Irvington is a township in Essex County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 61,176, an increase of 7,250 (+13.4%) from the 2010 census count of 53,926, which in turn reflected a decline of 6,769 (−11.2%) from the 60,695 counted in the 2000 census.