<SEC-DOCUMENT>0000860413-20-000096.txt : 20200318
<SEC-HEADER>0000860413-20-000096.hdr.sgml : 20200318
<ACCEPTANCE-DATETIME>20200318153327
ACCESSION NUMBER:		0000860413-20-000096
CONFORMED SUBMISSION TYPE:	POS AM
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20200318
DATE AS OF CHANGE:		20200318

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRST INTERSTATE BANCSYSTEM INC
		CENTRAL INDEX KEY:			0000860413
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				810331430
		STATE OF INCORPORATION:			MT
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		POS AM
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-220594
		FILM NUMBER:		20724214

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 30918
		STREET 2:		401 NO 31ST STREET
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116-0918
		BUSINESS PHONE:		4062555300

	MAIL ADDRESS:	
		STREET 1:		P O BOX 30918
		STREET 2:		401 NO 31ST STREET
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116-0918

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST INTERSTATE BANCSYSTEM OF MONTANA INC
		DATE OF NAME CHANGE:	19930615
</SEC-HEADER>
<DOCUMENT>
<TYPE>POS AM
<SEQUENCE>1
<FILENAME>fibk-20200318xposam1.htm
<DESCRIPTION>POS AM
<TEXT>
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<div><a name="s093890F4A4AF51CCB6D3154F7A80E878"></a></div><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><div><br></div><div style="line-height:120%;text-align:center;text-indent:48px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">As filed with the Securities and Exchange Commission on March 18, 2020</font></div><div style="line-height:120%;text-align:right;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Registration No. 333-220594</font></div><div style="line-height:120%;padding-top:4px;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="1"></td></tr><tr><td style="width:100%;"></td></tr><tr><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr></table></div></div><div style="line-height:120%;padding-top:8px;text-align:center;font-size:12pt;"><font style="font-family:inherit;font-size:12pt;font-weight:bold;">UNITED STATES</font></div><div style="line-height:120%;text-align:center;font-size:12pt;"><font style="font-family:inherit;font-size:12pt;font-weight:bold;">SECURITIES AND EXCHANGE COMMISSION</font></div><div style="line-height:120%;padding-bottom:8px;text-align:center;font-size:12pt;"><font style="font-family:inherit;font-size:12pt;font-weight:bold;">Washington, D.C. 20549</font><font style="font-family:inherit;font-size:8pt;">&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;&#32;</font></div><div style="line-height:120%;text-align:center;font-size:13pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td style="width:29%;"></td><td style="width:42%;"></td><td style="width:29%;"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">POST-EFFECTIVE AMENDMENT NO. 1 TO</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:13pt;"><font style="font-family:inherit;font-size:13pt;font-weight:bold;">Form S-3</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">REGISTRATION STATEMENT UNDER</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">THE SECURITIES ACT OF 1933</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr></table></div></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;"><br></font></div><div style="line-height:120%;padding-bottom:8px;text-align:center;font-size:18pt;"><font style="font-family:inherit;font-size:18pt;font-weight:bold;">First Interstate BancSystem, Inc.</font></div><div style="line-height:120%;padding-bottom:8px;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">(Exact name of registrant as specified in its charter)</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:78.90625%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td style="width:37%;"></td><td style="width:27%;"></td><td style="width:36%;"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Montana</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">81-0331430</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">(State or other jurisdiction of</font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">incorporation or organization)</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">(I.R.S. Employer</font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">Identification Number)</font></div></td></tr></table></div></div><div style="line-height:120%;padding-top:8px;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">401 North 31st Street</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Billings, Montana 59116</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">(406) 255-5390</font></div><div style="line-height:120%;padding-bottom:8px;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">(Address, including zip code and telephone number, including area code, of registrant&#8217;s principal executive offices)</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Marcy D. Mutch</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Executive Vice President and Chief Financial Officer</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">401 North 31st Street</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Billings, Montana 59116</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">(406) 255-5390</font></div><div style="line-height:120%;text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;">(Name, address, including zip code and telephone number, including area code, of agent for service)</font></div><div style="line-height:120%;padding-bottom:2px;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td style="width:29%;"></td><td style="width:42%;"></td><td style="width:29%;"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-style:italic;font-weight:bold;">Copies to:</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:8px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:8px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:8px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Scott A. Berdan, Esq.