There are 10 US Post Offices in Mcdonald County serving a total of 22,639 residents equating to 2,264 residents per post office. It's estimated that approximately 36,134 packages are handled across the 10 county post offices annually. McDonald County is a county located in the southwestern corner of the U.S. state of Missouri. As of the 2010 census, the population was 23,083. Its county seat is Pineville. The county was organized in 1849 and named for Sergeant Alexander McDonald, a soldier in the American Revolutionary War. The county has three sites on the National Register of Historic Places, including the Old McDonald County Courthouse and the Powell Bridge. McDonald County is part of the Fayetteville\u2013Springdale\u2013Rogers, AR-MO Metropolitan Statistical Area.