Greenwich Township is a township in Gloucester County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 4,917, an increase of 18 (+0.4%) from the 2010 census count of 4,899, which in turn reflected an increase of 20 (+0.4%) from the 4,879 counted in the 2000 census.

Gloucester County is a county in the U.S. state of New Jersey. As of the 2020 census, the county was the state's 14th-most populous county with a population of 302,294, its highest decennial count ever and an increase of 14,006 (+4.9%) from the 288,288 counted in the 2010 census, which in turn represented an increase of 33,615 (+13.2%) from the 2000 census population of 254,673. Its county seat is Woodbury. The county is part of the South Jersey region of the state.