West Chicago is a city in DuPage County, Illinois, United States. The population was 25,614 at the 2020 census. It was formerly named Junction and later Turner Junction, after its founder, John Bice Turner, president of the Galena and Chicago Union Railroad in 1855. The city was initially established around the first junction of railroad lines in Illinois, and today is still served by the Union Pacific West Metra service via West Chicago station.