The town of Newburgh is bordered on the north by the town of Plattekill (Ulster County) and the town of Marlborough (Ulster County), which includes the hamlet of Marlboro. It is bordered on the west by the town of Shawangunk (Ulster County) which includes the hamlet of Wallkill and by the town of Montgomery (Orange County), which includes the villages of Walden, Montgomery and Maybrook. The entire southern boundary is with the town of New Windsor (Orange County) with the exception of a quadrant, nearly a perfect quadrilateral in shape, adjoining the town at its southeast corner. This is the city of Newburgh. The eastern boundary of the town of Newburgh is the Hudson River, which separates it from the Dutchess County towns of Poughkeepsie, Wappinger, and Fishkill.