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Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

Area code 510 prefixes

785 of the 786 possible NXX blocks are assigned in area code 510 (99.9% of capacity), spread across 13 rate centers and 32 holders. The largest holders are PACIFIC BELL (277 blocks, 35.3%), NEW CINGULAR WIRELESS PCS, LLC (78 blocks, 9.9%), T-MOBILE USA, INC. (65 blocks, 8.3%). Grouped by brand, AT&T accounts for 377 blocks; brand-attributable holders cover 97% of the code, and the rest are CLECs, VoIP wholesalers and regional carriers that trade under their own names. The assignment records here run from 2001-01-25 to 2026-02-25, with 26 blocks handed out in 2001 alone. 514 blocks (65%) are in thousands-block pooling, meaning the block is shared between carriers in 1,000-number lots rather than held whole – which is why a single NXX can serve several carriers at once. 154 were growth assignments – additional blocks to a carrier that had already filled its earlier ones.

785 assigned blocks of 786
13 rate centers
32 holders of record
65% in thousands-block pooling

Largest holders in 510

Holder of record, as NANPA names itBrandBlocksShare
PACIFIC BELL AT&T 277 35.3%
NEW CINGULAR WIRELESS PCS, LLC AT&T 78 9.9%
T-MOBILE USA, INC. T-Mobile 65 8.3%
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA Verizon 60 7.6%
METROPCS, INC. T-Mobile 45 5.7%
MCIMETRO ACCESS TRANSMISSION SERVICES LLC Verizon 37 4.7%
ONVOY, LLC - CA Onvoy 37 4.7%
LEVEL 3 COMMUNICATIONS, LLC - CA Lumen 34 4.3%
BANDWIDTH.COM CLEC, LLC - CA Bandwidth 29 3.7%
TELEPORT COMMUNICATIONS AMERICA, LLC - CA AT&T 19 2.4%
U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS TPx 18 2.3%
COMCAST PHONE OF CALIFORNIA, LLC Comcast 12 1.5%

Names are printed as they appear in the assignment records, which is the legal entity rather than the brand. Holding a block is not the same as serving the numbers in it: portability moves numbers between carriers and pooling splits a block between several.

Rate centers with their own page

Rate centers where at least three blocks are assigned, excluding the numbered metro zone codes. The remainder are in the full table below.

OKLD MN-PD 204HAYWARD 117FRNK MAIN 81OKLD BKLY 70OKLD TRNID 60RICHMOND 53FRNK OLIVR 45OKLD ALMD 42OKLD FRTVL 39ELSBR-PINL 28FRNK GRNLF 25HRCUL-RODE 14CROCKETT 7

All 785 assigned blocks

One row per NXX. “Pooled” means carriers draw 1,000-number lots from the block rather than holding all 10,000, so a pooled prefix can belong to several carriers at once. “Not in service” means assigned but not yet open for calls – a caller ID from one of those is necessarily spoofed. The holder column gives the brand where the legal entity maps to one; the full legal names are in the holders table above, exactly as NANPA records them.

