NY 438 begins at an intersection with US 62 and NY 39 in northern Gowanda. The route heads north, inheriting the Buffalo Street moniker from US 62 and NY 39, which turn east at NY 438's southern terminus. Outside of the village in Collins, the route becomes Four Mile Level Road as it curves westward into the Cattaraugus Indian Reservation. As its name implies, the route traverses relatively level terrain for a stretch of roughly as it parallels the northern bank of Cattaraugus Creek to the northwest and west. During this stretch, NY 438 intersects both Versailles–Plank Road and Brant Road (southern terminus of County Route 9 or CR 9) and crosses over the narrow Clear Creek.