United States Government--for Zip Code Information Sergeant Bluff, IA 51054 Phone : (712) 943-5560 Business Category Government Offices-Federal Social Service & Welfare Organizations Information & Referral Services Government Offices & Public Schools Post Office - Sergeant Bluff 410 4th St Sergeant Bluff, IA 51054 Phone : (712) 943-5560 Business Category Post Offices Toll-Free           (800) ASK-USPS Sergeant Bluff Ia--united States Government, U S Post Office Sergeant Bluff, IA 51054 Phone : (712) 943-5560 Business Category Government Offices-Federal Post Offices Government Offices & Public Schools