Where Is Area Code 779?
Area code 779 serves northern Illinois, with Joliet as its primary city. It covers parts of the Chicago metropolitan area around Joliet and a broad north-central region that shares the same geographic footprint as area code 815. The service area is in the Great Lakes region and observes Central Time.
Area code 779 reaches communities in parts of Will, Kendall, Grundy, Kankakee, LaSalle, DeKalb, Ogle, Winnebago, Stephenson, Lee, Whiteside, Boone, Bureau, and Livingston counties. Major communities include Rockford, DeKalb, Kankakee, Freeport, Dixon, Sterling, Ottawa, La Salle, Peru, Morris, Pontiac, and Rochelle. Notable geographic features include the Des Plaines River at Joliet, the Illinois River near Ottawa, and the Rock River near Rockford and Sterling.
Cities and Communities in the 779 Area Code
- Belvidere, Boone County
- DeKalb, DeKalb County
- Dixon, Lee County
- Freeport, Stephenson County
- Joliet, Will and Kendall counties
- Kankakee, Kankakee County
- La Salle, LaSalle County
- Mendota, LaSalle County
- Morris, Grundy County
- Ottawa, LaSalle County
- Peru, LaSalle County
- Pontiac, Livingston County
- Princeton, Bureau County
- Rochelle, Ogle County
- Rockford, Winnebago County
- Sterling, Whiteside County
- Streator, LaSalle and Livingston counties
- Sycamore, DeKalb County
History of Area Code 779
Area code 779 entered service in 2009 as an overlay of area code 815. Area code 815 was part of the original North American Numbering Plan established in 1947. The overlay added new telephone numbers to the same region instead of creating a separate geographic district.
Area code 779 did not result from a geographic split, and area code 815 remained in use. Because both codes share one geographic footprint, local calls in the region use 10-digit dialing. The overlay addressed growing demand for residential, business, and wireless telephone numbers across northern Illinois.
Key Facts About Area Code 779
- Area code 779 is a geographic telephone area code in Illinois, and Joliet is its primary city.
- Area code 779 serves northern Illinois in the Great Lakes U.S. Census region.
- Area code 779 uses Central Time.
- Area code 779 is an overlay of area code 815, not an original area code or a geographic split.
- Area code 779 entered service in 2009.
- Area code 815 was established in 1947 as part of the original North American Numbering Plan.
- Northern Illinois University is in DeKalb, the University of St. Francis and Chicagoland Speedway are in Joliet, and Starved Rock State Park is near Ottawa.
- Local calls within the shared 779 and 815 region use 10-digit dialing.
Frequently Asked Questions
What state is area code 779 in?
Area code 779 is in Illinois.
What major cities use area code 779?
Major cities associated with area code 779 include Joliet, Rockford, DeKalb, Kankakee, Freeport, Dixon, Ottawa, Sterling, La Salle, Peru, and Morris.
What time zone is area code 779 in?
Area code 779 is in Central Time.
Is area code 779 a toll-free number?
No, area code 779 is a geographic area code, not a toll-free number.