PrefixHolder of recordRate centerAssignedPooledIn service
510-200 T-Mobile HAYWARD 2008-11-12 yes yes
510-201 Peerless OKLD MN-PD 2009-02-14 yes yes
510-202 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – – yes
510-203 T-Mobile FRNK MAIN 2015-09-22 yes yes
510-204 AT&T OKLD BKLY – – yes
510-205 T-Mobile OKLD ALMD – yes yes
510-206 AT&T OKLD MN-PD – – yes
510-207 AT&T OKLD MN-PD – – yes
510-208 AT&T OKLD MN-PD – – yes
510-209 T-Mobile HAYWARD – yes yes
510-210 Bandwidth RICHMOND 2013-01-04 yes yes
510-212 Spok FRNK OLIVR – – yes
510-213 T-Mobile OKLD FRTVL 2002-09-19 yes yes
510-214 Verizon OKLD ALMD – yes yes
510-215 AT&T RICHMOND – – yes
510-216 T-Mobile OKLD FRTVL 2019-09-27 yes yes
510-217 AT&T OKLD ALMD – yes yes
510-218 Spok FRNK OLIVR – – yes
510-219 AT&T OKLD MN-PD – – yes
510-220 AT&T OKLD MN-PD – – yes
510-221 T-Mobile RICHMOND 2007-02-08 yes yes
510-222 AT&T ELSBR-PINL – – yes
510-223 AT&T ELSBR-PINL – – yes
510-224 T-Mobile HRCUL-RODE 2001-10-18 yes yes
510-225 Verizon OKLD BKLY – yes yes
510-226 AT&T FRNK OLIVR – – yes
510-227 Lumen OKLD ALMD – yes yes
510-228 Lumen OKLD FRTVL – yes yes
510-229 AT&T OKLD BKLY – yes yes
510-230 T-Mobile RICHMOND 2007-02-15 yes yes
510-231 AT&T RICHMOND – – yes
510-232 AT&T RICHMOND – – yes
510-233 AT&T RICHMOND – – yes
510-234 AT&T RICHMOND – – yes
510-235 AT&T RICHMOND – – yes
510-236 AT&T RICHMOND – – yes
510-237 AT&T RICHMOND – – yes
510-238 AT&T OKLD MN-PD – – yes
510-239 TPx OKLD ALMD – yes yes
510-240 Lumen FRNK GRNLF – yes yes
510-241 T-Mobile ELSBR-PINL 2015-09-22 yes yes
510-242 AT&T RICHMOND – – yes
510-243 AT&T ELSBR-PINL – yes yes
510-244 Bandwidth HAYWARD 2011-07-25 yes yes
510-245 AT&T HRCUL-RODE – – yes
510-246 Verizon HAYWARD 2011-08-09 yes yes
510-247 AT&T HAYWARD – yes yes
510-248 Lumen FRNK MAIN – yes yes
510-249 AT&T FRNK OLIVR – – yes
510-250 Lumen OKLD MN-PD – yes yes
510-251 AT&T OKLD MN-PD – – yes
510-252 AT&T FRNK OLIVR – – yes
510-253 Lumen RICHMOND – yes yes
510-254 Lumen OKLD ALMD 2011-09-15 yes yes
510-255 Bandwidth RICHMOND 2011-04-28 yes yes
510-256 Bandwidth CROCKETT – yes yes
510-257 AT&T FRNK OLIVR – yes yes
510-258 AT&T HAYWARD – yes yes
510-259 AT&T HAYWARD – yes yes
510-260 Comcast RICHMOND – yes yes
510-261 AT&T OKLD FRTVL – – yes
510-262 AT&T ELSBR-PINL – yes yes
510-263 AT&T OKLD ALMD – yes yes
510-264 AT&T HAYWARD – yes yes
510-265 AT&T HAYWARD – yes yes
510-266 AT&T HAYWARD – yes yes
510-267 AT&T OKLD MN-PD – – yes
510-268 AT&T OKLD MN-PD – yes yes
510-269 Verizon OKLD FRTVL – yes yes
510-270 Verizon FRNK OLIVR – yes yes
510-271 AT&T OKLD MN-PD – – yes
