Resident Population in Westchester County, NY was 990.81700 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Westchester County, NY reached a record high of 1001.43100 in January of 2020 and a record low of 865.69500 in January of 1982. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Westchester County, NY - last updated from the United States Federal Reserve on May of 2024.