First Interstate Bank

Established in 1968, First Interstate Bank grew from a local Montana lender into the largest financial institution in the state. The bank operates as the primary brand for First Interstate BancSystem, Inc., managing a vast network of community banks across fourteen Western and Midwestern states including Wyoming, Idaho, Colorado, and Oregon.

The company emphasizes personal service over purely automated banking experiences. Employees at branches in Great Falls, Sheridan, and Bend regularly close early to volunteer for local nonprofits during the annual Volunteer Day. This commitment to community support distinguishes the brand from larger national competitors like Bank of America or Wells Fargo.

Financial stability remains a priority despite industry-wide challenges. In July 2026, federal regulators banned two former bankers associated with the institution for embezzling customer funds. The incident highlighted internal control issues but did not halt operations or expansion efforts. The holding company continues to trade on the NASDAQ under the ticker symbol FIBK. [edit]