Union Pacific Railroad--post Offices, Marthasville Marthasville, MO 63357 Phone : (636) 433-2272 Business Category Railroads Line-Haul Operating Post Offices Railroads Post Office - Marthasville 105 Depot St Marthasville, MO 63357 Phone : (636) 433-2272 Post Office - Marthasville Business Category Post Offices National Security Recruiting Us Armed Forces Toll-Free           (800) ASK-USPS United States Government--u.s. Postal Service, Marthasville Marthasville, MO 63357 Phone : (636) 433-2272 United States Government--u.s. Postal Service, Marthasville Business Category Government Offices-Federal National Security Recruiting Us Armed Forces Government Offices & Public Schools