Phone numbers in West Chicago, Illinois
West Chicago has 28 phone prefixes in area codes 331, 630.
Biggest holders: AT&T Mobility, AT&T (local phone), Onvoy. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 43%
- Local phone company 14%
- Internet / business phone carrier 39%
- Phone company 4%
Every prefix in West Chicago
Search the first six digits of a number in this list. If it's here, the number started in West Chicago with the carrier shown. If it isn't, check the Illinois page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 331-232 | AT&T Mobility | Mobile carrier | 2017 |
| 331-240 | Peerless Network Of Illinois | Internet / business phone carrier | 2013 |
| 331-344 | Onvoy | Internet / business phone carrier | 2026 |
| 331-465 | AT&T Mobility | Mobile carrier | 2007 |
| 331-703 | T-Mobile (including Sprint) | Mobile carrier | 2013 |
| 331-800 | Onvoy | Internet / business phone carrier | 2017 |
| 331-837 | TON80 Communications | Internet / business phone carrier | 2022 |
| 331-871 | Onvoy | Internet / business phone carrier | 2016 |
| 630-206 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 630-231 | AT&T (local phone) | Local phone company | – |
| 630-234 | AT&T Mobility | Mobile carrier | – |
| 630-251 | AT&T Mobility | Mobile carrier | – |
| 630-293 | AT&T (local phone) | Local phone company | – |
| 630-346 | AT&T Mobility | Mobile carrier | – |
| 630-386 | AT&T Mobility | Mobile carrier | 2005 |
| 630-414 | AT&T Mobility | Mobile carrier | 2006 |
| 630-440 | T-Mobile (including Sprint) | Mobile carrier | 2001 |
| 630-473 | Comcast | Internet / business phone carrier | 2009 |
| 630-520 | Teleport Communications America | Internet / business phone carrier | – |
| 630-562 | AT&T (local phone) | Local phone company | – |
| 630-621 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 630-639 | Windstream (PAETEC) | Internet / business phone carrier | 2001 |
| 630-779 | AT&T Mobility | Mobile carrier | – |
| 630-815 | AT&T Mobility | Mobile carrier | 2007 |
| 630-818 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 630-876 | AT&T (local phone) | Local phone company | – |
| 630-877 | AT&T Mobility | Mobile carrier | 2006 |
| 630-957 | First Communications | Phone company | 2004 |
Most prefixes are pooled: the 10,000 numbers in each are handed out in blocks of 1,000 to different carriers, and people can also take their numbers to another carrier. So the carrier shown is where the prefix started, not a guarantee about any one number. Source: NANPA central office code records, 2026-10-10.