North Brunswick is a township in Middlesex County, in the U.S. state of New Jersey. It is centrally located in the Raritan Valley region within the New York metropolitan area. As of the 2020 United States census, the township's population was 43,905, an increase of 3,163 (+7.8%) from the 2010 census count of 40,742, which in turn reflected an increase of 3,455 (+12.3%) from the 36,287 counted in the 2000 census.