Washington 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 48,677, an increase of 118 from the 2010 census count of 48,559, which in turn reflected an increase of 1,445 from the 47,114 counted in the 2000 census. For 2023, the Census Bureau's Populati…Washington 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 48,677, an increase of 118 from the 2010 census count of 48,559, which in turn reflected an increase of 1,445 from the 47,114 counted in the 2000 census. For 2023, the Census Bureau's Population Estimates Program calculated a population of 49,378.