Union Map
Union is a village in McHenry County, Illinois, United States. The population was 580 at the 2010 census, up from 576 at the 2000 census.
Union is located at 42°14?7?N 88°32?33?W / 42.23528°N 88.5425°W / 42.23528; -88.5425 (42.235237, -88.542379).
According to the United States Census Bureau, the village has a total area of 0.6 square miles (1.6 km²), all of it land.
Nearby cities include Crystal Lake, Genoa, Burlington, Gilberts, Pingree Grove.