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<title>Document</title></head><body><div id="i70ac8497212b4c4dbe2951960fe714b8_1"></div><div style="min-height:42.75pt;width:100%"><div><font><br></font></div></div><div style="text-align:center;text-indent:36pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">As filed with the Securities and Exchange Commission on May 23, 2024</font></div><div style="text-align:right"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Registration No 333-</font><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:98.900%"></td><td style="width:0.1%"></td></tr><tr style="height:3pt"><td colspan="3" style="border-bottom:3pt double #000000;padding:0 1pt"></td></tr></table></div><div style="margin-top:6pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:120%">UNITED STATES</font></div><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:120%">SECURITIES AND EXCHANGE COMMISSION</font></div><div style="margin-bottom:6pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:120%">Washington, D.C. 20549</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">                </font></div><div style="margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:27.951%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:40.797%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:27.952%"></td><td style="width:0.1%"></td></tr><tr style="height:3pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="9" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">FORM S-8</font></td></tr><tr style="height:12pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="9" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933</font></td></tr><tr style="height:3pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr></table></div><div style="text-align:center"><font><br></font></div><div style="margin-bottom:2pt;margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:32.233%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:32.233%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:32.234%"></td><td style="width:0.1%"></td></tr><tr><td colspan="9" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-bottom:2pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:18pt;font-weight:700;line-height:100%">First Interstate BancSystem, Inc.</font></div></td></tr><tr><td colspan="9" style="border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-bottom:6pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(Exact name of registrant as specified in its charter)</font></div></td></tr></table></div><div style="margin-bottom:6pt;text-align:center"><font><br></font></div><div style="margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:96.783%"><tr><td style="width:1.0%"></td><td style="width:36.362%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:23.975%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:36.363%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Delaware</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">81-0331430</font></td></tr><tr><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(State or other jurisdiction of incorporation or organization)</font></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(I.R.S. Employer Identification Number)</font></td></tr><tr style="height:8pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-top:6pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">401 North 31st Street, Billings, Montana</font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">59101</font></td></tr><tr><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(Address of principal executive offices)</font></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(Zip Code)</font></td></tr></table></div><div style="margin-top:5pt;text-align:center"><font><br></font></div><div style="margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:32.233%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:32.233%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:32.234%"></td><td style="width:0.1%"></td></tr><tr><td colspan="9" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:115%">2023 Equity and Incentive Plan</font></div></td></tr><tr><td colspan="9" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(Full title of plan)</font></td></tr></table></div><div style="margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:27.993%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:41.151%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:27.556%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-top:6pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">Marcy D. Mutch</font></div></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">Executive Vice President and Chief Financial Officer</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">401 North 31st Street</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">Billings, Montana 59101</font></td><td colspan="3" style="border-bottom:1pt solid #000;padding:0 1pt"></td></tr><tr><td colspan="9" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(Name and address of agent for service)</font></td></tr></table></div><div style="margin-bottom:6pt;margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:27.993%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:41.151%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:27.556%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-bottom:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">(406) 255-5311</font></td><td colspan="3" style="border-bottom:1pt solid #000;padding:0 1pt"></td></tr><tr><td colspan="9" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(Telephone number, including area code, of agent for service)</font></td></tr></table></div><div style="margin-bottom:2pt;margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.853%"><tr><td style="width:1.0%"></td><td style="width:28.182%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:40.920%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:27.598%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">Copy to&#58;</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">Scott A. Berdan, Esq.<br>Polsinelli PC<br>1401 Lawrence Street, Suite 2300 <br>Denver, CO 80202 <br>(303) 572-9300</font></td><td colspan="3" style="padding:0 1pt"></td></tr></table></div><div style="margin-bottom:2pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">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="margin-bottom:2pt;margin-top:5pt;text-align:center;text-indent:13.5pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:96.929%"><tr><td style="width:0.1%"></td><td style="width:0.403%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:21.071%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:7.798%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:18.357%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:26.200%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:20.471%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Large accelerated filer&#160; </font><font style="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#253;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Accelerated filer &#160;</font><font style="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:100%">o</font></div></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Non-accelerated filer&#160; </font><font