St. Stephen is a town in Berkeley County, South Carolina, United States.

The Keller Site and St. Stephen's Episcopal Church are listed on the National Register of Historic Places.

[7] St. Stephen is located in northern Berkeley County at 33°24′18″N 79°55′24″W / 33.40500°N 79.92333°W / 33.40500; -79.92333 (33.405024, -79.923365),[8] between Lake Moultrie to the west and the Santee River to the northeast.

The town lies along the western edge of Francis Marion National Forest near its northernmost point.

According to the United States Census Bureau, the town has a total area of 2.4 square miles (6.2 km2), all of it land.