510-272 AT&T OKLD MN-PD – yes yes
510-273 AT&T OKLD MN-PD – – yes
510-274 UTILITY TELECOM GROUP, LLC - CA HAYWARD – yes yes
510-275 Onvoy ELSBR-PINL – yes yes
510-276 AT&T HAYWARD – – yes
510-277 Lumen OKLD BKLY – yes yes
510-278 AT&T HAYWARD – – yes
510-279 Lumen FRNK OLIVR – yes yes
510-280 Verizon OKLD BKLY – yes yes
510-281 Onvoy OKLD MN-PD – – yes
510-282 T-Mobile OKLD MN-PD 2001-12-26 – yes
510-283 Verizon ELSBR-PINL – yes yes
510-284 AT&T FRNK MAIN – yes yes
510-285 Verizon OKLD MN-PD – yes yes
510-286 AT&T OKLD MN-PD – – yes
510-287 AT&T OKLD MN-PD – yes yes
510-288 Onvoy OKLD MN-PD – – yes
510-289 AT&T OKLD MN-PD – – yes
510-290 T-Mobile OKLD MN-PD – yes yes
510-291 Onvoy OKLD MN-PD – yes yes
510-292 AT&T OKLD BKLY – yes yes
510-293 AT&T HAYWARD – yes yes
510-294 T-Mobile HAYWARD 2011-11-04 yes yes
510-295 Verizon OKLD BKLY – yes yes
510-296 Lumen HRCUL-RODE – yes yes
510-297 AT&T OKLD TRNID – – yes
510-298 AT&T FRNK MAIN 2012-12-07 yes yes
510-299 Verizon FRNK MAIN – – yes
510-300 TPx HAYWARD – yes yes
510-301 Verizon OKLD MN-PD – – yes
510-302 AT&T OKLD MN-PD – yes yes
510-303 AT&T HAYWARD – – yes
510-304 AT&T FRNK MAIN – – yes
510-305 AT&T HAYWARD – – yes
510-306 T-Mobile OKLD ALMD – yes yes
510-307 AT&T RICHMOND – yes yes
510-308 Spok OKLD MN-PD – – yes
510-309 T-Mobile ELSBR-PINL 2014-10-24 yes yes
510-310 SEQUOIA WIRELESS, LLC HAYWARD 2026-02-25 yes yes
510-312 COMMIO, LLC CROCKETT 2023-08-09 yes yes
510-313 AT&T HRCUL-RODE – yes yes
510-314 T-Mobile HAYWARD 2007-07-02 yes yes
510-315 Lumen HAYWARD – – yes
510-316 AT&T OKLD MN-PD – yes yes
510-317 AT&T HAYWARD – – yes
510-318 Verizon OKLD MN-PD – yes yes
510-319 Onvoy FRNK OLIVR 2015-12-01 yes yes
510-320 AT&T FRNK MAIN 2013-09-12 yes yes
510-321 Spok OKLD MN-PD – – yes
510-322 Verizon HRCUL-RODE – yes yes
510-323 Verizon RICHMOND – yes yes
510-324 AT&T FRNK GRNLF – yes yes
510-325 AT&T OKLD MN-PD – – yes
510-326 AT&T OKLD MN-PD – – yes
510-327 Onvoy HRCUL-RODE – yes yes
510-328 T-Mobile OKLD FRTVL 2013-01-31 yes yes
510-329 AT&T HAYWARD – – yes
510-330 Onvoy HAYWARD 2015-12-28 yes yes
510-331 AT&T HAYWARD – – yes
510-332 AT&T OKLD MN-PD – – yes
510-333 AT&T OKLD MN-PD – – yes
510-334 AT&T RICHMOND – – yes
510-335 Onvoy FRNK MAIN – yes yes
510-336 AT&T OKLD FRTVL – yes yes
510-337 AT&T OKLD ALMD – yes yes
510-338 AT&T OKLD MN-PD – yes yes
510-339 AT&T OKLD MN-PD – – yes
510-340 Verizon HAYWARD 2012-05-04 yes yes
510-342 TPx HAYWARD – yes yes
510-343 TPx OKLD TRNID – yes yes
510-344 Lumen FRNK OLIVR – yes yes
510-345 T-Mobile OKLD BKLY 2016-01-15 yes yes
510-346 AT&T OKLD TRNID – yes yes