style="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:100%">o</font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Smaller reporting company&#160;</font><font style="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:100%">o</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </font></div></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Emerging growth company&#160;</font><font style="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:100%">o</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </font></div></td><td colspan="3" style="padding:0 1pt"></td></tr></table></div><div style="margin-bottom:2pt;margin-top:6pt;text-align:justify"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">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="color:#000000;font-family:'Wingdings',sans-serif;font-size:10pt;font-weight:400;line-height:120%">o</font></div><div style="height:42.75pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:42.75pt;width:100%"><div><font><br></font></div></div><div style="margin-top:5pt;padding-left:108pt;padding-right:108pt;text-align:center;text-indent:18pt"><font><br></font></div><div id="i70ac8497212b4c4dbe2951960fe714b8_4"></div><div style="text-align:center;text-indent:18pt"><font><br></font></div><div style="text-align:center;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:112%">EXPLANATORY NOTE</font></div><div><font><br></font></div><div style="margin-bottom:10pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">This Registration Statement is being filed in accordance with General Instruction E to Form S-8 for the purpose of registering 2,000,000 additional shares of common stock, $0.00001 par value, of First Interstate BancSystem, Inc., a Delaware corporation (the &#8220;Registrant&#8221;), reserved for issuance under the Registrant&#8217;s 2023 Equity and Incentive Plan, as amended. These shares are additional securities of the same class as other securities for which a registration statement of the Registrant on Form S-8 relating to the same employee benefit plan is effective.</font></div><div style="margin-bottom:12pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In accordance with General Instruction E to Form S-8, the Registrant&#8217;s Form S-8 Registration Statement filed with the Securities and Exchange Commission (the &#8220;Commission&#8221;) on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/860413/000086041323000125/fibk-20230525xsx8.htm" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 25, 2023</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 333-272210), is hereby incorporated by reference.</font></div><div id="i70ac8497212b4c4dbe2951960fe714b8_7"></div><div style="-sec-extract:summary;text-align:center;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">PART II</font></div><div style="text-align:center;text-indent:18pt"><font><br></font></div><div style="margin-bottom:10pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Item 3. Incorporation of Documents by Reference</font></div><div style="margin-bottom:10pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following documents filed by the Registrant with the Commission are incorporated by reference into this Registration Statement&#58;</font></div><div style="margin-bottom:10pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(a)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:6.91pt">the Registrant&#8217;s Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Commission on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000016/fibk-20231231.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">February 29, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 001-34653)&#59; </font></div><div style="margin-bottom:10pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(b)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:6.34pt">the information specifically incorporated by reference into the Registrant&#8217;s Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Commission on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000016/fibk-20231231.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">February 29, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 001-34653), from the Registrant&#8217;s definitive Proxy Statement, filed with the Commission under cover of Schedule 14A on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000053/fibk-20240411.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">April 11, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 001-34653)&#59; </font></div><div style="margin-bottom:10pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(c)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:6.91pt">the Registrant&#8217;s Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, filed with the Commission on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/860413/000086041324000066/fibk-20240331.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 3, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 001-34653)&#59; </font></div><div style="margin-bottom:10pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(d)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:6.34pt">the Registrant&#8217;s Current Reports on Form 8-K filed with the Commission on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000003/fibk-20240130.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">January 30, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (with respect only to Item 8.01 thereof) (File No. 001-34653), </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000047/fibk-20240402.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">April 2, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 001-34653), </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000059/fibk-20240424.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">April 24, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (with respect only to Item 8.01 thereof) (File No. 001-34653) and </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000071/fibk-20240520.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 23, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (with respect only to Items 5.02 and 5.07 thereof) (File No. 001-34653).</font></div><div style="margin-bottom:10pt;padding-left:36pt;text-indent:-18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(e)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:6.91pt">the description of the Registrant&#8217;s common stock, which is contained in a Registration Statement on Form 8-A (Amendment No. 3) filed with the Commission on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/860413/000086041323000117/form8-aa20230525.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">May 25, 2023</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, as updated by the description contained in </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/860413/000086041324000016/fibk-20231231xex41_descxse.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">Exhibit 4.1</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> of the Registrant&#8217;s Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Commission on </font><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041324000016/fibk-20231231.