All assignees
709 prefixes in 520 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 520-982 | TUCSON | 6529 | — | Yes |
| 520-987 | NOGALES | 6572 | — | Yes |
| 520-988 | NOGALES | 6572 | — | Yes |
| 520-989 | TUCSON | 7175 | — | Yes |
| 520-990 | TUCSON | 6529 | — | Yes |
| 520-991 | TUCSON | 6529 | — | Yes |
| 520-993 | SELLS | 6572 | — | Yes |
| 520-994 | SASABE | 516J | 2022-02-18 | Yes |
| 520-999 | TUCSON | 630E | 2012-11-05 | 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.