SC 302 begins at an intersection with SC 125 south of Spiderweb, within Aiken County, where the roadway continues as Silver Bluff Road. It travels to the northeast and crosses over Long Branch and Town Creek. It then intersects U.S. Route 278. The highway curves to the north-northeast. It passes east of Boyd Pond Park. The highway enters Aiken and turns right onto SC 19 Truck/SC 302. The three highways travel concurrently to the east-northeast. Just south of Virginia Acres Park, they intersect SC 19. At this intersection, SC 19 Truck meets its southern terminus. SC 118/SC 302 travel to the northeast and go between Kennedy Middle School and Millbrook Elementary School. They pass Citizens Park and leave the city limits of Aiken before they curve to the north-northeast. After crossing some railroad tracks, they intersect US 78. At this intersection, US 78 Truck, which begins here, joins the concurrency. One block later, they intersect SC 4. SC 302 turns right, and both highways travel to the east-northeast. They curve to the northeast. They cross overShaw Creek just before curving to the east-southeast. Then, they curve back to the northeast. They cross the South Fork Edisto River and Cedar Creek. The two highways curve to the southeast and split north of Aiken State Park. SC 302 heads to the northeast and crosses over Burcalo Creek. Then, it crosses over Dean Swamp Creek and curves to the east-northeast and enters Wagener. Just northeast of Wagener–Salley High School, it intersects SC 113. They travel concurrently to the northeast through town. The concurrency intersects SC 39. Just over later, SC 113 and SC 302 split, with SC 302 heading to the east-northeast. The highway passes just south of Edisto Lake and travels through Berlin. Then, it crosses over the Edisto River on the Harsey's Bridge. This bridge marks the Lexington County line. SC 302 curves to the north-northeast. It passes west of Rast Pond just before entering Pelion. It passes Pelion Elementary School and Pelion Middle School before intersecting US 178. Just after leaving the city limits, it passes Fort Pond Elementary School. Then, the highway travels through Macedon. It has a concurrency with SC 6. They split in Edmund. SC 302 curves to the northeast and enters South Congaree, where it crosses Congaree Creek. After it leaves the city limits, it travels along the eastern edge of Columbia Metropolitan Airport and crosses Savana Branch. It travels along the western edge of Cayce and passes Airport High School. At Boston Avenue, east of the high school, it begins traveling along the Springdale–Cayce line. While along the line, it crosses over Sixmile Creek and has an interchange with Interstate 26. At Manley Street, it begins traveling along the West Columbia–Cayce line. Glenn Street marks the point where the highway enters West Columbia proper. Just over later, it meets its eastern terminus, an intersection with US 21/US 176/US 321.
