South Carolina Highway 99 (SC 99) is a 9.220-mile-long (14.838 km) state highway in the U.S. state of South Carolina.

The highway connects Great Falls with rural areas of Chester County.

On the edge of the city limits of the town is an intersection with SC 97 (Francis Avenue).

SC 99 travels in a north-northwesterly direction and passes Howze Cemetery.

The highway continues traveling through rural areas and meets its northern terminus, an intersection with SC 9 (Lancaster Highway).