North Chicago, IL is currently utilizing two area codes 224 and 847 which is an area code overlay serving the same geographic area. The area code overlay was established in 2002 at which time area code 224 was created as an overlay of area code 847. Area code 847 was originally established in 1996. Ten digit dialing (area code + seven digit number) is necessary because two different homes in the same geographic area can have the same seven digit phone number but each would have a different area code.
In addition to North Chicago, IL area codes 224 and 847 serve northeastern Illinois including the larger cities and communities of Arlington Heights, Buffalo Grove, Carpentersville, Des Plaines, Elgin, Elk Grove Village, Evanston, Glenview, Gurnee, Highland Park, Hoffman Estates, Lake Forest, Lake in the Hills, Libertyville, Morton Grove, Mount Prospect, Mundelein, Niles, North Chicago, Northbrook, Palatine, Park Ridge, Rolling Meadows, Round Lake Beach, Schaumburg, Skokie, Vernon Hills, Waukegan, Wheeling, Wilmette and Zion, in addition to many smaller communities within the service area.
North Chicago, IL is located in Lake County and observes the Central Time Zone.