Its northern terminus is located at U.S. Route 20 (US 20) in Harborcreek Township.

The road passes through a mix of farmland and woodland before it reaches an interchange with Interstate 90 (I-90).

After this interchange, the route turns to the northwest at a truck stop and continues past woods to the northeast and residential subdivisions to the southwest.

PA 531 curves north again as it passes a couple farms before heading northwest near rural areas of homes.

The route reaches its northern terminus at an intersection with US 20 next to Harbor Creek Jr./Sr.