Union City is a village located mostly within Branch County in the U.S. state of Michigan. As of the 2000 census, the village had a total population of 1,804.
The village is located mostly within Union Township, where the Coldwater River flows into the St. Joseph River. Michigan State Highway 60 passes just north of the village. A small portion of the village lies within Burlington Township in Calhoun County.
Union City is at 42°04'00"N, 85°08'10"W. The ZIP code is 49094 and the FIPS place code is 81360.
According to the United States Census Bureau, the village has a total area of 3.8 km2 (1.5 mi2). 3.8 km2 (1.5 mi2) of it is land and 0.68% is water.