There are 3 US Post Offices in Davison County serving a total of 20,273 residents equating to 6,758 residents per post office. It's estimated that approximately 32,358 packages are handled across the 3 county post offices annually. Davison County is a county located in the U.S. state of South Dakota. As of the 2010 census, the population was 19,504. Its county seat is Mitchell. The county was created in 1873 and organized in 1874. It was named for Henry C. Davison, the first settler in the county. Davison County is part of the Mitchell, SD Micropolitan Statistical Area."