Hartsville is a small city in Darlington County, South Carolina, United States. The population was 7,764 at the 2010 census.
Hartsville is located at 34°22′10″N 80°4′51″W / 34.36944°N 80.08083°W / 34.36944; -80.08083 (34.369474, -80.080783).
According to the United States Census Bureau, the city has a total area of 5.0 square miles (13.0 km²). 5.0 square miles (12.9 km²) of it is land and 0.04 square miles (0.1 km²) of it (0.60%) is water.