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">February 29, 2024</a></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (File No. 001-34653), and any further amendments or reports filed for the purpose of updating such description.</font></div><div style="margin-bottom:10pt;text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">All other reports and documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (specifically excluding Current Reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits furnished on any such form that relate to such items) on or after the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part of this Registration Statement from the date of the filing of such reports and documents. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document that also is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.</font></div><div style="height:42.75pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:42.75pt;width:100%"><div><font><br></font></div></div><div style="margin-bottom:8pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:112%">Item 8. Exhibits </font></div><div><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:10.791%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.373%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:86.436%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:justify"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:112%">Exhibit No.</font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:justify"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:112%">Exhibit Description</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/860413/000086041323000115/fibk-20230525xex31.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">4.1</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Certificate of Incorporation (incorporated by reference to Exhibit 3.1 to the Registrant&#8217;s Current Report on Form 8-K, filed with the Commission on May 25, 2023).</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="https://www.sec.gov/Archives/edgar/data/860413/000086041324000066/fibk-20240331xex_bylaws.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">4.2</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Bylaws (incorporated by reference to Exhibit 3.2 to the Registrant&#8217;s Form 10-Q, filed with the Commission on May 3, 2024).</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="fibk-20240523xex51polsinel.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">5.1</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Opinion of Polsinelli PC.</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="fibk-20240523xex231_consen.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">23.1</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Consent of RSM US LLP, independent registered public accounting firm.</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="fibk-20240523xex51polsinel.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">23.2</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Consent of Polsinelli PC (included in Exhibit 5.1).</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="#i70ac8497212b4c4dbe2951960fe714b8_13" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">24.1</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Power of Attorney (included on the signature page of this Form S-8).</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="https://www.sec.gov/ix?doc=/Archives/edgar/data/0000860413/000086041323000072/fibk-20230411.htm#if99a54f473c64137af3a58990971aedf_94" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">99.1</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">2023 Equity and Incentive Plan (incorporated by reference to Appendix C to the Registrant&#8217;s definitive Proxy Statement, filed with the Commission under cover of Schedule 14A on April 11, 2023)</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="fibk-20240523xex992_amendm.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">99.2</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">First Amendment to 2023 Equity and Incentive Plan.</font></div></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div style="text-align:center"><font style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline"><a href="fibk-20240523xex107_feetab.htm" style="-sec-extract:exhibit;color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%;text-decoration:underline">107</a></font></div></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Fee Table.</font></div></td></tr></table></div><div><font><br></font></div><div style="margin-bottom:8pt"><font><br></font></div><div style="height:42.75pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><div id="i70ac8497212b4c4dbe2951960fe714b8_10"></div><hr style="page-break-after:always"><div style="min-height:42.75pt;width:100%"><div><font><br></font></div></div><div style="margin-bottom:14pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">SIGNATURES</font></div><div style="text-indent:18pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">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-8 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 the 23rd day of May, 2024. </font></div><div style="margin-bottom:10pt;margin-top:5pt;text-align:center;text-indent:18pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.415%"><tr><td style="width:1.0%"></td><td style="width:46.694%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:4.047%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:45.959%"></td><td style="width:0.1%"></td></tr><tr style="height:15pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="6" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:700;line-height:100%">FIRST INTERSTATE BANCSYSTEM, INC.</font></td></tr><tr style="height:15pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:100%">By&#58;</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:100%">&#47;s&#47; KIRK D. JENSEN</font></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:100%">Kirk D. Jensen</font></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:100%">Executive Vice President and General Counsel&#47;Corporate Secretary</font></td></tr></table></div><div style="height:42.75pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div><div id="i70ac8497212b4c4dbe2951960fe714b8_13"></div><hr style="page-break-after:always"><div style="min-height:42.75pt;width:100%"><div><font><br></font></div></div><div style="margin-bottom:14pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:112%">POWER OF ATTORNEY</font></div><div style="margin-bottom:10pt;text-indent:39.6pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Kevin P. Riley, Kirk D. Jensen, and Marcy D. Mutch, and each of them, as his or her true and lawful attorneys-in-fact and agents, each with the full power of substitution, for him or her and in their name, place or stead, in any and all capacities, to sign any and all amendments to this Registration Statement (including post-effective amendments), and to sign any registration statement for the same offering covered by this Registration Statement that is to be effective upon filing pursuant to Rule 462(b) promulgated under the Securities Act, and all post-effective amendments thereto, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or his, her or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.