Phone numbers in Simi Valley, California
Simi Valley has 46 phone prefixes in area codes 805, 820.
Biggest holders: AT&T (local phone), Verizon Wireless, Onvoy. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 30%
- Local phone company 33%
- Internet / business phone carrier 37%
Every prefix in Simi Valley
Search the first six digits of a number in this list. If it's here, the number started in Simi Valley with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 805-206 | Verizon Wireless | Mobile carrier | 2010 |
| 805-210 | Tpx Communications | Internet / business phone carrier | 2006 |
| 805-251 | Peerless Network Of California | Internet / business phone carrier | 2012 |
| 805-261 | Charter / Spectrum | Internet / business phone carrier | 2016 |
| 805-285 | Charter / Spectrum | Internet / business phone carrier | 2008 |
| 805-297 | Verizon Wireless | Mobile carrier | – |
| 805-304 | T-Mobile (including Sprint) | Mobile carrier | 2002 |
| 805-306 | AT&T (local phone) | Local phone company | – |
| 805-327 | Peerless Network Of California | Internet / business phone carrier | 2012 |
| 805-328 | Bandwidth | Internet / business phone carrier | 2010 |
| 805-362 | Onvoy | Internet / business phone carrier | 2023 |
| 805-387 | Verizon Wireless | Mobile carrier | 2013 |
| 805-404 | AT&T Mobility | Mobile carrier | – |
| 805-416 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 805-422 | MetroPCS (T-Mobile) | Mobile carrier | 2014 |
| 805-424 | T-Mobile (including Sprint) | Mobile carrier | 2018 |
| 805-426 | AT&T (local phone) | Local phone company | – |
| 805-428 | AT&T Mobility | Mobile carrier | 2001 |
| 805-433 | MCImetro (Verizon Business) | Internet / business phone carrier | 2001 |
| 805-501 | AT&T Mobility | Mobile carrier | – |
| 805-520 | AT&T (local phone) | Local phone company | – |
| 805-522 | AT&T (local phone) | Local phone company | – |
| 805-526 | AT&T (local phone) | Local phone company | – |
| 805-527 | AT&T (local phone) | Local phone company | – |
| 805-537 | Peerless Network Of California | Internet / business phone carrier | 2012 |
| 805-577 | AT&T (local phone) | Local phone company | – |
| 805-578 | AT&T (local phone) | Local phone company | – |
| 805-579 | AT&T (local phone) | Local phone company | – |
| 805-581 | AT&T (local phone) | Local phone company | – |
| 805-582 | AT&T (local phone) | Local phone company | – |
| 805-583 | AT&T (local phone) | Local phone company | – |
| 805-584 | AT&T (local phone) | Local phone company | – |
| 805-587 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 805-624 | Level 3 (Lumen) | Internet / business phone carrier | 2001 |
| 805-629 | AT&T (local phone) | Local phone company | – |
| 805-638 | Verizon Wireless | Mobile carrier | – |
| 805-791 | Verizon Wireless | Mobile carrier | 2006 |
| 805-813 | AT&T Mobility | Mobile carrier | – |
| 805-823 | Onvoy | Internet / business phone carrier | – |
| 805-842 | Onvoy | Internet / business phone carrier | – |
| 805-864 | Verizon Wireless | Mobile carrier | 2015 |
| 805-915 | Tpx Communications | Internet / business phone carrier | – |
| 805-955 | AT&T (local phone) | Local phone company | – |
| 820-386 | Fractel | Internet / business phone carrier | 2022 |
| 820-502 | Onvoy | Internet / business phone carrier | 2023 |
| 820-888 | Terra Nova Telecom | Internet / business phone carrier | 2018 |
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.