What are the Iona, South Dakota Zip Codes for 2020, 2019Primary Zip Codes for IonaZip CodePrimary CitySecondary City57533GregoryIona, Carlock, Dixon,Cities sharing Zip Codes with IonaZip CodePrimary CitySecondary CityMore Information57533GregoryDixon57533GregoryIona57533GregoryCarlockAdvertisements