510-347 AT&T OKLD TRNID – yes yes
510-348 33 WIRELESS INC. OKLD MN-PD – – yes
510-349 American Messaging RICHMOND – – yes
510-350 AT&T OKLD MN-PD – yes yes
510-351 AT&T OKLD TRNID – – yes
510-352 AT&T OKLD TRNID – – yes
510-353 AT&T FRNK OLIVR – yes yes
510-354 AT&T FRNK OLIVR – – yes
510-355 Lumen OKLD ALMD – yes yes
510-356 AT&T OKLD BKLY 2007-11-28 yes yes
510-357 AT&T OKLD TRNID – – yes
510-358 AT&T FRNK MAIN 2011-07-08 yes yes
510-359 Verizon HAYWARD 2012-08-17 yes yes
510-360 AT&T FRNK OLIVR – – yes
510-361 Lumen HAYWARD 2014-10-27 yes yes
510-362 T-Mobile HAYWARD 2013-05-16 yes yes
510-363 Verizon HAYWARD 2008-01-14 yes yes
510-364 AT&T FRNK MAIN 2001-11-28 – yes
510-365 T-Mobile OKLD BKLY 2013-09-26 yes yes
510-366 AT&T FRNK MAIN – – yes
510-367 AT&T RICHMOND – – yes
510-368 Verizon OKLD MN-PD – yes yes
510-369 Onvoy RICHMOND 2016-02-04 yes yes
510-370 Peerless HAYWARD 2012-04-13 yes yes
510-371 Lumen FRNK MAIN 2008-08-07 yes yes
510-372 Onvoy HAYWARD – yes yes
510-373 Onvoy OKLD ALMD – yes yes
510-374 AT&T RICHMOND – yes yes
510-375 T-Mobile RICHMOND 2001-12-26 yes yes
510-376 T-Mobile FRNK MAIN – yes yes
510-377 T-Mobile FRNK MAIN – yes yes
510-378 AT&T FRNK MAIN – – yes
510-379 Lumen OKLD MN-PD – yes yes
510-380 Onvoy OKLD MN-PD – yes yes
510-381 Verizon OKLD MN-PD – – yes
510-382 AT&T OKLD TRNID – – yes
510-383 AT&T OKLD TRNID – yes yes
510-384 AT&T OKLD MN-PD – – yes
510-385 T-Mobile OKLD MN-PD – yes yes
510-386 AT&T FRNK MAIN – – yes
510-387 AT&T OKLD MN-PD – – yes
510-388 AT&T OKLD MN-PD – – yes
510-389 AT&T OKLD TRNID 2023-06-28 yes yes
510-390 Verizon OKLD MN-PD – yes yes
510-391 AT&T FRNK MAIN 2023-12-21 yes yes
510-392 AT&T ELSBR-PINL 2024-01-16 yes yes
510-393 T-Mobile OKLD MN-PD – yes yes
510-394 AT&T OKLD TRNID – yes yes
510-395 AT&T OKLD FRTVL – yes yes
510-396 T-Mobile FRNK MAIN 2001-12-26 – yes
510-397 Comcast HAYWARD 2008-08-28 yes yes
510-398 Bandwidth HAYWARD 2012-08-17 yes yes
510-399 Onvoy FRNK MAIN 2016-05-06 yes yes
510-400 Verizon FRNK GRNLF – yes yes
510-401 TPx FRNK GRNLF – yes yes
510-402 Bandwidth FRNK MAIN – yes yes
510-403 TPx FRNK OLIVR – yes yes
510-404 Verizon FRNK GRNLF – yes yes
510-405 Onvoy FRNK MAIN – – yes
510-406 Verizon OKLD MN-PD – yes yes
510-407 Verizon OKLD MN-PD – – yes
510-408 AT&T ELSBR-PINL 2009-11-25 yes yes
510-409 AT&T OKLD MN-PD – – yes
510-410 Verizon OKLD MN-PD – – yes
510-412 AT&T RICHMOND – – yes
510-413 AT&T FRNK OLIVR – yes yes
510-414 Verizon OKLD MN-PD – – yes
510-415 T-Mobile HAYWARD 2001-09-19 – yes
510-416 NORTH COUNTY COMMUNICATION CORPORATION - CA OKLD BKLY – – yes
