United States Government--post Office, For Zip Code Information Holstein, IA 51025 Phone : (712) 368-2117 Business Category Government Offices-Federal Post Offices Government Offices & Public Schools Post Office - Holstein 121 E 2nd St Holstein, IA 51025 Phone : (712) 368-2117 Post Office - Holstein Business Category Post Offices Toll-Free           (800) ASK-USPS United States Government--social Security Admin, Post Office 121 E 2nd Holstein, IA 51025 Phone : (712) 368-2117 Business Category Government Offices-Federal Post Offices Government Offices & Public Schools United States Government--social Security Admin, For Zip Code Information Holstein, IA 51025 Phone : (712) 368-2117 Business Category Government Offices-Federal Government Offices & Public Schools