Chapin is a town in Lexington County, South Carolina, United States. The population was 1,445 at the 2010 census. It is part of the Columbia, South Carolina Metropolitan Statistical Area.
Chapin is located at 34°9′57″N 81°20′50″W / 34.16583°N 81.34722°W / 34.16583; -81.34722 (34.165783, -81.347260).
According to the United States Census Bureau, the town has a total area of 1.8 square miles (4.7 km²), of which, 1.8 square miles (4.7 km²) of it is land and 0.55% is water.