510-417 T-Mobile ELSBR-PINL 2002-09-19 yes yes
510-418 Verizon OKLD MN-PD – – yes
510-419 AT&T OKLD MN-PD – yes yes
510-420 AT&T OKLD MN-PD – – yes
510-421 Verizon OKLD MN-PD – – yes
510-422 T-Mobile OKLD FRTVL 2015-09-25 yes yes
510-423 Windstream OKLD BKLY 2008-11-07 yes yes
510-424 T-Mobile OKLD FRTVL 2016-07-29 yes yes
510-425 AT&T OKLD TRNID – yes yes
510-426 Verizon RICHMOND 2014-03-27 yes yes
510-427 Verizon HAYWARD – – yes
510-428 AT&T OKLD MN-PD – – yes
510-429 AT&T FRNK GRNLF – – yes
510-430 AT&T OKLD TRNID – – yes
510-431 Lumen FRNK GRNLF – yes yes
510-432 AT&T HAYWARD 2001-11-28 – yes
510-433 AT&T OKLD MN-PD – yes yes
510-434 AT&T OKLD FRTVL – yes yes
510-435 T-Mobile OKLD MN-PD – yes yes
510-436 AT&T OKLD FRTVL – – yes
510-437 AT&T OKLD FRTVL – yes yes
510-438 AT&T FRNK OLIVR – yes yes
510-439 Onvoy RICHMOND – yes yes
510-440 AT&T FRNK OLIVR – yes yes
510-441 AT&T FRNK GRNLF – yes yes
510-442 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – – yes
510-443 Peerless FRNK MAIN 2009-02-14 yes yes
510-444 AT&T OKLD MN-PD – yes yes
510-445 AT&T FRNK OLIVR – yes yes
510-446 AT&T OKLD MN-PD – yes yes
510-447 T-Mobile RICHMOND 2011-12-09 yes yes
510-448 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – – yes
510-449 AT&T FRNK MAIN – yes yes
510-450 AT&T OKLD MN-PD – – yes
510-451 AT&T OKLD MN-PD – – yes
510-452 AT&T OKLD MN-PD – yes yes
510-453 T-Mobile FRNK MAIN – yes yes
510-454 AT&T OKLD TRNID 2012-11-30 yes yes
510-455 T-Mobile CROCKETT 2001-04-20 yes yes
510-456 TPx FRNK MAIN – yes yes
510-457 AT&T OKLD MN-PD – yes yes
510-458 Verizon FRNK MAIN 2014-10-14 yes yes
510-459 T-Mobile OKLD MN-PD – yes yes
510-460 Verizon HAYWARD 2010-02-09 yes yes
510-461 AT&T HAYWARD 2002-08-21 yes yes
510-462 Onvoy FRNK GRNLF 2016-05-04 yes yes
510-463 TPx OKLD MN-PD – yes yes
510-464 AT&T OKLD MN-PD – yes yes
510-465 AT&T OKLD MN-PD – – yes
510-466 AT&T OKLD MN-PD – yes yes
510-467 Lumen OKLD FRTVL – yes yes
510-468 Verizon FRNK MAIN – – yes
510-469 T-Mobile OKLD MN-PD – yes yes
510-470 Bandwidth HAYWARD 2010-02-22 yes yes
510-471 AT&T FRNK GRNLF – – yes
510-472 T-Mobile OKLD MN-PD 2001-08-22 – yes
510-473 Verizon OKLD ALMD – yes yes
510-474 Verizon FRNK GRNLF – yes yes
510-475 AT&T FRNK GRNLF – – yes
510-476 AT&T FRNK GRNLF – yes yes
510-477 AT&T FRNK GRNLF – – yes
510-478 Verizon RICHMOND – yes yes
510-479 AT&T OKLD FRTVL – yes yes
510-480 T-Mobile ELSBR-PINL 2013-09-26 yes yes
510-481 AT&T HAYWARD – – yes
510-482 AT&T OKLD FRTVL – – yes
510-483 AT&T OKLD TRNID – – yes
510-484 T-Mobile OKLD MN-PD – yes yes
510-485 T-Mobile OKLD FRTVL – yes yes
