Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records
HAYWARD prefixes in area code 510
NANPA records 117 assigned NXX blocks to rate center HAYWARD in area code 510, 14.9% of the 785 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 20 holders hold those blocks, the largest being PACIFIC BELL (36), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA (14), NEW CINGULAR WIRELESS PCS, LLC (13). The earliest assignment on record here is 2001-03-22 and the most recent 2026-02-25. 84 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots. The same rate center name also appears in area codes 341, 715 – overlay codes cover the same geography, so a rate center is served by all of them.
117 assigned blocks – 14.9% of 510
20 holders of record
84 of them pooled in 1,000-number lots
Prefixes assigned here
| Prefix | Holder of record | Assigned | Pooled | In service |
|---|---|---|---|---|
| 510-200 | T-Mobile METROPCS, INC. | 2008-11-12 | yes | yes |
| 510-209 | T-Mobile METROPCS, INC. | – | yes | yes |
| 510-244 | Bandwidth BANDWIDTH.COM CLEC, LLC - CA | 2011-07-25 | yes | yes |
| 510-246 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2011-08-09 | yes | yes |
| 510-247 | AT&T PACIFIC BELL | – | yes | yes |
| 510-258 | AT&T PACIFIC BELL | – | yes | yes |
| 510-259 | AT&T PACIFIC BELL | – | yes | yes |
| 510-264 | AT&T PACIFIC BELL | – | yes | yes |
| 510-265 | AT&T PACIFIC BELL | – | yes | yes |
| 510-266 | AT&T PACIFIC BELL | – | yes | yes |
| 510-274 | UTILITY TELECOM GROUP, LLC - CA | – | yes | yes |
| 510-276 | AT&T PACIFIC BELL | – | no | yes |
| 510-278 | AT&T PACIFIC BELL | – | no | yes |
| 510-293 | AT&T PACIFIC BELL | – | yes | yes |
| 510-294 | T-Mobile METROPCS, INC. | 2011-11-04 | yes | yes |
| 510-300 | TPx U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | – | yes | yes |
| 510-303 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | no | yes |
| 510-305 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | no | yes |
| 510-310 | SEQUOIA WIRELESS, LLC | 2026-02-25 | yes | yes |
| 510-314 | T-Mobile T-MOBILE USA, INC. | 2007-07-02 | yes | yes |
| 510-315 | Lumen LEVEL 3 COMMUNICATIONS, LLC - CA | – | no | yes |
| 510-317 | AT&T PACIFIC BELL | – | no | yes |
| 510-329 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | no | yes |
| 510-330 | Onvoy ONVOY, LLC - CA | 2015-12-28 | yes | yes |
| 510-331 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | no | yes |
| 510-340 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2012-05-04 | yes | yes |
| 510-342 | TPx U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | – | yes | yes |
| 510-359 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2012-08-17 | yes | yes |
| 510-361 | Lumen LEVEL 3 TELECOM OF CALIFORNIA, LP - CA | 2014-10-27 | yes | yes |
| 510-362 | T-Mobile T-MOBILE USA, INC. | 2013-05-16 | yes | yes |
| 510-363 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2008-01-14 | yes | yes |
| 510-370 | Peerless PEERLESS NETWORK OF CALIFORNIA, LLC - CA | 2012-04-13 | yes | yes |
| 510-372 | Onvoy ONVOY, LLC - CA | – | yes | yes |
| 510-397 | Comcast COMCAST PHONE OF CALIFORNIA, LLC | 2008-08-28 | yes | yes |
| 510-398 | Bandwidth BANDWIDTH.COM CLEC, LLC - CA | 2012-08-17 | yes | yes |
| 510-415 | T-Mobile T-MOBILE USA, INC. | 2001-09-19 | no | yes |
| 510-427 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | – | no | yes |
| 510-432 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2001-11-28 | no | yes |
