All assignees
709 prefixes in 520 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 520-300 | TUCSON | 6572 | 2007-03-22 | Yes |
| 520-301 | TUCSON | 6010 | 2007-05-03 | Yes |
| 520-302 | TUCSON | 6010 | 2007-02-12 | Yes |
| 520-303 | TUCSON | 630E | 2008-01-02 | Yes |
| 520-304 | TUCSON | 6010 | — | — |
| 520-305 | TUCSON | 6572 | 2007-10-09 | Yes |
| 520-306 | TUCSON | 6572 | 2009-03-12 | Yes |
| 520-307 | TUCSON | 6572 | — | — |
| 520-308 | TUCSON | 6010 | 2009-09-09 | Yes |
| 520-309 | TUCSON | 6010 | 2005-09-30 | Yes |
| 520-310 | TUCSON | 6572 | 2009-09-09 | Yes |
| 520-311 | XXXXXXXXXX | MULT | — | — |
| 520-312 | TUCSON | 6010 | — | — |
| 520-313 | NOGALES | 6529 | 2001-05-15 | Yes |
| 520-314 | TUCSON | 3285 | 2011-02-09 | Yes |
| 520-315 | CASABLANCA | 2179 | — | — |
| 520-316 | CASAGRANDE | 9636 | — | — |
| 520-317 | HAYDEN | 630E | 2016-07-13 | Yes |
| 520-318 | TUCSON | 9636 | — | — |
| 520-319 | TUCSON | 9636 | — | — |
| 520-320 | TUCSON | 9636 | — | — |
| 520-321 | TUCSON | 9636 | — | — |
| 520-322 | TUCSON | 9636 | — | — |
| 520-323 | TUCSON | 9636 | — | — |
| 520-324 | TUCSON | 9636 | — | — |
| 520-325 | TUCSON | 9636 | — | — |
| 520-326 | TUCSON | 9636 | — | — |
| 520-327 | TUCSON | 9636 | — | — |
| 520-328 | TUCSON | 9636 | 2014-05-14 | Yes |
| 520-329 | TUCSON | 7217 | 2010-06-28 | Yes |
| 520-330 | TUCSON | 6572 | 2016-07-06 | Yes |
| 520-331 | TUCSON | 6529 | — | — |
| 520-332 | TUCSON | 6529 | 2012-05-17 | Yes |
| 520-333 | TUCSON | 7229 | 2010-12-17 | Yes |
| 520-334 | TUCSON | 6572 | 2008-10-02 | Yes |
| 520-335 | SIERRAVIST | 318J | — | Yes |
| 520-336 | TUCSON | 6010 | 2009-02-13 | Yes |
| 520-337 | WILLCOX | 3285 | 2008-05-05 | Yes |
| 520-338 | TUCSON | 630E | 2011-10-07 | Yes |
| 520-339 | TUCSON | 6010 | 2008-09-12 | Yes |
| 520-340 | CASAGRANDE | 6572 | 2016-09-01 | Yes |
| 520-341 | NOGALES | 073H | 2016-12-09 | Yes |
| 520-342 | TUCSON | 630E | 2007-03-08 | Yes |
| 520-343 | TUCSON | 6572 | 2007-05-23 | Yes |
| 520-344 | TUCSON | 6010 | 2007-04-24 | Yes |
| 520-345 | TUCSON | 6572 | 2013-01-11 | Yes |
| 520-346 | BISBEE | 579F | 2018-09-21 | Yes |
| 520-347 | TUCSON | 073H | — | Yes |
| 520-348 | WILLCOX | 508J | 2015-06-22 | Yes |
| 520-349 | TUCSON | 6572 | — | — |
| 520-350 | CASAGRANDE | 947E | 2008-05-14 | Yes |
| 520-351 | TUCSON | 7552 | 2005-10-11 | Yes |
| 520-352 | TUCSON | 7175 | — | Yes |
| 520-353 | BISBEE | 630E | 2012-05-08 | Yes |
| 520-354 | TUCSON | 6572 | 2016-10-27 | Yes |
| 520-355 | TUCSON | 587F | 2012-09-07 | Yes |
| 520-356 | HAYDEN | 9636 | — | Yes |
| 520-357 | HAYDEN | 9636 | — | Yes |
| 520-358 | TUCSON | 6010 | 2001-03-06 | — |
| 520-359 | TUCSON | 5562 | 2014-06-24 | Yes |
| 520-360 | TUCSON | 6010 | — | — |
| 520-361 | SANTA ROSA | 2173 | — | — |
| 520-362 | W SANSIMON | 2173 | — | — |
| 520-363 | HAYDEN | 9636 | — | Yes |
| 520-364 | DOUGLAS | 9636 | — | — |
| 520-365 | TUCSON | 6529 | 2012-04-24 | Yes |
| 520-366 | BISBEE | 9636 | — | Yes |
| 520-367 | TUCSON | 624H | 2017-07-13 | Yes |
| 520-368 | DOUGLAS | 9636 | 2007-11-07 | Yes |
| 520-369 | TUCSON | 3285 | 2011-09-28 | Yes |
| 520-370 | TUCSON | 6529 | — | Yes |
| 520-371 | CASAGRANDE | 5562 | — | Yes |
| 520-372 | TUCSON | 318J | 2019-08-05 | Yes |
| 520-373 | TUCSON | 6529 | 2012-10-31 | Yes |
| 520-374 | CASAGRANDE | 9636 | — | — |
| 520-375 | NOGALES | 9636 | — | Yes |
| 520-376 | SIERRAVIST | 5562 | 2019-02-19 | Yes |
| 520-377 | NOGALES | 9636 | — | — |
| 520-378 | SIERRAVIST | 9636 | — | — |
| 520-379 | DOUGLAS | 630E | — | Yes |
| 520-380 | CASAGRANDE | 6529 | 2019-08-23 | Yes |
| 520-381 | CASAGRANDE | 7175 | — | Yes |
| 520-382 | TUCSON | 7552 | — | Yes |
| 520-383 | SELLS | 2173 | — | — |
| 520-384 | WILLCOX | 9636 | — | — |
| 520-385 | SAN MANUEL | 9636 | — | Yes |
| 520-386 | BENSON | 6010 | 2019-12-11 | Yes |
| 520-387 | AJO | 3334 | — | — |
| 520-388 | TUCSON | 9636 | — | Yes |
| 520-389 | TUCSON | 6010 | 2014-10-09 | Yes |
| 520-390 | TUCSON | 6529 | — | Yes |
| 520-391 | SUPERIOR | 7175 | — | Yes |
| 520-392 | TUCSON | 6010 | 2009-12-29 | Yes |
| 520-393 | TUCSON | 9636 | — | Yes |
| 520-394 | NOGALES | 9636 | — | Yes |
| 520-395 | TUCSON | 318J | 2007-05-21 | Yes |
| 520-396 | TUCSON | 6572 | 2006-08-24 | Yes |
| 520-397 | NOGALES | 9636 | — | Yes |
| 520-398 | TUCSON | 9636 | — | Yes |
| 520-399 | TUCSON | 9636 | — | 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.