Dumont is a borough in Bergen County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 17,863, an increase of 384 (+2.2%) from the 2010 census count of 17,479, which in turn reflected a decrease of 24 (−0.1%) from the 17,503 counted in the 2000 census.