Phone numbers in Hardin, Montana
Hardin has 7 phone prefixes in area code 406.
Biggest holders: Commio, Onvoy, Project Tel. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 29%
- Local phone company 14%
- Internet / business phone carrier 43%
- Phone company 14%
Every prefix in Hardin
Search the first six digits of a number in this list. If it's here, the number started in Hardin with the carrier shown. If it isn't, check the Montana page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 406-623 | Commio | Internet / business phone carrier | – |
| 406-629 | Onvoy | Internet / business phone carrier | – |
| 406-638 | Project Tel | Phone company | – |
| 406-665 | CenturyLink / Lumen | Local phone company | – |
| 406-679 | Nuso | Internet / business phone carrier | – |
| 406-699 | AT&T Mobility | Mobile carrier | – |
| 406-953 | Sagebrush Cellular | Mobile carrier | – |
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.