Elizabeth is a city in Union County, 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 largest city (by population). The population increased by 4,401 (+3.7%) from the 120,568 counted in the 2000 Census, which had in turn increased by 10,566 (+9.6%) from the 110,002 counted in the 1990 Census. It is the county seat of Union County.
In 2008, Elizabeth was named one of "America's 50 Greenest Cities" by Popular Science magazine, the only city in New Jersey selected.