</font></div><div style="margin-bottom:10pt;text-indent:28.8pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:112%">Pursuant to the requirements of the Securities Act, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.</font></div><div style="margin-bottom:3pt;margin-top:4pt;text-indent:15.75pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:438.75pt"><tr><td colspan="3" style="display:none"></td><td style="width:1.0pt"></td><td style="width:142.00pt"></td><td style="width:1.0pt"></td><td style="width:1.0pt"></td><td style="width:217.00pt"></td><td style="width:1.0pt"></td><td style="width:1.0pt"></td><td style="width:73.75pt"></td><td style="width:1.0pt"></td></tr><tr style="height:14pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Signature</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Title</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Date</font></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:14pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; DAVID L. JAHNKE</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:14pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">David L. Jahnke</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; STEPHEN B. BOWMAN</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Stephen B. Bowman</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; ALICE S. CHO</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Alice S. Cho</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; FRANCES P. GRIEB</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Frances P. Grieb</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; THOMAS E. HENNING</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Thomas E. Henning</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; JOHN M. HEYNEMAN, JR.</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">John M. Heyneman, Jr.</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; DENNIS L. JOHNSON</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Dennis L. Johnson</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; STEPHEN M. LACY</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Stephen M. Lacy</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; PATRICIA L. MOSS</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Patricia L. Moss</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; JOYCE A. PHILLIPS</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Joyce Phillips</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; DANIEL A. RYKHUS</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Daniel A. Rykhus</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; JAMES R. SCOTT</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">James R. Scott</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; JONATHAN R. SCOTT</font></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Jonathan R. Scott</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Director</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:9pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; KEVIN P. RILEY</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">President, Chief Executive Officer and Director</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:12pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Kevin P. Riley</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:100%">(Principal executive officer)</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:15pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">&#47;s&#47; MARCY D. MUTCH</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Executive Vice President and Chief Financial Officer</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">May 23, 2024</font></td></tr><tr style="height:15pt"><td colspan="3" style="display:none"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Marcy D. Mutch</font></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:100%">(Principal financial and accounting officer)</font></td><td colspan="3" style="padding:0 1pt"></td></tr><tr style="height:3pt"><td colspan="3" style="display:none"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td></tr></table></div><div style="height:42.75pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div><font><br></font></div></div></div></body></html>
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Document
As filed with the Securities and Exchange Commission on May 23, 2024
Registration No 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
First Interstate BancSystem, Inc.
(Exact name of registrant as specified in its charter)
Delaware
81-0331430
(State or other jurisdiction of incorporation or organization)
(I.R.S. Employer Identification Number)
401 North 31st Street, Billings, Montana
59101
(Address of principal executive offices)
(Zip Code)
2023 Equity and Incentive Plan
(Full title of plan)
Marcy D. Mutch
Executive Vice President and Chief Financial Officer
401 North 31st Street
Billings, Montana 59101
(Name and address of agent for service)
(406) 255-5311
(Telephone number, including area code, of agent for service)
Copy to:
Scott A. Berdan, Esq.
Polsinelli PC
1401 Lawrence Street, Suite 2300
Denver, CO 80202
(303) 572-9300
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 "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer
ý
Accelerated filer
o
Non-accelerated filer
o
Smaller reporting company
o
Emerging growth company
o
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.
o
EXPLANATORY NOTE
This Registration Statement is being filed in accordance with General Instruction E to Form S-8 for the purpose of registering 2,000,000 additional shares of common stock, $0.00001 par value, of First Interstate BancSystem, Inc., a Delaware corporation (the "Registrant"), reserved for issuance under the Registrant's 2023 Equity and Incentive Plan, as amended. These shares are additional securities of the same class as other securities for which a registration statement of the Registrant on Form S-8 relating to the same employee benefit plan is effective.
In accordance with General Instruction E to Form S-8, the Registrant's Form S-8 Registration Statement filed with the Securities and Exchange Commission (the "Commission") on
May 25, 2023
(File No. 333-272210), is hereby incorporated by reference.
PART II
Item 3. Incorporation of Documents by Reference
The following documents filed by the Registrant with the Commission are incorporated by reference into this Registration Statement:
(a)
the Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Commission on
February 29, 2024
(File No. 001-34653);
(b)
the information specifically incorporated by reference into the Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Commission on
February 29, 2024
(File No. 001-34653), from the Registrant's definitive Proxy Statement, filed with the Commission under cover of Schedule 14A on
April 11, 2024
(File No. 001-34653);
(c)
the Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, filed with the Commission on
May 3, 2024
(File No. 001-34653);
(d)
the Registrant's Current Reports on Form 8-K filed with the Commission on
January 30, 2024
(with respect only to Item 8.01 thereof) (File No. 001-34653),
April 2, 2024
(File No. 001-34653),
April 24, 2024
(with respect only to Item 8.01 thereof) (File No. 001-34653) and
May 23, 2024
(with respect only to Items 5.02 and 5.07 thereof) (File No. 001-34653).