510-486 AT&T OKLD BKLY – – yes
510-487 AT&T FRNK GRNLF – – yes
510-488 Verizon OKLD FRTVL – yes yes
510-489 AT&T FRNK GRNLF – – yes
510-490 AT&T FRNK OLIVR – – yes
510-491 AT&T FRNK GRNLF – yes yes
510-492 AT&T FRNK OLIVR – yes yes
510-493 Verizon FRNK MAIN – yes yes
510-494 AT&T FRNK MAIN – – yes
510-495 AT&T OKLD BKLY – yes yes
510-496 TPx OKLD MN-PD – yes yes
510-497 Verizon FRNK OLIVR – yes yes
510-498 AT&T FRNK OLIVR – yes yes
510-499 AT&T OKLD MN-PD – – yes
510-500 Verizon OKLD FRTVL – yes yes
510-501 AT&T OKLD MN-PD – – yes
510-502 AT&T OKLD MN-PD – – yes
510-503 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – – yes
510-504 Verizon OKLD MN-PD – – yes
510-505 AT&T FRNK MAIN – yes yes
510-506 Verizon OKLD MN-PD – yes yes
510-507 Verizon OKLD MN-PD – yes yes
510-508 AT&T OKLD MN-PD – – yes
510-509 Lumen FRNK MAIN 2010-07-06 yes yes
510-510 SHELCOMM FRNK MAIN 2024-09-12 – yes
510-512 T-Mobile HAYWARD – yes yes
510-513 T-Mobile FRNK MAIN 2016-08-30 yes yes
510-514 Peerless HAYWARD 2016-09-19 yes yes
510-515 Spok OKLD MN-PD – – yes
510-516 Bandwidth FRNK MAIN 2010-09-03 yes yes
510-517 AT&T OKLD MN-PD – – yes
510-518 Peerless FRNK MAIN – yes yes
510-519 Verizon OKLD ALMD 2017-08-07 yes yes
510-520 AT&T OKLD MN-PD – – yes
510-521 AT&T OKLD ALMD – – yes
510-522 AT&T OKLD ALMD – – yes
510-523 AT&T OKLD ALMD – – yes
510-524 AT&T OKLD BKLY – – yes
510-525 AT&T OKLD BKLY – – yes
510-526 AT&T OKLD BKLY – – yes
510-527 AT&T OKLD BKLY – – yes
510-528 AT&T OKLD BKLY – – yes
510-529 AT&T OKLD BKLY – yes yes
510-530 AT&T OKLD FRTVL – – yes
510-531 AT&T OKLD FRTVL – – yes
510-532 AT&T OKLD FRTVL – – yes
510-533 AT&T OKLD FRTVL – – yes
510-534 AT&T OKLD FRTVL – – yes
510-535 AT&T OKLD FRTVL – – yes
510-536 AT&T OKLD FRTVL – – yes
510-537 AT&T HAYWARD – – yes
510-538 AT&T HAYWARD – – yes
510-539 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – – yes
510-540 AT&T OKLD BKLY – – yes
510-541 AT&T OKLD MN-PD – – yes
510-542 Verizon OKLD BKLY – yes yes
510-543 T-Mobile OKLD MN-PD – yes yes
510-544 Onvoy OKLD TRNID – yes yes
510-545 Verizon OKLD ALMD – yes yes
510-546 Charter HAYWARD 2024-01-04 yes yes
510-547 AT&T OKLD MN-PD – – yes
510-548 AT&T OKLD BKLY – – yes
510-549 AT&T OKLD BKLY – yes yes
510-550 Lumen OKLD MN-PD – yes yes
510-551 T-Mobile OKLD MN-PD – yes yes
510-552 Verizon FRNK MAIN 2001-06-25 yes yes
510-553 AT&T OKLD TRNID – – yes
510-554 33 WIRELESS INC. HAYWARD – – yes
510-556 Lumen FRNK MAIN 2014-05-05 yes yes
510-557 T-Mobile FRNK MAIN 2001-05-17 yes yes
510-558 AT&T OKLD BKLY – yes yes
510-559 AT&T OKLD BKLY – yes yes
