Phone numbers in Columbia, Connecticut
Columbia has 5 phone prefixes in area codes 860, 959.
Biggest holders: MCImetro (Verizon Business), AT&T (local phone), Comcast. This is the local calling area (rate center) where those prefixes were first assigned.
- Local phone company 20%
- Internet / business phone carrier 80%
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 Connecticut page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 860-228 | AT&T (local phone) | Local phone company | – |
| 860-337 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 860-359 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 860-530 | Comcast | Internet / business phone carrier | – |
| 959-510 | Onvoy | Internet / business phone carrier | 2021 |
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.