Phone numbers in Healdsburg, California
Healdsburg has 10 phone prefixes in area codes 369, 707.
Biggest holders: AT&T (local phone), T-Mobile (including Sprint), Onvoy. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 30%
- Local phone company 30%
- Internet / business phone carrier 40%
Every prefix in Healdsburg
Search the first six digits of a number in this list. If it's here, the number started in Healdsburg with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 369-213 | T-Mobile (including Sprint) | Mobile carrier | 2023 |
| 369-238 | Onvoy | Internet / business phone carrier | 2025 |
| 707-385 | Allstream | Internet / business phone carrier | 2001 |
| 707-395 | Teleport Communications America | Internet / business phone carrier | – |
| 707-431 | AT&T (local phone) | Local phone company | – |
| 707-433 | AT&T (local phone) | Local phone company | – |
| 707-473 | AT&T (local phone) | Local phone company | – |
| 707-723 | Onvoy | Internet / business phone carrier | – |
| 707-756 | T-Mobile (including Sprint) | Mobile carrier | – |
| 707-955 | AT&T Mobility | 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.