First Interstate Bank in Sully, IA offers a comprehensive suite of personal and business products to take care of your diverse financial needs. Whether you’re a first-time home buyer looking for a mortgage, an established business looking to streamline your payment methods, or someone who is ready to plan your financial future, our local banking experts at the First Interstate Bank Sully branch will help you reach your goals. First Interstate Bank is a community banking organization headquartered in Billings, Montana. With over 300 locations across 14 states, First Interstate is still run on the same principles as when it was founded by Homer Scott, Sr. in Sheridan, Wyoming in 1968 – to take the best possible care of our customers, our e...