PA 989 splits from Duss Avenue by turning east onto 24th Street, running past more residences as it forms the border between Ambridge to the south and Harmony Township to the north.

The route fully enters Harmony Township, becoming Breitenstein Road as it winds east through wooded areas with some residences.

[2][3] PA 989 passes near a couple housing developments before leaving Economy for New Sewickley Township and becoming an unnamed road.

After passing through several miles of rural areas, PA 989 comes to a bridge over the Pennsylvania Turnpike (I-76) before the route turns northwest onto Glen Eden Road.

Here, the road heads through areas of farms and homes, running a short distance to the north of the Pennsylvania Turnpike.