Carteret is a borough in Middlesex County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 22,844, reflecting an increase of 2,135 (+10.3%) from the 20,709 counted in the 2000 Census, which had in turn increased by 1,684 (+8.9%) from the 19,025 counted in the 1990 Census.