Phone numbers in San Mateo, California
San Mateo has 126 phone prefixes in area code 650.
Biggest holders: AT&T (local phone), AT&T Mobility, T-Mobile (including Sprint). This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 33%
- Local phone company 40%
- Internet / business phone carrier 25%
- Paging service 2%
- Phone company 1%
Every prefix in San Mateo
Search the first six digits of a number in this list. If it's here, the number started in San Mateo with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 650-200 | Twilio | Internet / business phone carrier | – |
| 650-202 | Utility Telecom Group | Phone company | – |
| 650-212 | AT&T (local phone) | Local phone company | – |
| 650-217 | Spok | Paging service | – |
| 650-218 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-222 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-227 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 650-235 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 650-240 | Onvoy | Internet / business phone carrier | – |
| 650-242 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 650-245 | AT&T Mobility | Mobile carrier | – |
| 650-274 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-281 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-286 | AT&T (local phone) | Local phone company | – |
| 650-287 | AT&T (local phone) | Local phone company | – |
| 650-288 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 650-292 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 650-293 | AT&T (local phone) | Local phone company | – |
| 650-294 | AT&T (local phone) | Local phone company | – |
| 650-295 | AT&T (local phone) | Local phone company | – |
| 650-312 | AT&T (local phone) | Local phone company | – |
| 650-315 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-340 | AT&T (local phone) | Local phone company | – |
| 650-341 | AT&T (local phone) | Local phone company | – |
| 650-342 | AT&T (local phone) | Local phone company | – |
| 650-343 | AT&T (local phone) | Local phone company | – |
| 650-344 | AT&T (local phone) | Local phone company | – |
| 650-345 | AT&T (local phone) | Local phone company | – |
| 650-346 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-347 | AT&T (local phone) | Local phone company | – |
| 650-348 | AT&T (local phone) | Local phone company | – |
| 650-349 | AT&T (local phone) | Local phone company | – |
| 650-350 | AT&T (local phone) | Local phone company | – |
| 650-356 | AT&T (local phone) | Local phone company | – |
| 650-357 | AT&T (local phone) | Local phone company | – |
| 650-358 | AT&T (local phone) | Local phone company | – |
| 650-371 | Spok | Paging service | – |
| 650-372 | AT&T (local phone) | Local phone company | – |
| 650-373 | AT&T (local phone) | Local phone company | – |
| 650-375 | AT&T (local phone) | Local phone company | – |
| 650-376 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 650-377 | AT&T (local phone) | Local phone company | – |
| 650-378 | AT&T (local phone) | Local phone company | – |
| 650-389 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 650-393 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 650-398 | Verizon Wireless | Mobile carrier | 2018 |
| 650-401 | AT&T (local phone) | Local phone company | – |
| 650-403 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 650-418 | Verizon Wireless | Mobile carrier | 2019 |
| 650-425 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 650-430 | T-Mobile (including Sprint) | Mobile carrier | 2001 |
| 650-431 | T-Mobile (including Sprint) | Mobile carrier | 2015 |
| 650-432 | AT&T (local phone) | Local phone company | – |
| 650-435 | Verizon Wireless | Mobile carrier | 2015 |
| 650-436 | AT&T Mobility | Mobile carrier | 2015 |
| 650-437 | Bandwidth | Internet / business phone carrier | 2014 |
| 650-445 | T-Mobile (including Sprint) | Mobile carrier | 2013 |
| 650-458 | Astound Broadband | Internet / business phone carrier | – |
| 650-477 | Verizon Wireless | Mobile carrier | – |
