Elizabeth is both the largest city and the county seat of Union County, in New Jersey, United States. As of the 2010 United States Census, the city had a total population of 124,969, retaining its ranking as New Jersey's fourth most populous city, behind Paterson. The population increased by 4,401 from the 120,568 counted in the 2000 Census, which had in turn increased by 10,566 from the 110,002 counted in the 1990 Census. For 2018, the Census Bureau's Population Estimates Program calculated a population of 128,885, an increase of 3.1% from the 2010 enumeration, ranking the city the 215th-most-populous in the nation.