Credit Union in Grinnell, IA The Grinnell branch, established in 1998, was the first location opened north of Interstate-80. The branch offers a full-range of financial services and is dedicated to helping our members achieve financial success. This location includes an Interactive Teller Machine (C1st InTouch) - It looks like an ATM, the difference is you can have a real-time, face-to-face conversation with a C1st Teller, make cash withdrawals, deposit cash or checks, cash checks, make certain loan payments, transfer funds and more! Check out our personal banking pages for any questions related to checking, savings, loans and online banking.