Cary is a village located in Algonquin Township, McHenry County, Illinois, United States. The population was 18,271 at the 2010 census.
In 1841, William Dennison Cary purchased 82 acres (33 ha) for $1.25 an acre at the location of the current town and built a farm. In 1856, Cary included a train station for the Illinois & Wisconsin Railway. The site was approved and a post office was added with the designation "Cary Station." The community around Cary Station was incorporated in 1893 as Cary, Illinois.