Illinois Area Codes
Directory of all 17 telephone area codes assigned to Illinois.
Illinois phone numbers are served by 17 area codes operating in the Central timezone.Because an overlay is active, 10-digit dialing is mandatory across much of the state. No area codes in Illinois are currently flagged as high-risk scams.
Most populated prefix: area code 312 (Illinois)
All Area Codes in Illinois
Area Code 217
Springfield, Champaign, Decatur, Urbana, Quincy, Danville, Jacksonville, Charleston, Mattoon, Chatham
Area Code 224
Elgin, Waukegan, Schaumburg, Evanston, Arlington Heights, Skokie, Palatine, Des Plaines, Mount Prospect, Hoffman Estates
Area Code 309
Peoria, Bloomington, Normal, Moline, Romeoville, Rock Island, Pekin, Galesburg, East Peoria, Crest Hill
Area Code 312
Chicago, West Chicago
Area Code 331
Aurora, Naperville, Schaumburg, Bolingbrook, Wheaton, Downers Grove, Elmhurst, Lombard, Bartlett, Oswego
Area Code 447
Springfield, Champaign, Decatur, Urbana, Quincy, Danville, Jacksonville, Charleston, Mattoon, Chatham
Area Code 464
Cicero, Orland Park, Oak Lawn, Tinley Park, Berwyn, Oak Park, Calumet City, Burbank, Lansing, Oak Forest
Area Code 618
Belleville, O'fallon, Granite City, Edwardsville, Alton, Collinsville, Carbondale, East St. Louis, Godfrey, Marion
Area Code 630
Aurora, Naperville, Schaumburg, Bolingbrook, Wheaton, Downers Grove, Elmhurst, Lombard, Bartlett, Oswego
Area Code 708
Cicero, Orland Park, Oak Lawn, Tinley Park, Berwyn, Oak Park, Calumet City, Burbank, Lansing, Oak Forest
Area Code 730
Belleville, O'fallon, Granite City, Edwardsville, Alton, Collinsville, Carbondale, East St. Louis, Godfrey, Marion
Area Code 773
Chicago, West Chicago
Area Code 779
Joliet, Rockford, Plainfield, Crystal Lake, Romeoville, Dekalb, Mchenry, New Lenox, Lockport, Woodstock
Area Code 815
Joliet, Rockford, Plainfield, Crystal Lake, Romeoville, Dekalb, Mchenry, New Lenox, Lockport, Woodstock
Area Code 847
Elgin, Waukegan, Schaumburg, Evanston, Arlington Heights, Skokie, Palatine, Des Plaines, Mount Prospect, Hoffman Estates
Area Code 861
Peoria, Bloomington, Normal, Moline, Romeoville, Rock Island, Pekin, Galesburg, East Peoria, Crest Hill
Area Code 872
Chicago
Major Cities Served by Illinois Area Codes
The most populous urban centers and census places covered by Illinois's area codes, ranked by population.
Illinois Area Code FAQs
Quick answers to common questions about Illinois telephone area codes.
How many area codes does Illinois have?
Illinois has 17 area codes: 217, 224, 309, 312, 331, 447, 464, 618, 630, 708, 730, 773, 779, 815, 847, 861, 872.
What timezone do Illinois area codes use?
Illinois area codes operate in the Central timezone.
What is the most populated area code in Illinois?
Area code 312 is the most populous prefix in Illinois based on covered city population.
Which Illinois area codes share an overlay?
217 and 447, 224 and 847, 309 and 861, 312 and 872, 331 and 630, 464 and 708, 618 and 730, 773 and 872, 779 and 815. Overlay codes serve the same area, which is why 10-digit dialing is required.
Are there scam area codes in Illinois?
Illinois has no area codes currently flagged as high-risk scams.
About Illinois Area Codes & Phone Dialing Rules
When placing calls within Illinois, ten-digit dialing (area code + 7-digit telephone number) is required in overlay regions where multiple area codes serve the same geographic boundaries.