List of Illinois area codes


The U.S. state of Illinois is divided into ten distinct geographic numbering plan areas in the North American Numbering Plan, which are assigned a total of seventeen area codes. When the 86 original North American area codes where established in 1947, all of the Chicago metropolitan area was located in numbering plan area 312, the rest of northern Illinois was 815, central Illinois was 217, and southern Illinois was 618.
In 1954, the 217 and 618 numbering plan areas were slightly remapped, and in 1957, area code 815 was split for the assignment of area code 309 to western central Illinois. No further changes were made for 33 years. Since 2023, all numbering plan areas of the state are overlay complexes, requiring ten-digit dialing statewide.
Area codeYear
created		Parent
NPA		OverlayNumbering plan area
3121947–312/872Central city area of Chicago, including the Chicago Loop and the Near North Side
7731996312773/872Chicago area, exclusive of NPA 312
8722009312312/872City of Chicago
8722009773773/872City of Chicago
7081989312708/464South suburbs and inner west suburbs of Chicago, including the Chicago Southland and most west and south suburbs in Cook County including Melrose Park, Norridge, Oak Park, Oak Lawn, Chicago Heights, and Orland Park.
4642022708708/464South suburbs and inner west suburbs of Chicago, including the Chicago Southland and most west and south suburbs in Cook County including Melrose Park, Norridge, Oak Park, Oak Lawn, Chicago Heights, and Orland Park.
6301996708331/630West suburbs of Chicago in DuPage County and Kane County including Wheaton, Naperville, and Aurora
3312007630331/630West suburbs of Chicago in DuPage County and Kane County including Wheaton, Naperville, and Aurora
8471996708224/847North and northwest suburbs of Chicago including all of Lake County, part of McHenry County, northern Cook County, and northeastern Kane County. The NPA includes Evanston, Des Plaines, Waukegan, and most of Elgin.
2242002847224/847North and northwest suburbs of Chicago including all of Lake County, part of McHenry County, northern Cook County, and northeastern Kane County. The NPA includes Evanston, Des Plaines, Waukegan, and most of Elgin.
8151947–779/815Northern Illinois outside of the immediate Chicago area including Joliet, Kankakee, LaSalle, DeKalb, and Rockford
7792007815779/815Northern Illinois outside of the immediate Chicago area including Joliet, Kankakee, LaSalle, DeKalb, and Rockford
2171947–217/447Central Illinois, including the region running west from the Illinois-Indiana border through Danville, Effingham, Champaign–Urbana, Decatur, Springfield, Quincy until Illinois' western border with Missouri and Iowa
4472021217217/447Central Illinois, including the region running west from the Illinois-Indiana border through Danville, Effingham, Champaign–Urbana, Decatur, Springfield, Quincy until Illinois' western border with Missouri and Iowa
3091957217309/861Central-Western Illinois including Bloomington–Normal, Peoria, and all the way west to the Illinois part of the Quad Cities including Moline, and Rock Island
3091957815309/861Central-Western Illinois including Bloomington–Normal, Peoria, and all the way west to the Illinois part of the Quad Cities including Moline, and Rock Island
8612023309309/861Central-Western Illinois including Bloomington–Normal, Peoria, and all the way west to the Illinois part of the Quad Cities including Moline, and Rock Island
6181947–618/730Southern Illinois, including Carbondale and most of the Metro East region of St. Louis suburbs in Illinois
6181954217618/730Southern Illinois, including Carbondale and most of the Metro East region of St. Louis suburbs in Illinois
7302023618618/730Southern Illinois, including Carbondale and most of the Metro East region of St. Louis suburbs in Illinois