Area code 861 – Illinois
861 has served Illinois since 2023, split from 309. It is still largely empty: 8 of 786 number blocks allocated. Other CLEC / VoIP holds 75.0% of those blocks, which is unusually concentrated for a US area code. It shares its geography with overlay codes 309, so local calls take all ten digits.
Who holds 861 number blocks
Share of the 8 assigned NXX blocks (1% of the 786 possible), across 6 carriers. This is share of number blocks, not of subscribers.
- Other CLEC / VoIP75%
- Onvoy12.5%
- 8x812.5%
Rate centers in 861
NANPA allocates number blocks to rate centers and records their names abbreviated to ten characters, so these are NANPA's codes rather than place names – CHAMPAURBN is Champaign-Urbana, NWYRCYZN01 is a New York City zone. We show them unchanged instead of guessing at the full names.
Timeline
- 2023 861 goes into service, split from or overlaid on 309.
More about 861
Separate pages for the questions that need their own answer: what time it is there, what the complaint data says, who holds the number blocks, and how the code compares with the one it shares its area with.
Frequently asked about 861
What state is area code 861?
Illinois. It covers the same area as 309/861.
Which carrier owns 861 numbers?
Other CLEC / VoIP holds the largest share of assigned number blocks at 75.0%. The rest is spread across 2 other carriers. This is share of number blocks, not of subscribers – people keep their numbers when they switch carriers.
Do I need to dial 10 digits in 861?
Yes – ten digits for local calls in 861, because it shares its area with another code.
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
NANPA dialing note for this code: “10D”. Reviewed by the data desk. Spotted an error? Request a correction.