Phone numbers in Claremont, California
Claremont has 58 phone prefixes in area codes 840, 909.
Biggest holders: Frontier, T-Mobile (including Sprint), Onvoy. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 17%
- Local phone company 36%
- Internet / business phone carrier 43%
- Paging service 3%
Every prefix in Claremont
Search the first six digits of a number in this list. If it's here, the number started in Claremont with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 840-205 | Bandwidth | Internet / business phone carrier | 2021 |
| 840-208 | Bandwidth | Internet / business phone carrier | 2022 |
| 840-229 | Verizon Wireless | Mobile carrier | 2023 |
| 840-236 | Onvoy | Internet / business phone carrier | 2023 |
| 840-277 | Verizon Wireless | Mobile carrier | 2025 |
| 840-804 | Onvoy | Internet / business phone carrier | 2023 |
| 840-977 | Fractel | Internet / business phone carrier | 2021 |
| 840-997 | Onvoy | Internet / business phone carrier | 2026 |
| 909-207 | Spok | Paging service | – |
| 909-267 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 909-288 | Onvoy | Internet / business phone carrier | – |
| 909-293 | MCImetro (Verizon Business) | Internet / business phone carrier | 2010 |
| 909-305 | Frontier | Local phone company | – |
| 909-344 | T-Mobile (including Sprint) | Mobile carrier | 2012 |
| 909-392 | Frontier | Local phone company | – |
| 909-394 | Frontier | Local phone company | – |
| 909-398 | Frontier | Local phone company | – |
| 909-399 | Frontier | Local phone company | – |
| 909-407 | MCImetro (Verizon Business) | Internet / business phone carrier | 2017 |
| 909-445 | Frontier | Local phone company | – |
| 909-447 | Frontier | Local phone company | – |
| 909-448 | Frontier | Local phone company | – |
| 909-450 | AT&T (local phone) | Local phone company | – |
| 909-451 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 909-480 | Frontier | Local phone company | – |
| 909-482 | Frontier | Local phone company | – |
| 909-506 | T-Mobile (including Sprint) | Mobile carrier | 2016 |
| 909-523 | Spok | Paging service | – |
| 909-526 | Verizon Wireless | Mobile carrier | 2024 |
| 909-541 | T-Mobile (including Sprint) | Mobile carrier | 2014 |
| 909-542 | Tpx Communications | Internet / business phone carrier | – |
| 909-568 | Tpx Communications | Internet / business phone carrier | – |
| 909-575 | Teleport Communications America | Internet / business phone carrier | – |
| 909-592 | Frontier | Local phone company | – |
| 909-593 | Frontier | Local phone company | – |
| 909-596 | Frontier | Local phone company | – |
| 909-599 | Frontier | Local phone company | – |
| 909-603 | Frontier | Local phone company | – |
| 909-607 | Teleport Communications America | Internet / business phone carrier | – |
| 909-621 | Frontier | Local phone company | – |
| 909-624 | Frontier | Local phone company | – |
| 909-625 | Frontier | Local phone company | – |
| 909-626 | Frontier | Local phone company | – |
| 909-656 | T-Mobile (including Sprint) | Mobile carrier | 2014 |
| 909-667 | Onvoy | Internet / business phone carrier | – |
| 909-670 | Tpx Communications | Internet / business phone carrier | – |
| 909-675 | Onvoy | Internet / business phone carrier | 2014 |
| 909-741 | T-Mobile (including Sprint) | Mobile carrier | 2015 |
| 909-753 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 909-788 | Fractel | Internet / business phone carrier | 2019 |
| 909-830 | Vonage America | Internet / business phone carrier | 2020 |
| 909-833 | Bandwidth | Internet / business phone carrier | 2010 |
| 909-901 | Bandwidth | Internet / business phone carrier | 2020 |
| 909-905 | T-Mobile (including Sprint) | Mobile carrier | 2020 |
| 909-929 | Charter / Spectrum | Internet / business phone carrier | 2013 |
| 909-962 | Teleport Communications America | Internet / business phone carrier | – |
| 909-964 | T-Mobile (including Sprint) | Mobile carrier | 2001 |
| 909-971 | Frontier | Local phone company | – |
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.