what county is westmont il
Westmont, Illinois. Westmont is a village in DuPage County, Illinois, United States. Westmont is a community of 5.03 square miles in area. Westmont had a 2000 population of 24,554, a partial special census was conducted 2007 resulting in a population of 26,211, and the census of 2010 put the population at 24,685.