In Preston, the open fields return as NY 220 follows another waterbody, this time the slightly larger Mill Brook. The route crosses the stream just before entering the town of Oxford, where they split. While Mill Brook curves around the western extents of the village of Oxford, NY 220 serves the village directly, entering it on Butler Street. It veers eastward at a junction with State Street and follows it to Washington Avenue. Here, State Street splits into a one-block long one-way couplet. Eastbound NY 220 shifts south to follow LaFayette Park; NY 220 westbound, meanwhile, is routed on State Street. At the end of the couplet, NY 220 intersects NY 12 (North Canal Street) on the western bank of the Chenango River.