There are 9 US Post Offices in Guthrie County serving a total of 10,426 residents equating to 1,158 residents per post office. It's estimated that approximately 16,641 packages are handled across the 9 county post offices annually. Guthrie County is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 10,954. The county seat is Guthrie Center. The county was formed on January 15, 1851 and named after Captain Edwin B. Guthrie, who had died in the Mexican\u2013American War. Guthrie County is one of the five counties that make up the Des Moines\u2013West Des Moines, IA Metropolitan Statistical Area."