Phone numbers in Columbia, Illinois
Columbia has 4 phone prefixes in area codes 618, 730.
Biggest holders: Harrisonville Tel, Teleport Communications America, T-Mobile (including Sprint). This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 25%
- Internet / business phone carrier 50%
- Phone company 25%
Every prefix in Columbia
Search the first six digits of a number in this list. If it's here, the number started in Columbia with the carrier shown. If it isn't, check the Illinois page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 618-281 | Harrisonville Tel | Phone company | – |
| 618-470 | Teleport Communications America | Internet / business phone carrier | 2019 |
| 618-719 | T-Mobile (including Sprint) | Mobile carrier | 2001 |
| 730-293 | Level 3 (Lumen) | Internet / business phone carrier | 2026 |
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.