Barnwell County Post Offices

221 Main St
Barnwell, South Carolina 29812

476 Main St
Blackville, South Carolina 29817

10049 Us Highway 78
Elko, South Carolina 29826

12926 Main St
Williston, South Carolina 29853

Barnwell County

There are 4 US Post Offices in Barnwell County serving a total of 23,521 residents equating to 5,880 residents per post office. It's estimated that approximately 37,542 packages are handled across the 4 county post offices annually. Barnwell County is a county located in the U.S. state of South Carolina. As of the 2010 census, its population was 22,621. Its county seat is Barnwell.