Fair Lawn is a borough in Bergen County, in the U.S. state of New Jersey, and a bedroom suburb located 12 miles (19 km) northwest of New York City. As of the 2020 United States census, the borough's population was 34,927, an increase of 2,470 (+7.6%) from the 2010 census count of 32,457, which in turn reflected an increase of 820 (+2.6%) from the 31,637 counted in the 2000 census.