Warren Township is a township in Somerset County, in the U.S. state of New Jersey. The township is a bedroom suburb of New York City in the much larger New York metropolitan area, located within the Raritan Valley region. As of the 2020 United States census, the township's population was 15,923, an increase of 612 (+4.0%) from the 2010 census count of 15,311, which in turn reflected an increase of 1,052 (+7.4%) from the 14,259 counted in the 2000 census. Warren is situated in northeastern Somerset County bordering both Morris and Union counties.