Phone numbers in Tremonton, Utah
Tremonton has 5 phone prefixes in area code 435.
Biggest holders: Frontier, T-Mobile (including Sprint), AT&T Mobility. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 40%
- Local phone company 40%
- Internet / business phone carrier 20%
Every prefix in Tremonton
Search the first six digits of a number in this list. If it's here, the number started in Tremonton with the carrier shown. If it isn't, check the Utah page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 435-207 | Frontier | Local phone company | – |
| 435-257 | Frontier | Local phone company | – |
| 435-282 | T-Mobile (including Sprint) | Mobile carrier | 2006 |
| 435-291 | AT&T Mobility | Mobile carrier | 2007 |
| 435-732 | Fractel | 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.