First Interstate BancSystem, Inc. On June 28, 2023, the registrant was notified by Scott E. Erkonen, the registrant’s Executive Vice President and Chief Information Officer, that he was departing from the Company for personal reasons effective immediately, and under circumstances enabling him to receive severance under his employment agreement with the registrant as if it were a resignation for “Good Reason” (as defined in his employment agreement). Mr. Erkonen’s departure was not related to a disagreement with the Company on any matter relating to the Company’s operations, policies or practices. The registrant’s Director of Enterprise Planning, Ms. Lori Meyer, has agreed to serve as the Company's Interim Chief Information Officer until a replacement is identified.

Ms. Meyer has been serving as Director of Enterprise Planning since 2018.