Pennsylvania Route 418 (PA 418) is an 3-mile (4.8 km) long state highway located in Mercer county in Pennsylvania. The southern terminus is at PA 760/PA 718 in Wheatland. The northern terminus is at US 62 in Hermitage.

PA 418 begins at an intersection with PA 718 and PA 760 in Wheatland, heading north on two-lane undivided Council Street. The route passes through residential areas, turning northeast onto Mercer Avenue and heading into Farrell. The road passes more homes and reaches an intersection with PA 518. A short distance after this junction, PA 418 enters Hermitage and heads into more wooded areas with a few residences. The route turns north onto Maple Drive and reaches its northern terminus at US 62.

The entire route is in Mercer County.