Where Is Area Code 815?
Area code 815 serves northern and north-central Illinois, including Joliet and communities west, southwest, and northwest of Chicago. Illinois is part of the Great Lakes census region, and area code 815 uses Central Time.
Major cities include Joliet in Will County, Rockford in Winnebago County, DeKalb in DeKalb County, Kankakee in Kankakee County, and Ottawa and La Salle in LaSalle County. The area also includes communities in Boone, Bureau, Grundy, Lee, Livingston, McHenry, Ogle, Stephenson, and Whiteside counties.
Notable geographic features include the Rock River near Rockford, Dixon, and Sterling, the Illinois River near Ottawa, Starved Rock State Park in LaSalle County, and the Des Plaines River around Joliet. The region includes river towns, farmland, and outer Chicago-area communities.
Cities and Communities in the 815 Area Code
- Amboy, Lee County
- Belvidere, Boone County
- Byron, Ogle County
- Coal City, Grundy County
- DeKalb, DeKalb County
- Dixon, Lee County
- Freeport, Stephenson County
- Galena, Jo Daviess County
- Harvard, McHenry County
- Joliet, Will County
- Kankakee, Kankakee County
- La Salle, LaSalle County
- Marengo, McHenry County
- Mendota, LaSalle County
- Morris, Grundy County
- Mount Morris, Ogle County
- Oregon, Ogle County
- Ottawa, LaSalle County
- Peru, LaSalle County
- Pontiac, Livingston County
- Princeton, Bureau County
- Rochelle, Ogle County
- Rock Falls, Whiteside County
- Rockford, Winnebago County
- Spring Valley, Bureau County
- Streator, LaSalle and Livingston counties
- Sterling, Whiteside County
- Sycamore, DeKalb County
- Wilmington, Will County
- Woodstock, McHenry County
History of Area Code 815
Area code 815 was established in 1947 as one of the original North American Numbering Plan area codes. It was assigned to northern Illinois, while area code 312 served Chicago, area code 217 served central Illinois, and area code 618 served southern Illinois.
Area code 815 later lost part of its original territory when area code 309 was created from it in 1957. Area code 779 entered service as an overlay for 815 on March 17, 2009. The overlay added telephone number capacity without requiring existing 815 customers to change their numbers.
Key Facts About Area Code 815
- Area code 815 is a geographic telephone area code in Illinois.
- Joliet, in Will County, is the primary city associated with area code 815.
- Area code 815 serves parts of northern and north-central Illinois in the Great Lakes census region.
- Area code 815 uses Central Time.
- Area code 815 was assigned in 1947 as an original North American Numbering Plan code.
- Area code 815 was split in 1957 when area code 309 was created for part of Illinois.
- Area code 779 has overlaid area code 815 since March 17, 2009.
- Northern Illinois University is located in DeKalb, and Starved Rock State Park is in LaSalle County, both within the 815 service region.
Frequently Asked Questions
What state is area code 815 in?
Area code 815 is in Illinois.
What major cities use area code 815?
Major cities using area code 815 include Joliet, Rockford, DeKalb, Kankakee, Ottawa, La Salle, Dixon, Sterling, Freeport, Morris, and Pontiac.
What time zone is area code 815 in?
Area code 815 is in Central Time.
Is area code 815 a toll-free number?
No. Area code 815 is a geographic area code, not a toll-free number.