Essex County is a county located in the northeastern part of the U.S. state of New Jersey. As of 2015, Essex County's Census-estimated population was 797,434, an increase of 1.7% from the 2010 United States Census, when its population was enumerated at 783,969, in turn a decrease of 1.2% (9,664 fewer residents) from the 793,633 enumerated in the 2000 Census and making it the third-most populous county in the state, having dropped behind Middlesex County, and one of only two counties in the state to see a decline in population during the decade between 2000 and 2010 (Cape May County being the other). Its county seat is Newark. It is part of the New York Metropolitan Area. The Bureau of Economic Analysis ranked the county as having the 94th-highest per capita income of all 3,113 counties in