<SEC-DOCUMENT>0000860413-25-000045-index.html : 20250408 <SEC-HEADER>0000860413-25-000045.hdr.sgml : 20250408 <ACCEPTANCE-DATETIME>20250408160339 ACCESSION NUMBER: 0000860413-25-000045 CONFORMED SUBMISSION TYPE: DEF 14A PUBLIC DOCUMENT COUNT: 63 CONFORMED PERIOD OF REPORT: 20250408 FILED AS OF DATE: 20250408 DATE AS OF CHANGE: 20250408 FILER: COMPANY DATA: COMPANY CONFORMED NAME: FIRST INTERSTATE BANCSYSTEM INC CENTRAL INDEX KEY: 0000860413 STANDARD INDUSTRIAL CLASSIFICATION: STATE COMMERCIAL BANKS [6022] ORGANIZATION NAME: 02 Finance EIN: 810331430 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: DEF 14A SEC ACT: 1934 Act SEC FILE NUMBER: 001-34653 FILM NUMBER: 25821916 BUSINESS ADDRESS: STREET 1: 401 NO 31ST STREET CITY: BILLINGS STATE: MT ZIP: 59101 BUSINESS PHONE: 4062555311 MAIL ADDRESS: STREET 1: 401 NO 31ST STREET CITY: BILLINGS STATE: MT ZIP: 59101 FORMER COMPANY: FORMER CONFORMED NAME: FIRST INTERSTATE BANCSYSTEM OF MONTANA INC DATE OF NAME CHANGE: 19930615 </SEC-HEADER> <DOCUMENT> <TYPE>DEF 14A <SEQUENCE>1 <FILENAME>fibk-20250408.htm <DESCRIPTION>DEF 14A <TEXT> Document 1 - file: fibk-20250408.htm
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