NY 205 begins at exit 13 off I-88 just north of the Susquehanna River in the town of Oneonta. Southeast of I-88, the roadway continues for as NY 991D, an unsigned reference route. The two-lane NY 205 heads northwestward from the exit, crossing the Interstate Highway and passing north of an office park built up alongside the freeway. Another overpass brings NY 205 over the Delaware and Hudson Railway and leads to an intersection with NY 7 (Oneida Street), the main east–west surface road through the city of Oneonta. Past NY 7, the route turns northward, serving the former National Soccer Hall of Fame and another office park prior to crossing County Route 8 (CR 8, named Country Club Road). NY 205 continues on, passing through a residential area adjacent to Oneonta County Club and intersecting with NY 23 (Chestnut Street) at the club's eastern edge. NY 23 turns north at the junction, overlapping with NY 205 for about to the outskirts of the town.