510-560 Comcast OKLD TRNID 2014-07-14 yes yes
510-561 AT&T OKLD FRTVL 2017-04-14 yes yes
510-562 AT&T OKLD TRNID – – yes
510-563 AT&T OKLD TRNID – yes yes
510-564 Verizon OKLD TRNID – yes yes
510-565 T-Mobile FRNK MAIN – yes yes
510-566 Verizon HAYWARD – yes yes
510-567 AT&T OKLD TRNID – yes yes
510-568 AT&T OKLD TRNID – – yes
510-569 AT&T OKLD TRNID – – yes
510-570 T-Mobile OKLD BKLY 2016-09-26 yes yes
510-571 AT&T HAYWARD 2017-08-16 yes yes
510-572 Verizon FRNK OLIVR – – yes
510-573 Comcast FRNK OLIVR – yes yes
510-574 AT&T FRNK MAIN – yes yes
510-575 T-Mobile OKLD MN-PD – yes yes
510-576 Verizon HAYWARD – yes yes
510-577 AT&T OKLD TRNID – – yes
510-578 Verizon FRNK MAIN – yes yes
510-579 AT&T FRNK MAIN – – yes
510-580 Verizon FRNK OLIVR – – yes
510-581 AT&T HAYWARD – – yes
510-582 AT&T HAYWARD – – yes
510-583 AT&T HAYWARD – – yes
510-584 Verizon HAYWARD – yes yes
510-585 TPx FRNK MAIN – yes yes
510-586 Comcast HAYWARD – yes yes
510-587 AT&T OKLD MN-PD – yes yes
510-588 Onvoy OKLD MN-PD – yes yes
510-589 AT&T HAYWARD – – yes
510-590 AT&T OKLD MN-PD – yes yes
510-591 AT&T FRNK MAIN 2024-02-20 yes yes
510-592 Lumen HRCUL-RODE – yes yes
510-593 T-Mobile OKLD MN-PD – yes yes
510-594 AT&T OKLD MN-PD – – yes
510-595 AT&T OKLD MN-PD – – yes
510-596 AT&T OKLD MN-PD – yes yes
510-597 AT&T OKLD MN-PD – yes yes
510-598 T-Mobile FRNK MAIN 2013-01-18 yes yes
510-599 AT&T OKLD MN-PD – – yes
510-600 Onvoy HAYWARD – yes yes
510-601 AT&T OKLD MN-PD – yes yes
510-602 Verizon FRNK MAIN 2017-04-04 yes yes
510-603 Comcast OKLD FRTVL 2018-02-20 yes yes
510-604 AT&T OKLD MN-PD – – yes
510-605 Verizon HAYWARD 2018-01-17 yes yes
510-606 Verizon HAYWARD 2010-08-10 yes yes
510-607 TPx OKLD MN-PD 2018-03-16 yes yes
510-608 AT&T FRNK MAIN – yes yes
510-609 T-Mobile RICHMOND 2018-04-11 yes yes
510-610 AT&T OKLD MN-PD – – yes
510-612 AT&T OKLD MN-PD – – yes
510-613 AT&T OKLD TRNID – yes yes
510-614 AT&T OKLD TRNID – – yes
510-615 AT&T OKLD TRNID – – yes
510-616 SONIC TELECOM, LLC - CA OKLD BKLY 2017-12-18 yes yes
510-617 Onvoy HRCUL-RODE 2018-08-31 yes yes
510-618 AT&T OKLD TRNID – yes yes
510-619 Lumen RICHMOND – yes yes
510-620 AT&T RICHMOND – yes yes
510-621 Verizon RICHMOND – yes yes
510-622 AT&T OKLD MN-PD – – yes
510-623 AT&T FRNK OLIVR – yes yes
510-624 AT&T FRNK OLIVR – yes yes
510-625 AT&T OKLD MN-PD – – yes
510-626 Bandwidth OKLD TRNID 2016-07-29 yes yes
510-627 AT&T OKLD MN-PD – yes yes
510-628 AT&T OKLD MN-PD – yes yes
510-629 Lumen OKLD ALMD – yes yes
510-630 T-Mobile ELSBR-PINL 2019-10-16 yes yes
510-631 AT&T OKLD BKLY 2015-10-02 yes yes
