First Interstate BancSystem, Inc. is a bank holding company for First Interstate Bank, providing banking products and services in the United States. It offers traditional deposit products such as checking, savings, and time deposits, along with repurchase agreements mainly for commercial and municipal depositors. The company also provides trust, employee benefit, investment management, insurance, agency, and custodial services, and its loan portfolio includes real estate, consumer, commercial, and agricultural loans. It serves individuals, businesses, municipalities, and other entities across a range of industries. Formerly known as First Interstate Bancsystem Of Montana, Inc., it changed its name to First Interstate BancSystem, Inc. in June 1993, was founded in 1879, and is headquartered in Billings, Montana.