There are 10 US Post Offices in Spink County serving a total of 6,595 residents equating to 660 residents per post office. It's estimated that approximately 10,526 packages are handled across the 10 county post offices annually. Spink County is a county located in the U.S. state of South Dakota. As of the 2010 census, the population was 6,415. Its county seat is Redfield. The county was created in 1873 and organized in 1879 within Dakota Territory."