| 510-460 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2010-02-09 | yes | yes |
| 510-461 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2002-08-21 | yes | yes |
| 510-470 | Bandwidth BANDWIDTH.COM CLEC, LLC - CA | 2010-02-22 | yes | yes |
| 510-481 | AT&T PACIFIC BELL | – | no | yes |
| 510-512 | T-Mobile T-MOBILE USA, INC. | – | yes | yes |
| 510-514 | Peerless PEERLESS NETWORK OF CALIFORNIA, LLC - CA | 2016-09-19 | yes | yes |
| 510-537 | AT&T PACIFIC BELL | – | no | yes |
| 510-538 | AT&T PACIFIC BELL | – | no | yes |
| 510-546 | Charter ONVOY SPECTRUM, LLC | 2024-01-04 | yes | yes |
| 510-554 | 33 WIRELESS INC. | – | no | yes |
| 510-566 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | – | yes | yes |
| 510-571 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2017-08-16 | yes | yes |
| 510-576 | Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC | – | yes | yes |
| 510-581 | AT&T PACIFIC BELL | – | no | yes |
| 510-582 | AT&T PACIFIC BELL | – | no | yes |
| 510-583 | AT&T PACIFIC BELL | – | no | yes |
| 510-584 | Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC | – | yes | yes |
| 510-586 | Comcast COMCAST PHONE OF CALIFORNIA, LLC | – | yes | yes |
| 510-589 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | no | yes |
| 510-600 | Onvoy ONVOY, LLC - CA | – | yes | yes |
| 510-605 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2018-01-17 | yes | yes |
| 510-606 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2010-08-10 | yes | yes |
| 510-634 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2014-09-24 | yes | yes |
| 510-670 | AT&T PACIFIC BELL | – | no | yes |
| 510-674 | Onvoy ONVOY, LLC - CA | 2014-11-03 | yes | yes |
| 510-677 | T-Mobile METROPCS, INC. | 2001-03-22 | yes | yes |
| 510-688 | T-Mobile T-MOBILE USA, INC. | – | yes | yes |
| 510-690 | AT&T PACIFIC BELL | – | yes | yes |
| 510-695 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2007-08-17 | yes | yes |
| 510-706 | T-Mobile METROPCS, INC. | 2001-08-22 | no | yes |
| 510-723 | AT&T PACIFIC BELL | – | yes | yes |
| 510-727 | AT&T PACIFIC BELL | – | yes | yes |
| 510-728 | AT&T PACIFIC BELL | – | no | yes |
| 510-731 | Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | – | yes | yes |
| 510-732 | AT&T PACIFIC BELL | – | yes | yes |
| 510-733 | AT&T PACIFIC BELL | – | no | yes |
| 510-736 | T-Mobile T-MOBILE USA, INC. | 2013-12-09 | yes | yes |
| 510-750 | T-Mobile METROPCS, INC. | – | yes | yes |
| 510-751 | Onvoy ONVOY, LLC - CA | – | yes | yes |
| 510-754 | T-Mobile METROPCS, INC. | 2002-05-17 | yes | yes |
| 510-755 | T-Mobile METROPCS, INC. | – | yes | yes |
| 510-760 | T-Mobile METROPCS, INC. | – | yes | yes |
| 510-780 | AT&T PACIFIC BELL | – | yes | yes |
| 510-781 | AT&T PACIFIC BELL | – | yes | yes |
| 510-782 | AT&T PACIFIC BELL | – | no | yes |
| 510-783 | AT&T PACIFIC BELL | – | no | yes |
| 510-784 | AT&T PACIFIC BELL | – | no | yes |
| 510-785 | AT&T PACIFIC BELL | – | no | yes |
| 510-786 | AT&T PACIFIC BELL | – | yes | yes |
| 510-807 | T-Mobile T-MOBILE USA, INC. | 2019-05-28 | yes | yes |
| 510-819 | Charter ONVOY SPECTRUM, LLC | 2024-06-12 | yes | yes |
| 510-825 | T-Mobile METROPCS, INC. | 2001-10-18 | yes | yes |
| 510-826 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2016-12-09 | yes | yes |
| 510-828 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2001-03-22 | yes | yes |
| 510-856 | Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC | – | yes | yes |
