Illinois Area Codes

17 area codes assigned to Illinois · Central Time

Which Illinois Area Code Covers Where

5 of Illinois's area codes share territory with another. Codes in the same row serve the same places, so either can reach a number there — and ten-digit dialling is required throughout.

  • 217+447· Alexander, Alvin, Arcola, Arenzville +261 more
  • 224+847· Algonquin, Antioch, Arlington Heights, Barrington +37 more
  • 331+630· Aurora, Bartlett, Bensenville, Big Rock +18 more
  • 464+708· Beecher, Bellwood, Blue Island, Calumet City +15 more
  • 779+815· Ashton, Beaverville, Belvidere, Braidwood +135 more

The remaining 7 codes cover their own area: 309, 312, 618, 730, 773, 861, 872.

How Illinois Got Its Area Codes

Illinois went from 4 area codes in 1947 to 17 today. A split carves territory off its parent; an overlay sits on top of it, which is why newer codes need ten-digit dialling.

  1. 1947217one of the original 1947 area codes
  2. 1947312one of the original 1947 area codes
  3. 1947618one of the original 1947 area codes
  4. 1947815one of the original 1947 area codes
  5. 1957309in service; no parent code on record
  6. 1989708split from 312
  7. 1996847split from 708
  8. 1996630split from 708
  9. 1996773split from 312
  10. 2002224overlaid 847
  11. 2007779overlaid 815
  12. 2007331overlaid 630
  13. 2009872overlaid 312
  14. 2021447overlaid 217
  15. 2022464overlaid 708
  16. 2023861overlaid 309
  17. 2023730overlaid 618

Dates from the NANPA area code report, 09/19/2026.

Illinois Call Routing Regions

Illinois spans 18 LATAs — the regions a call is routed within before it becomes long-haul.

217

Illinois

Central Time

Overlay · with 447

5,339 blocks · 265 rate centres

224

Illinois

Central Time

Overlay · with 847

6,160 blocks · 41 rate centres

309

Illinois

Central Time

5,250 blocks · 171 rate centres

312

Illinois

Central Time

4,666 blocks · 15 rate centres

331

Illinois

Central Time

Overlay · with 630

2,314 blocks · 22 rate centres

447

Illinois

Central Time

Overlay · with 217

1,434 blocks · 119 rate centres

464

Illinois

Central Time

Overlay · with 708

1,112 blocks · 19 rate centres

618

Illinois

Central Time

6,067 blocks · 243 rate centres

630

Illinois

Central Time

Overlay · with 331

5,018 blocks · 37 rate centres

708

Illinois

Central Time

Overlay · with 464

5,814 blocks · 36 rate centres

730

Illinois

Central Time

985 blocks · 64 rate centres

773

Illinois

Central Time

5,360 blocks · 27 rate centres

779

Illinois

Central Time

Overlay · with 815

2,897 blocks · 139 rate centres

815

Illinois

Central Time

Overlay · with 779

5,552 blocks · 203 rate centres

847

Illinois

Central Time

Overlay · with 224

4,696 blocks · 50 rate centres

861

Illinois

Central Time

0 blocks · 0 rate centres

872

Illinois

Central Time

2,916 blocks · 11 rate centres

Which Illinois Area Code Covers a City?

Illinois has more than one area code in most regions. Enter a city to see which codes serve it, or check a specific number instead.

Illinois Numbering Structure

Recent Overlays — Ten-Digit Dialing

Illinois has had 10 area codes activated as an overlay since 2021, sharing territory with an existing code rather than carving out new geography. Local calls in an overlaid region must be dialed with all ten digits. Earlier overlays are not listed here.

See every North American overlay

About Illinois area codes

Illinois is served by 17 area codes in the North American Numbering Plan (NANP): 217, 224, 309, 312, 331, 447, 464, 618, 630, 708, 730, 773, 779, 815, 847, 861, 872. All Illinois numbers are in the Central Time zone. Click any area code above to see the cities and rate centers it covers, formatted tel: link examples, and to search for available phone numbers.