Post Office - Fenton 9979 Fenton Rd Fenton, IL 61251 Phone : (815) 778-4869 Business Category Post Offices Toll-Free           (800) ASK-USPS United States Government--lock & Dam No 17, Fenton 9979 Fenton Rd Lyndon, IL 61261 Phone : (815) 778-4869 Business Category Government Offices-Federal Government Offices & Public Schools