Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Huston Michael G.
  2. Issuer Name and Ticker or Trading Symbol
FIRST INTERSTATE BANCSYSTEM INC [FIBK]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Ex. VP & Chief Banking Officer
(Last)
(First)
(Middle)
PO BOX 30918
3. Date of Earliest Transaction (Month/Day/Year)
08/28/2015
(Street)

BILLINGS, MT 59116
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Class A Common Stock               4,972 I By 401(k) Plan
Class A Common Stock 08/28/2015   J(1)   804 D $ 0 8,636 D  
Class A Common Stock 08/28/2015   J(1)   804 A $ 0 16,996 I By Trust
Class A Common Stock 08/31/2015   C   1,776 A $ 0 1,776 I By IRA
Class A Common Stock 08/31/2015   M   800 A $ 17 9,436 D  
Class A Common Stock 08/31/2015   S   800 D $ 26.5125 (2) 8,636 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Class B Common Stock (3) $ 0 08/31/2015   C     1,776 03/05/2010 12/31/2029(3) Class A Common Stock (3) 1,776 $ 0 0 I By IRA
Stock Options $ 17 08/31/2015   M     800 01/26/2006 01/26/2016 Class B Common Stock (4) 800 $ 17 1,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Huston Michael G.
PO BOX 30918
BILLINGS, MT 59116
      Ex. VP & Chief Banking Officer  

Signatures

 /s/ CAROL DONALDSON, Attorney-in-Fact for Reporting Person   09/01/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Change in form of beneficial ownership from direct ownership to indirect ownership by trust.
(2) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $26.51 to $26.53. Reporting Person undertakes to provide to First Interstate BancSystem, Inc., any security holder of First Interstate BancSystem, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding number of shares purchased at each separate price within the range set forth in this Form 4.
(3) The Class B Common Stock is convertible at any time into Class A Common Stock on a share for share basis at the descretion of the holder. The conversion feature of the Class B common stock does not expire.
(4) Simultaneous with exercise of stock options, an election was made to immediately convert Class B commons shares received to Class A common shares.

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