Plattekill is a hamlet in Ulster County, New York, United States. The population was 1,296 at the 2020 census. The community, as is the town, is named after a local stream, the Platte Kill. Plattekill is in the southern part of the Town of Plattekill. The community is adjacent to the New York State Thruway at the junction of Routes 32 and 13 and is one mile north of the county line of Orange County.