Phone numbers in Thermopolis, Wyoming
Thermopolis has 4 phone prefixes in area code 307.
Biggest holders: AT&T Mobility, Union Telephone, Rt Communications. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 50%
- Local phone company 25%
- Phone company 25%
Every prefix in Thermopolis
Search the first six digits of a number in this list. If it's here, the number started in Thermopolis with the carrier shown. If it isn't, check the Wyoming page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 307-480 | AT&T Mobility | Mobile carrier | 2005 |
| 307-722 | Union Telephone | Local phone company | 2002 |
| 307-864 | Rt Communications | Phone company | – |
| 307-921 | Verizon Wireless | 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.