| 650-483 | AT&T Mobility | Mobile carrier | – |
| 650-484 | AT&T Mobility | Mobile carrier | 2016 |
| 650-504 | AT&T Mobility | Mobile carrier | – |
| 650-513 | AT&T (local phone) | Local phone company | – |
| 650-514 | Level 3 (Lumen) | Internet / business phone carrier | 2019 |
| 650-520 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-522 | AT&T (local phone) | Local phone company | – |
| 650-523 | Onvoy | Internet / business phone carrier | – |
| 650-524 | AT&T (local phone) | Local phone company | – |
| 650-525 | AT&T (local phone) | Local phone company | – |
| 650-532 | Tpx Communications | Internet / business phone carrier | – |
| 650-533 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 650-539 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-541 | AT&T Mobility | Mobile carrier | 2022 |
| 650-544 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-548 | AT&T (local phone) | Local phone company | – |
| 650-554 | AT&T (local phone) | Local phone company | – |
| 650-558 | AT&T (local phone) | Local phone company | – |
| 650-570 | AT&T (local phone) | Local phone company | – |
| 650-571 | AT&T (local phone) | Local phone company | – |
| 650-572 | AT&T (local phone) | Local phone company | – |
| 650-573 | AT&T (local phone) | Local phone company | – |
| 650-574 | AT&T (local phone) | Local phone company | – |
| 650-576 | AT&T Mobility | Mobile carrier | – |
| 650-577 | AT&T (local phone) | Local phone company | – |
| 650-578 | AT&T (local phone) | Local phone company | – |
| 650-579 | AT&T (local phone) | Local phone company | – |
| 650-581 | Teleport Communications America | Internet / business phone carrier | – |
| 650-612 | AT&T (local phone) | Local phone company | – |
| 650-619 | AT&T Mobility | Mobile carrier | – |
| 650-627 | AT&T (local phone) | Local phone company | – |
| 650-629 | Fractel | Internet / business phone carrier | 2021 |
| 650-638 | AT&T (local phone) | Local phone company | – |
| 650-639 | AT&T Mobility | Mobile carrier | 2024 |
| 650-642 | T-Mobile (including Sprint) | Mobile carrier | – |
| 650-645 | Teleport Communications America | Internet / business phone carrier | – |
| 650-650 | Onvoy | Internet / business phone carrier | 2022 |
| 650-653 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 650-655 | AT&T (local phone) | Local phone company | – |
| 650-659 | Onvoy | Internet / business phone carrier | 2025 |
| 650-667 | AT&T Mobility | Mobile carrier | 2014 |
| 650-678 | Verizon Wireless | Mobile carrier | – |
| 650-685 | AT&T (local phone) | Local phone company | – |
| 650-696 | AT&T (local phone) | Local phone company | – |
| 650-699 | Fractel | Internet / business phone carrier | 2019 |
| 650-703 | AT&T Mobility | Mobile carrier | – |
| 650-706 | Onvoy | Internet / business phone carrier | 2023 |
| 650-715 | Onvoy | Internet / business phone carrier | 2022 |
| 650-727 | Bandwidth | Internet / business phone carrier | 2014 |
| 650-740 | AT&T Mobility | Mobile carrier | – |
| 650-753 | T-Mobile (including Sprint) | Mobile carrier | 2014 |
| 650-759 | Verizon Wireless | Mobile carrier | – |
| 650-762 | AT&T (local phone) | Local phone company | – |
| 650-766 | AT&T Mobility | Mobile carrier | – |
| 650-773 | Verizon Wireless | Mobile carrier | 2001 |
| 650-778 | Onvoy | Internet / business phone carrier | 2026 |
| 650-781 | Bandwidth | Internet / business phone carrier | – |
| 650-787 | AT&T Mobility | Mobile carrier | – |
| 650-844 | Fractel | Internet / business phone carrier | 2020 |
| 650-863 | AT&T Mobility | Mobile carrier | – |
| 650-865 | AT&T Mobility | Mobile carrier | 2016 |
| 650-867 | AT&T Mobility | Mobile carrier | – |
| 650-888 | AT&T Mobility | Mobile carrier | – |
| 650-918 | AT&T (local phone) | Local phone company | – |
| 650-921 | MetroPCS (T-Mobile) | Mobile carrier | 2001 |
| 650-931 | Tpx Communications | Internet / business phone carrier | – |
| 650-954 | T-Mobile (including Sprint) | 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.