Known as Airport Road, the state highway runs 1.84 miles (2.96 km) from U.S. Route 11 (US 11) in Roanoke north to SR 117 in Hollins.

The state highway heads north as a two-lane undivided road between a shopping center to the west and a residential area to the east.

SR 118 continues through an industrial area to the east of Roanoke Regional Airport and intersects Municipal Road, which leads to Aviation Drive, the road that serves the airport terminal.

The state highway curves northeast and descends into a tunnel that passes under the airport's east–west runway.

At the north end of the tunnel, SR 118 enters Roanoke County, passes through a residential area, and reaches its northern terminus at SR 117 (Peters Creek Road) on the west side of Hollins.