
     Billings, MT  59101

     Pursuant to the Shareholder's Agreement between the undersigned Shareholder
     and First Interstate BancSystem, Inc. ("Corporation"), the undersigned
     hereby gives notice of Shareholder's desire to sell _____ shares of
     Corporation common stock to the Corporation pursuant to the terms of the
     Shareholder's Agreement.




Dated: _________________________, 20____.


                                              ----------------------------------
                                              Shareholder




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