Phone numbers in Orinda, California
Orinda has 12 phone prefixes in area code 925.
Biggest holders: MCImetro (Verizon Business), AT&T (local phone), Bandwidth. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 8%
- Local phone company 25%
- Internet / business phone carrier 67%
Every prefix in Orinda
Search the first six digits of a number in this list. If it's here, the number started in Orinda with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 925-253 | AT&T (local phone) | Local phone company | – |
| 925-254 | AT&T (local phone) | Local phone company | – |
| 925-255 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 925-257 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 925-258 | AT&T (local phone) | Local phone company | – |
| 925-259 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 925-317 | Bandwidth | Internet / business phone carrier | – |
| 925-386 | Teleport Communications America | Internet / business phone carrier | – |
| 925-402 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 925-438 | Tpx Communications | Internet / business phone carrier | – |
| 925-528 | T-Mobile (including Sprint) | Mobile carrier | – |
| 925-885 | Matrix Telecom, Llc. S/i/i Tnci | Internet / business phone 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.