All assignees
709 prefixes in 520 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 520-501 | TUCSON | 506J | 2020-10-22 | Yes |
| 520-502 | SASABE | 630E | 2020-06-02 | Yes |
| 520-503 | WILLCOX | 630E | 2020-12-22 | Yes |
| 520-504 | SIERRAVIST | 6529 | 2021-04-02 | Yes |
| 520-505 | TUCSON | 7175 | 2009-07-20 | Yes |
| 520-506 | TOMBSTONE | 630E | 2020-12-23 | Yes |
| 520-507 | WILLCOX | 6572 | — | — |
| 520-508 | SIERRAVIST | 6572 | — | — |
| 520-509 | CASAGRANDE | 3285 | 2001-05-15 | Yes |
| 520-510 | CASAGRANDE | 6010 | — | Yes |
| 520-511 | XXXXXXXXXX | MULT | — | — |
| 520-512 | TUCSON | 9636 | — | Yes |
| 520-513 | TUCSON | 9636 | — | Yes |
| 520-514 | TUCSON | 9636 | — | — |
| 520-515 | SIERRAVIST | 9636 | — | — |
| 520-516 | TUCSON | 9636 | — | — |
| 520-517 | SACATON | 6572 | 2021-04-12 | Yes |
| 520-518 | CASAGRANDE | 6010 | — | Yes |
| 520-519 | TUCSON | 9636 | — | Yes |
| 520-520 | NOGALES | 630E | 2022-09-26 | Yes |
| 520-521 | SAN MANUEL | 321J | 2020-10-26 | Yes |
| 520-522 | CASABLANCA | 965H | 2020-06-02 | Yes |
| 520-523 | SIERRAVIST | 630E | 2020-05-07 | Yes |
| 520-524 | TUCSON | 630E | 2020-12-21 | Yes |
| 520-525 | BISBEE | 630E | 2020-05-07 | Yes |
| 520-526 | TUCSON | 939H | 2017-04-28 | Yes |
| 520-527 | BENSON | 630E | 2020-12-22 | Yes |
| 520-528 | TUCSON | 6572 | 2015-01-19 | Yes |
| 520-529 | TUCSON | 9636 | — | — |
| 520-530 | TUCSON | 630E | 2020-10-02 | Yes |
| 520-531 | TUCSON | 9636 | — | — |
| 520-532 | CASAGRANDE | 630E | 2020-12-23 | Yes |
| 520-533 | SIERRAVIST | 9636 | — | — |
| 520-534 | TUCSON | 6529 | 2021-01-11 | Yes |
| 520-535 | TUCSON | 6529 | 2020-12-08 | Yes |
| 520-536 | DOUGLAS | 630E | 2020-12-22 | Yes |
| 520-537 | TUCSON | 515J | 2021-03-04 | Yes |
| 520-538 | SIERRAVIST | 9636 | — | — |
| 520-539 | TUCSON | 6572 | 2014-04-09 | Yes |
| 520-540 | TUCSON | 587F | 2022-12-15 | Yes |
| 520-541 | WILLCOX | 6572 | 2021-07-07 | Yes |
| 520-542 | TUCSON | 3285 | 2021-08-04 | Yes |
| 520-543 | TUCSON | 6529 | 2021-05-14 | Yes |
| 520-544 | TUCSON | 9636 | — | — |
| 520-545 | TUCSON | 7552 | — | — |
| 520-546 | TUCSON | 9636 | — | — |
| 520-547 | TUCSON | 7552 | — | — |
| 520-548 | TUCSON | 6010 | 2001-07-19 | — |
| 520-549 | TUCSON | 6572 | — | Yes |
| 520-550 | KOMATKE | 2179 | — | — |
| 520-551 | TUCSON | 6010 | 2001-11-19 | — |
| 520-552 | BISBEE | 630E | — | Yes |
| 520-553 | CASAGRANDE | 6529 | 2021-07-19 | Yes |
| 520-554 | TUCSON | 6010 | 2021-08-09 | Yes |
| 520-555 | DIR ASST | MULT | — | — |
| 520-556 | SIERRAVIST | 6529 | 2021-08-24 | Yes |
| 520-557 | CASAGRANDE | 939H | 2022-11-04 | Yes |
| 520-558 | PORTAL | 2176 | — | — |
| 520-559 | SIERRAVIST | 6572 | — | — |
| 520-560 | CASAGRANDE | 6010 | — | — |
| 520-561 | TUCSON | 6572 | — | Yes |
| 520-562 | SACATON | 2179 | — | — |
| 520-563 | BENSON | 515J | 2021-09-03 | Yes |
| 520-564 | DOUGLAS | 515J | 2021-09-03 | Yes |
| 520-565 | TUCSON | 6010 | 2021-08-09 | Yes |
| 520-566 | TUCSON | 9636 | — | — |
| 520-567 | HAYDEN | 515J | 2021-09-03 | Yes |
| 520-568 | CASAGRANDE | 9636 | — | — |
| 520-569 | SAN MANUEL | 515J | 2021-09-03 | Yes |
| 520-570 | TUCSON | 9636 | — | Yes |
| 520-571 | TUCSON | 9636 | — | Yes |
| 520-572 | TUCSON | 9636 | — | — |
| 520-573 | TUCSON | 9636 | — | — |
| 520-574 | TUCSON | 9636 | — | — |
| 520-575 | TUCSON | 9636 | — | — |
| 520-576 | TUCSON | 9636 | — | Yes |
| 520-577 | TUCSON | 9636 | — | — |
| 520-578 | TUCSON | 9636 | — | — |
| 520-579 | TUCSON | 9636 | — | — |
| 520-580 | SUPERIOR | 624H | 2021-06-28 | Yes |
| 520-581 | TOMBSTONE | 515J | 2021-09-03 | Yes |
| 520-582 | CASAGRANDE | 7552 | — | Yes |
| 520-583 | WHITLOW | 515J | 2021-09-03 | Yes |
| 520-584 | TUCSON | 9636 | — | — |
| 520-585 | TUCSON | 5562 | 2016-03-09 | Yes |
| 520-586 | BENSON | 9636 | — | — |
| 520-587 | PORTAL | 6010 | 2021-09-24 | — |
| 520-588 | CASCABEL | 965H | 2020-09-24 | Yes |
| 520-589 | TUCSON | 3285 | 2015-07-29 | Yes |
| 520-590 | BISBEE | 6572 | 2021-11-10 | Yes |
| 520-591 | TUCSON | 6572 | — | — |
| 520-592 | NOGALES | 073H | 2021-10-04 | Yes |
| 520-593 | HAYDEN | 630E | 2020-12-24 | Yes |
| 520-594 | TUCSON | 700J | — | Yes |
| 520-595 | BENSON | 508J | 2015-06-05 | Yes |
| 520-596 | TUCSON | 6529 | 2021-10-26 | Yes |
| 520-597 | SUPERIOR | 630E | 2016-03-22 | Yes |
| 520-598 | CASAGRANDE | 5562 | 2021-10-11 | Yes |
| 520-599 | TUCSON | 6010 | 2014-12-15 | Yes |
| 520-600 | TUCSON | 630E | 2017-10-10 | Yes |
These are initial assignees from NANPA CO-code records — because of number portability, the current serving carrier of individual numbers may differ. Bulk export requires a membership.