Banks in Onawa, Iowa, the US. Banks locations in Onawa, Iowa. Find the nearest banks locations, near you. All types of business services ATM Bank Courthouse Finance Funeral home Insurance Lawyer School All banks in Onawa Open now Until 05:00 pm Great Southern Bank ATM Finance Bank +1 712-423-1105 921 Iowa Avenue, Onawa, Iowa 51040 Write a review Phone Hours Website Directions