Illinois area codes
Illinois uses 17 area codes. The oldest is 217, in service since 1947; the newest is 730, from 2023. Across them 8,991 of 13,362 possible number blocks are allocated, 67.3% of capacity. 217, 309, 618, 773, 815, 847, 312, 708 and 630 are at or past 95%, which is why new numbers there come from overlays rather than the original code. AT&T holds 36.8% of the 8,991 assigned blocks across the state, ahead of T-Mobile at 11.3%; a further 11.3% sits with CLEC and VoIP holders outside the national carriers. In the 33 days to 30 October 2026, FTC complaints named an Illinois caller ID 10,481 times – 4.6% of all complaints in the window, most often 217 with 2,562 (1st of 422 nationally). NANPA records 1,440 rate centers across the state's codes.
All 17 codes
| Code | In service | Blocks used | Largest holder | Complaints | Shares area with |
|---|---|---|---|---|---|
| 217 | 1947 | 786/786 | AT&T 27.9% | 2,562 | 447 |
| 224 | 2002 | 595/786 | AT&T 25.5% | 667 | 847 |
| 309 | 1957 | 786/786 | Other CLEC / VoIP 23.5% | 322 | 861 |
| 312 | 1947 | 784/786 | AT&T 56.4% | 494 | 872 |
| 331 | 2007 | 224/786 | T-Mobile 19.2% | 591 | 630 |
| 447 | 2021 | 221/786 | Other CLEC / VoIP 36.2% | 144 | 217 |
| 464 | 2022 | 112/786 | AT&T 52.7% | 177 | 708 |
| 618 | 1947 | 786/786 | AT&T 28.6% | 848 | 730 |
| 630 | 1996 | 782/786 | AT&T 54% | 844 | 331 |
| 708 | 1989 | 784/786 | AT&T 41.1% | 963 | 464 |
| 730 | 2023 | 130/786 | AT&T 45.4% | 37 | 618 |
| 773 | 1996 | 786/786 | AT&T 46.3% | 667 | 872 |
| 779 | 2007 | 354/786 | Other CLEC / VoIP 33.3% | 194 | 815 |
| 815 | 1947 | 786/786 | AT&T 28.9% | 915 | 779 |
| 847 | 1996 | 786/786 | AT&T 63.4% | 550 | 224 |
| 861 | 2023 | 8/786 | Other CLEC / VoIP 75% | – | 309 |
| 872 | 2009 | 281/786 | T-Mobile 26% | 506 | 312, 773 |
Block share is share of allocated number blocks, not of subscribers. Complaint counts cover 28 Sep – 30 Oct 2026 and reflect spoofed caller IDs as much as real calls.
How full Illinois’s codes are
A code holds at most 786 blocks of 10,000 numbers each. When a code fills up, the administrator does not reclaim numbers – it adds an overlay, and from then on new numbers in the same area come from the new code.
Full or nearly full
Who holds the number blocks
Counted from every assigned block in the state: 8,991 blocks, each with the holder NANPA recorded for it. Percentages are measured, not estimated.
| Holder | Blocks | Share of Illinois | Largest in |
|---|---|---|---|
| AT&T | 3,308 | 36.8% | 11 codes |
| Other CLEC / VoIP | 1,018 | 11.3% | 4 codes |
| T-Mobile | 1,015 | 11.3% | 2 codes |
| Verizon | 964 | 10.7% | – |
| Frontier | 663 | 7.4% | – |
| Lumen | 552 | 6.1% | – |
| Onvoy | 518 | 5.8% | – |
| Windstream | 204 | 2.3% | – |
| Bandwidth | 145 | 1.6% | – |
| Spok | 112 | 1.2% | – |
| Comcast | 92 | 1% | – |
| Charter | 85 | 0.9% | – |
“Other CLEC / VoIP” is not one company: it is every holder outside the national carriers counted together, which is what resellers and app-based numbers look like in the records. This is allocation, not subscribers.
Spam complaints naming Illinois codes
FTC Do Not Call complaints where the caller ID shown was a Illinois number, 28 Sep – 30 Oct 2026 (33 days). Caller IDs on spam calls are routinely faked, so these are complaints about the code, not calls proven to come from it.
| Code | Complaints | National rank |
|---|---|---|
| 217 | 2,562 | #1 of 422 |
| 708 | 963 | #45 of 422 |
| 815 | 915 | #58 of 422 |
| 618 | 848 | #81 of 422 |
| 630 | 844 | #84 of 422 |
What people said the calls were about
- Reducing your debt (credit cards, mortgage, student loans) – 1,286
- Other – 1,178
- Calls pretending to be government, businesses, or family and friends – 247
- Dropped call or no message – 91
Topics as the complainant chose them, for the codes where the FTC published a topic.
How Illinois got its codes
4 in the 1940s, 1 in the 1950s, 1 in the 1980s, 3 in the 1990s, 4 in the 2000s, 4 in the 2020s. Each code after the first was split off from or overlaid on one already in service.
- 1947 217 goes into service.
- 1947 312 goes into service.
- 1947 618 goes into service.
- 1947 815 goes into service.
- 1957 309 goes into service.
- 1989 708 goes into service, split from or overlaid on 312.
- 1996 630 goes into service, split from or overlaid on 708.
- 1996 773 goes into service, split from or overlaid on 312.
- 1996 847 goes into service, split from or overlaid on 708.
- 2002 224 goes into service, split from or overlaid on 847.
- 2007 331 goes into service, split from or overlaid on 630.
- 2007 779 goes into service, split from or overlaid on 815.
- 2009 872 goes into service, split from or overlaid on 312.
- 2021 447 goes into service, split from or overlaid on 217.
- 2022 464 goes into service, split from or overlaid on 708.
- 2023 730 goes into service, split from or overlaid on 618.
- 2023 861 goes into service, split from or overlaid on 309.
Time zones
Illinois is in Central time.
Frequently asked about Illinois area codes
How many area codes does Illinois have?
17 in service. They are 217, 224, 309, 312, 331, 447, 464, 618, 630, 708, 730, 773, 779, 815, 847, 861 and 872.
What is the oldest area code in Illinois?
217, in service since 1947. Every later code in the state was split off from or overlaid on an existing one.
What is the newest area code in Illinois?
730, from 2023, overlaying 618.
Is Illinois running out of numbers?
217, 309, 618, 773, 815, 847, 312, 708 and 630 are at or past 95% of capacity, but NANPA has not opened relief planning for them, so no new code is announced.
What time zone is Illinois in?
Central time.
Which Illinois area code gets the most spam complaints?
217 – 2,562 FTC complaints in the 33 days to 30 October 2026, 1st of 422 codes nationally. Those are complaints about the caller ID shown, and spam callers routinely fake a local-looking number, so this says the code is imitated often, not that the calls come from there.
Which carrier holds the most Illinois numbers?
AT&T, with 36.8% of the 8,991 blocks assigned across Illinois, ahead of Other CLEC / VoIP at 11.3%. This is allocation of blocks by the numbering administrator, not a count of subscribers – people keep their numbers when they switch carriers.
Sources and verification
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- NANPA – CO Code Assignment Records, All States (utilized), file updated 11/01/2026, retrieved Nov 1, 2026
- FTC – Do Not Call Reported Calls Data, 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
Figures on this page are counted from those files, not copied from other sites. Spotted an error? Request a correction. How we collect and check: methodology.