</font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Kevin L. Vold, Esq.</font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Polsinelli PC</font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">1401 Lawrence Street, Suite 2300 </font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Denver, CO 80202 </font></div><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">(303) 572-9300</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr></table></div></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Approximate date of commencement of proposed sale to the public:</font><font style="font-family:inherit;font-size:8pt;">&#32;&#32;Not applicable</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If this form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If this form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;padding-bottom:2px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of &#8220;large accelerated filer,&#8221; &#8220;accelerated filer,&#8221; &#8220;smaller reporting company,&#8221; and &#8220;emerging growth company&#8221; in Rule&#160;12b-2 of the Exchange Act.</font></div><div style="line-height:120%;padding-bottom:2px;text-align:center;text-indent:18px;font-size:8pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="5"></td></tr><tr><td style="width:19%;"></td><td style="width:17%;"></td><td style="width:19%;"></td><td style="width:22%;"></td><td style="width:23%;"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Large accelerated filer&#160; </font><font style="font-family:Wingdings;font-size:8pt;">&#253;</font><font style="font-family:inherit;font-size:8pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Accelerated filer &#160;</font><font style="font-family:Wingdings;font-size:8pt;">o</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Non-accelerated filer&#160; </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Smaller reporting  company&#160;</font><font style="font-family:Wingdings;font-size:8pt;">o</font><font style="font-family:inherit;font-size:8pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">Emerging growth company&#160;</font><font style="font-family:Wingdings;font-size:8pt;">o</font><font style="font-family:inherit;font-size:8pt;">&#160;</font></div></td></tr></table></div></div><div style="line-height:120%;padding-bottom:2px;padding-top:8px;text-align:justify;text-indent:24px;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  </font><font style="font-family:Wingdings;font-size:8pt;">o</font></div><div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div><br></div><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><div><br></div><div style="line-height:120%;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">DEREGISTRATION OF SECURITIES</font></div><div style="line-height:120%;text-align:center;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">This Post-Effective Amendment No. 1 relates to the Registration Statement on Form S-3 (File No. 333-220594) of First Interstate BancSystem, Inc. (the &#8220;Registrant&#8221;), which was filed with the Securities and Exchange Commission on September 22, 2017 and became effective on October 3, 2017 (the &#8220;Registration Statement&#8221;).  The Registration Statement registered shares of the Registrant's Class A common stock with an aggregate offering price not more than $250,000,000.  </font></div><div style="line-height:120%;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In accordance with the Registrant&#8217;s undertakings in the Registration Statement, the Registrant hereby deregisters by means of this post-effective amendment any securities remaining unsold under the Registration Statement as of the date hereof and withdraws the Registration Statement.</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">SIGNATURES</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;padding-bottom:13px;text-align:left;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Billings, State of Montana, on March 18, 2020. </font></div><div style="line-height:120%;text-align:justify;font-size:1pt;"><font style="font-family:inherit;font-size:1pt;">&#160;</font></div><div style="line-height:120%;text-align:center;font-size:11pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:99.609375%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td style="width:48%;"></td><td style="width:5%;"></td><td style="width:47%;"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td colspan="2" style="vertical-align:top;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:11pt;"><font style="font-family:inherit;font-size:11pt;">FIRST INTERSTATE BANCSYSTEM, INC.</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:top;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:11pt;"><font style="font-family:inherit;font-size:11pt;">By:</font></div></td><td style="vertical-align:top;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:11pt;"><font style="font-family:inherit;font-size:11pt;">/s/ MARCY D. MUTCH</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:top;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:11pt;"><font style="font-family:inherit;font-size:11pt;">Marcy D. Mutch</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:11pt;"><font style="font-family:inherit;font-size:11pt;">Executive Vice President and Chief Financial Officer</font></div></td></tr></table></div></div><div style="line-height:120%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:justify;padding-left:288px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;padding-left:288px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div><br></div><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div>	</div></body>
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