Illinois Area Codes
16 active area codes · Chicago · Population around 12,703,033
Illinois has 16 active area codes, serving cities like Chicago, Aurora, and Naperville. Of those, 16 are overlays covering ground another code already covers, which is why local calls there use all ten digits. The newest, 730, has been in service since July 7, 2023. Each code below links to its cities, carriers, timezone, and coverage map.
Illinois Area Code Map
What area codes does Illinois have?
- 217OverlaySpringfieldCentral Time (CT) · 326 cities · 1,101,437
- 224OverlayElginCentral Time (CT) · 108 cities · 2,005,752
- 309OverlayPeoriaCentral Time (CT) · 203 cities · 899,606
- 312OverlayChicagoCentral Time (CT) · 1 city · 348,013
- 331OverlayAuroraCentral Time (CT) · 61 cities · 1,703,350
- 447OverlaySpringfieldCentral Time (CT) · 326 cities · 1,101,437
- 464OverlayCiceroCentral Time (CT) · 93 cities · 1,486,972
- 618OverlayBellevilleCentral Time (CT) · 329 cities · 1,202,793
- 630OverlayAuroraCentral Time (CT) · 61 cities · 1,703,350
- 708OverlayCiceroCentral Time (CT) · 93 cities · 1,486,972
- 730OverlayBellevilleCentral Time (CT) · 329 cities · 1,202,793
- 773OverlayChicagoCentral Time (CT) · 1 city · 2,367,030
- 779OverlayRockfordCentral Time (CT) · 275 cities · 1,697,555
- 815OverlayRockfordCentral Time (CT) · 275 cities · 1,697,555
- 847OverlayElginCentral Time (CT) · 108 cities · 2,005,752
- 872OverlayChicagoCentral Time (CT) · 1 city · 2,715,043
More than one of these codes covers 90 of the 102 counties in Illinois, and one county is covered by 11 of them. Each card counts the people inside that code's own boundary at the 2020 census. Adding all 16 gives 24,725,410, against the 12,812,508 the same census counts in those counties, because 11,912,902 residents fall inside more than one code.
Which cities are the largest in Illinois?
How many phone prefixes does Illinois use?
The area codes in Illinois hold 8,366 assigned prefixes between them, listed under 145 distinct carrier names. A prefix is the three digits after the area code, and NANPA assigns each one to a single carrier. One of the 16 codes here — 730 — is newer than the NANPA extract behind these numbers, so its prefixes are not counted above.
Sources: City populations – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). State populations – the same program, Vintage 2025 (CO-EST2025-ALLDATA). Area-code footprint and county populations – 2020 Census Centers of Population, mapped against NANP area code boundaries. The share of each city inside a code is measured the same way, against Census place boundaries from the Census Bureau's TIGERweb service. Area code assignments – NANPA CO Code data. See our data methodology.
Frequently Asked Questions
How many area codes does Illinois have?
Illinois has 16 active area codes: 217, 224, 309, 312, 331, 447, 464, 618, 630, 708, 730, 773, 779, 815, 847, 872.
What is the main area code for Illinois?
Of the 16 area codes in Illinois, 312 is the oldest one still serving Chicago, its largest city. 312 has been in service since 1947.
What are the largest cities in Illinois?
The largest cities in Illinois include Chicago, Aurora, Naperville, Joliet, Rockford.
What is the total population of Illinois?
Illinois has an estimated total population of 12,703,033 based on US Census PEP 2024 data.
Do I have to dial ten digits in Illinois?
In the parts of Illinois covered by an overlay, yes. 16 of the 16 area codes here cover ground another code already covers, and where two codes share an area, local calls need the area code as well as the seven-digit number.
Why does Illinois have 16 area codes?
They arrived one at a time rather than all at once: 312 has been in service since 1947. 16 of the 16 are overlays, laid over a code that already covered the same ground instead of splitting its map in two. The most recent is 730, in service since July 7, 2023.
What is the newest area code in Illinois?
730, in service since July 7, 2023.
Is my county covered by more than one area code in Illinois?
It may be: more than one area code covers 90 of the 102 counties in Illinois, and one county there is covered by 11 of them. The table above shows which codes reach each of the largest cities.