| 510-861 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | yes | yes |
| 510-862 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | yes | yes |
| 510-876 | AT&T AT&T ENTERPRISES, LLC | 2014-03-27 | yes | yes |
| 510-880 | Onvoy ONVOY, LLC - CA | – | yes | yes |
| 510-881 | AT&T PACIFIC BELL | – | yes | yes |
| 510-884 | UTILITY TELECOM GROUP, LLC - CA | – | no | yes |
| 510-885 | AT&T PACIFIC BELL | – | no | yes |
| 510-886 | AT&T PACIFIC BELL | – | no | yes |
| 510-887 | AT&T PACIFIC BELL | – | no | yes |
| 510-888 | AT&T PACIFIC BELL | – | no | yes |
| 510-889 | AT&T PACIFIC BELL | – | yes | yes |
| 510-892 | Onvoy ONVOY, LLC - CA | – | yes | yes |
| 510-901 | Bandwidth BANDWIDTH.COM CLEC, LLC - CA | 2016-07-29 | yes | yes |
| 510-909 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | – | no | yes |
| 510-921 | AT&T TELEPORT COMMUNICATIONS AMERICA, LLC - CA | – | yes | yes |
| 510-925 | Bandwidth BANDWIDTH.COM CLEC, LLC - CA | 2014-09-18 | yes | yes |
| 510-931 | Lumen LEVEL 3 COMMUNICATIONS, LLC - CA | – | yes | yes |
| 510-935 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2014-03-27 | yes | yes |
| 510-940 | TPx U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | – | yes | yes |
| 510-951 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 2021-08-05 | yes | yes |
| 510-954 | Onvoy ONVOY, LLC - CA | 2018-12-03 | yes | yes |
| 510-962 | Lumen LEVEL 3 COMMUNICATIONS, LLC - CA | – | yes | yes |
| 510-963 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2015-11-13 | yes | yes |
| 510-999 | Onvoy ONVOY, LLC - CA | – | yes | yes |
The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.
Who holds the blocks
| Holder | Brand | Blocks | Share here |
|---|---|---|---|
| PACIFIC BELL | AT&T | 36 | 30.8% |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | Verizon | 14 | 12% |
| NEW CINGULAR WIRELESS PCS, LLC | AT&T | 13 | 11.1% |
| METROPCS, INC. | T-Mobile | 10 | 8.5% |
| ONVOY, LLC - CA | Onvoy | 9 | 7.7% |
| T-MOBILE USA, INC. | T-Mobile | 7 | 6% |
| BANDWIDTH.COM CLEC, LLC - CA | Bandwidth | 5 | 4.3% |
| U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | TPx | 3 | 2.6% |
| LEVEL 3 COMMUNICATIONS, LLC - CA | Lumen | 3 | 2.6% |
| MCIMETRO ACCESS TRANSMISSION SERVICES LLC | Verizon | 3 | 2.6% |
| UTILITY TELECOM GROUP, LLC - CA | – | 2 | 1.7% |
| PEERLESS NETWORK OF CALIFORNIA, LLC - CA | Peerless | 2 | 1.7% |
| COMCAST PHONE OF CALIFORNIA, LLC | Comcast | 2 | 1.7% |
| ONVOY SPECTRUM, LLC | Charter | 2 | 1.7% |
| SEQUOIA WIRELESS, LLC | – | 1 | 0.9% |
| LEVEL 3 TELECOM OF CALIFORNIA, LP - CA | Lumen | 1 | 0.9% |
| 33 WIRELESS INC. | – | 1 | 0.9% |
| MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | Verizon | 1 | 0.9% |
| AT&T ENTERPRISES, LLC | AT&T | 1 | 0.9% |
| TELEPORT COMMUNICATIONS AMERICA, LLC - CA | AT&T | 1 | 0.9% |
Same rate center in other codes
Overlay codes cover the same geography, so one rate center is served by all of them.
Frequently asked
Which prefixes belong to HAYWARD in area code 510?
117 blocks: 200, 209, 244, 246, 247, 258, 259, 264, 265, 266, 274, 276 and 105 more, all listed in the table above.
Which carriers have numbers in HAYWARD?
PACIFIC BELL (36 blocks), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA (14 blocks), NEW CINGULAR WIRELESS PCS, LLC (13 blocks), METROPCS, INC. (10 blocks), ONVOY, LLC - CA (9 blocks), T-MOBILE USA, INC. (7 blocks). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.
Is HAYWARD a city?
It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.