There are 5 US Post Offices in Abbeville County serving a total of 20,497 residents equating to 4,099 residents per post office. It's estimated that approximately 32,715 packages are handled across the 5 county post offices annually. Abbeville County is a county located in the U.S. state of South Carolina. As of the 2010 census, its population was 25,417. Its county seat is Abbeville. It is the first county in the United States alphabetically. Abbeville County is included in the Greenwood, SC Micropolitan Statistical Area, which is also included in the Greenville-Spartanburg-Anderson, SC Combined Statistical Area."