Phone numbers in Delano, California
Delano has 23 phone prefixes in area code 661.
Biggest holders: T-Mobile (including Sprint), AT&T (local phone), AT&T Mobility. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 35%
- Local phone company 17%
- Internet / business phone carrier 43%
- Phone company 4%
Every prefix in Delano
Search the first six digits of a number in this list. If it's here, the number started in Delano with the carrier shown. If it isn't, check the California page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 661-229 | AT&T Mobility | Mobile carrier | – |
| 661-359 | Utility Telecom Group | Phone company | – |
| 661-370 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 661-372 | Bandwidth | Internet / business phone carrier | 2014 |
| 661-375 | Verizon Wireless | Mobile carrier | – |
| 661-446 | Teleport Communications America | Internet / business phone carrier | 2012 |
| 661-454 | Bhn IP Enabled Services | Internet / business phone carrier | – |
| 661-474 | Verizon Wireless | Mobile carrier | 2010 |
| 661-534 | CenturyLink / Lumen | Local phone company | 2015 |
| 661-545 | T-Mobile (including Sprint) | Mobile carrier | 2020 |
| 661-553 | Bandwidth | Internet / business phone carrier | 2015 |
| 661-561 | Onvoy | Internet / business phone carrier | 2020 |
| 661-586 | AT&T Mobility | Mobile carrier | – |
| 661-642 | Teleport Communications America | Internet / business phone carrier | 2023 |
| 661-653 | T-Mobile (including Sprint) | Mobile carrier | 2022 |
| 661-690 | T-Mobile (including Sprint) | Mobile carrier | 2019 |
| 661-709 | T-Mobile (including Sprint) | Mobile carrier | 2001 |
| 661-720 | AT&T (local phone) | Local phone company | – |
| 661-721 | AT&T (local phone) | Local phone company | – |
| 661-725 | AT&T (local phone) | Local phone company | – |
| 661-732 | Fractel | Internet / business phone carrier | 2020 |
| 661-778 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 661-922 | Fractel | Internet / business phone carrier | 2021 |
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.