Form 4 Filing for Shepler Christopher L. of FIRST INTERSTATE BANCSYSTEM INC

On March 15, 2026, Christopher L. Shepler, Chief Banking Officer of FIRST INTERSTATE BANCSYSTEM INC (FIBK), acquired 5,971 shares of common stock under the company's 2023 Equity and Incentive Plan. These shares represent restricted stock units that vest in three equal annual installments starting March 15, 2027, contingent upon continued employment. The acquisition was made at a price of $33.13 per share, resulting in a post-transaction ownership of 9,870 shares. The filing, designated as Form 4, was signed by Kirk D. Jensen as Attorney-in-Fact on March 17, 2026. The shares are directly owned by Mr. Shepler.