Pleasantville is a city in Atlantic County, in the U.S. state of New Jersey. As of the 2020 United States census, the city's population was 20,629, its highest decennial count ever and an increase of 380 (+1.9%) from the 2010 census count of 20,249, which in turn reflected an increase of 1,237 (+6.5%) from the 19,012 counted in the 2000 census.