(e)
the description of the Registrant's common stock, which is contained in a Registration Statement on Form 8-A (Amendment No. 3) filed with the Commission on
May 25, 2023
, as updated by the description contained in
Exhibit 4.1
of the Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Commission on
February 29, 2024
(File No. 001-34653), and any further amendments or reports filed for the purpose of updating such description.
All other reports and documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (specifically excluding Current Reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits furnished on any such form that relate to such items) on or after the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part of this Registration Statement from the date of the filing of such reports and documents. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document that also is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.
Item 8. Exhibits
Exhibit No.
Exhibit Description
4.1
Certificate of Incorporation (incorporated by reference to Exhibit 3.1 to the Registrant's Current Report on Form 8-K, filed with the Commission on May 25, 2023).
4.2
Bylaws (incorporated by reference to Exhibit 3.2 to the Registrant's Form 10-Q, filed with the Commission on May 3, 2024).
5.1
Opinion of Polsinelli PC.
23.1
Consent of RSM US LLP, independent registered public accounting firm.
23.2
Consent of Polsinelli PC (included in Exhibit 5.1).
24.1
Power of Attorney (included on the signature page of this Form S-8).
99.1
2023 Equity and Incentive Plan (incorporated by reference to Appendix C to the Registrant's definitive Proxy Statement, filed with the Commission under cover of Schedule 14A on April 11, 2023)
99.2
First Amendment to 2023 Equity and Incentive Plan.
107
Fee Table.
SIGNATURES
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-8 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 the 23rd day of May, 2024.
FIRST INTERSTATE BANCSYSTEM, INC.
By:
/s/ KIRK D. JENSEN
Kirk D. Jensen
Executive Vice President and General Counsel/Corporate Secretary
POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Kevin P. Riley, Kirk D. Jensen, and Marcy D. Mutch, and each of them, as his or her true and lawful attorneys-in-fact and agents, each with the full power of substitution, for him or her and in their name, place or stead, in any and all capacities, to sign any and all amendments to this Registration Statement (including post-effective amendments), and to sign any registration statement for the same offering covered by this Registration Statement that is to be effective upon filing pursuant to Rule 462(b) promulgated under the Securities Act, and all post-effective amendments thereto, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or his, her or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Act, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.
Signature
Title
Date
/s/ DAVID L. JAHNKE
May 23, 2024
David L. Jahnke
Director
/s/ STEPHEN B. BOWMAN
May 23, 2024
Stephen B. Bowman
Director
/s/ ALICE S. CHO
May 23, 2024
Alice S. Cho
Director
/s/ FRANCES P. GRIEB
May 23, 2024
Frances P. Grieb
Director
/s/ THOMAS E. HENNING
May 23, 2024
Thomas E. Henning
Director
/s/ JOHN M. HEYNEMAN, JR.
May 23, 2024
John M. Heyneman, Jr.
Director
/s/ DENNIS L. JOHNSON
May 23, 2024
Dennis L. Johnson
Director
/s/ STEPHEN M. LACY
May 23, 2024
Stephen M. Lacy
Director
/s/ PATRICIA L. MOSS
May 23, 2024
Patricia L. Moss
Director
/s/ JOYCE A. PHILLIPS
May 23, 2024
Joyce Phillips
Director
/s/ DANIEL A. RYKHUS
May 23, 2024
Daniel A. Rykhus
Director
/s/ JAMES R. SCOTT
May 23, 2024
James R. Scott
Director
/s/ JONATHAN R. SCOTT
May 23, 2024
Jonathan R. Scott
Director
/s/ KEVIN P. RILEY
President, Chief Executive Officer and Director
May 23, 2024
Kevin P. Riley
(Principal executive officer)
/s/ MARCY D. MUTCH
Executive Vice President and Chief Financial Officer
May 23, 2024
Marcy D. Mutch
(Principal financial and accounting officer)