Phone numbers in Rialto, California
Rialto has 39 phone prefixes in area codes 840, 909.
Biggest holders: AT&T (local phone), Bandwidth, MetroPCS (T-Mobile). This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 28%
- Local phone company 21%
- Internet / business phone carrier 49%
- Phone company 3%
Every prefix in Rialto
Search the first six digits of a number in this list. If it's here, the number started in Rialto with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 840-220 | Bandwidth | Internet / business phone carrier | 2022 |
| 840-241 | Onvoy | Internet / business phone carrier | 2023 |
| 840-254 | Onvoy | Internet / business phone carrier | 2024 |
| 840-799 | Fractel | Internet / business phone carrier | 2021 |
| 840-900 | Fractel | Internet / business phone carrier | 2020 |
| 909-233 | MetroPCS (T-Mobile) | Mobile carrier | 2007 |
| 909-237 | Verizon Wireless | Mobile carrier | – |
| 909-258 | MetroPCS (T-Mobile) | Mobile carrier | 2008 |
| 909-265 | MetroPCS (T-Mobile) | Mobile carrier | 2009 |
| 909-271 | Onvoy | Internet / business phone carrier | 2009 |
| 909-301 | Bandwidth | Internet / business phone carrier | 2011 |
| 909-341 | Charter / Spectrum | Internet / business phone carrier | 2012 |
| 909-419 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 909-421 | AT&T (local phone) | Local phone company | – |
| 909-440 | Verizon Wireless | Mobile carrier | – |
| 909-442 | T-Mobile (including Sprint) | Mobile carrier | 2016 |
| 909-543 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 909-546 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 909-562 | AT&T (local phone) | Local phone company | – |
| 909-566 | Bandwidth | Internet / business phone carrier | 2015 |
| 909-586 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 909-640 | AT&T Enterprises | Phone company | 2016 |
| 909-644 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 909-666 | Bandwidth | Internet / business phone carrier | – |
| 909-676 | MetroPCS (T-Mobile) | Mobile carrier | 2014 |
| 909-685 | AT&T Mobility | Mobile carrier | 2006 |
| 909-745 | T-Mobile (including Sprint) | Mobile carrier | 2015 |
| 909-746 | Tpx Communications | Internet / business phone carrier | – |
| 909-787 | Onvoy | Internet / business phone carrier | 2016 |
| 909-820 | AT&T (local phone) | Local phone company | – |
| 909-873 | AT&T (local phone) | Local phone company | – |
| 909-874 | AT&T (local phone) | Local phone company | – |
| 909-875 | AT&T (local phone) | Local phone company | – |
| 909-877 | AT&T (local phone) | Local phone company | – |
| 909-879 | AT&T (local phone) | Local phone company | – |
| 909-955 | MetroPCS (T-Mobile) | Mobile carrier | 2018 |
| 909-961 | T-Mobile (including Sprint) | Mobile carrier | 2005 |
| 909-990 | Charter / Spectrum | Internet / business phone carrier | 2013 |
| 909-999 | Bandwidth | 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.