PA 63 begins at a "T" intersection with PA 29 in the borough of Green Lane in Montgomery County. From this intersection, the route heads southeast as two-lane undivided Main Street, passing by several homes. After crossing Upper Ridge Road, the road enters Marlborough Township and becomes Sumneytown Pike. PA 63 continues through rural areas with some development, passing through the community of Sumneytown. Upon crossing Unami Creek, the route enters Upper Salford Township and heads into forested areas, where PA 63 meets the southern terminus of PA 563 (Ridge Road). Following that intersection, the road passes through a mix of farmland, woodland, and residential developments. The route crosses over the East Branch Perkiomen Creek before entering Lower Salford Township. At this point, PA 63 becomes Main Street and heads into the community of Harleysville, where it passes through suburban residential neighborhoods before heading into a commercial area, crossing PA 113 (Harleysville Pike).