SC 203 begins at an intersection with SC 20 (North Main Street) on the northeastern corner of the central square in Abbeville, Abbeville County, where the roadway continues as Trinity Street.

It travels to the northeast and immediately curves to the north-northeast before crossing over Parker Creek.

It passes Abbeville High School just before leaving the city limits.

SC 203 Truck travels to the northwest on South Main Street.

At the next intersection, it reaches its northern terminus, the SC 203 mainline (Washington Street).