Pittstown is a town in Rensselaer County, New York, United States. The population was 5,735 at the 2010 census. It is in the northern part of the county. A small part of the northern town line is Rensselaer County's border with Washington County. Moving west, the Hoosic River defines the town's northwestern line to the crux of its border with the town of Schaghticoke, which juts south to form the western town line. The towns of Brunswick and Grafton border to the southwest and southeast, respectively, with the town of Hoosick to the east.