510-632 AT&T OKLD TRNID – – yes
510-633 AT&T OKLD TRNID – – yes
510-634 Verizon HAYWARD 2014-09-24 yes yes
510-635 AT&T OKLD TRNID – – yes
510-636 AT&T OKLD TRNID – yes yes
510-637 AT&T OKLD MN-PD – yes yes
510-638 AT&T OKLD TRNID – – yes
510-639 AT&T OKLD TRNID – – yes
510-640 T-Mobile ELSBR-PINL 2015-05-01 yes yes
510-641 AT&T ELSBR-PINL 2020-12-10 yes yes
510-642 AT&T OKLD BKLY – – yes
510-643 AT&T OKLD BKLY – – yes
510-644 AT&T OKLD BKLY – – yes
510-645 AT&T OKLD MN-PD – – yes
510-646 Bandwidth OKLD BKLY 2013-03-07 yes yes
510-647 AT&T OKLD BKLY – yes yes
510-648 AT&T FRNK MAIN – yes yes
510-649 AT&T OKLD BKLY – – yes
510-650 Onvoy ELSBR-PINL 2017-12-21 yes yes
510-651 AT&T FRNK OLIVR – – yes
510-652 AT&T OKLD MN-PD – – yes
510-653 AT&T OKLD MN-PD – – yes
510-654 AT&T OKLD MN-PD – – yes
510-655 AT&T OKLD MN-PD – – yes
510-656 AT&T FRNK OLIVR – – yes
510-657 AT&T FRNK OLIVR – – yes
510-658 AT&T OKLD MN-PD – – yes
510-659 AT&T FRNK OLIVR – yes yes
510-660 AT&T RICHMOND 2015-08-11 yes yes
510-661 AT&T FRNK OLIVR – yes yes
510-662 Verizon ELSBR-PINL – yes yes
510-663 AT&T OKLD MN-PD – – yes
510-664 AT&T OKLD BKLY – – yes
510-665 AT&T OKLD BKLY – yes yes
510-666 AT&T OKLD BKLY – yes yes
510-667 AT&T OKLD TRNID – yes yes
510-668 AT&T FRNK OLIVR – yes yes
510-669 AT&T ELSBR-PINL – yes yes
510-670 AT&T HAYWARD – – yes
510-671 Bandwidth OKLD ALMD 2013-05-14 yes yes
510-672 Verizon RICHMOND 2002-09-19 yes yes
510-673 Verizon FRNK MAIN – – yes
510-674 Onvoy HAYWARD 2014-11-03 yes yes
510-675 AT&T FRNK GRNLF – yes yes
510-676 AT&T FRNK MAIN 2002-06-14 – yes
510-677 T-Mobile HAYWARD 2001-03-22 yes yes
510-678 AT&T OKLD TRNID – – yes
510-679 Verizon OKLD BKLY 2015-04-13 yes yes
510-680 Lumen RICHMOND 2013-06-03 yes yes
510-681 T-Mobile OKLD MN-PD – yes yes
510-682 T-Mobile OKLD ALMD – yes yes
510-683 AT&T FRNK OLIVR – yes yes
510-684 T-Mobile OKLD BKLY – yes yes
510-685 Verizon RICHMOND – – yes
510-686 AT&T OKLD TRNID – yes yes
510-687 AT&T FRNK OLIVR – – yes
510-688 T-Mobile HAYWARD – yes yes
510-689 T-Mobile OKLD FRTVL 2001-04-20 yes yes
510-690 AT&T HAYWARD – yes yes
510-691 T-Mobile HRCUL-RODE 2001-09-19 yes yes
510-692 T-Mobile OKLD TRNID – yes yes
510-693 AT&T OKLD MN-PD – – yes
510-694 Onvoy OKLD ALMD 2014-12-08 yes yes
510-695 Verizon HAYWARD 2007-08-17 yes yes
510-696 T-Mobile OKLD FRTVL 2015-06-22 yes yes
510-697 AT&T OKLD MN-PD – – yes
510-698 TPx OKLD FRTVL – yes yes
510-699 33 WIRELESS INC. OKLD MN-PD – – yes
510-701 AT&T OKLD MN-PD – – yes
510-702 Spok OKLD MN-PD – – yes
510-703 AT&T OKLD MN-PD – – yes
510-704 AT&T OKLD BKLY – yes yes
510-705 AT&T OKLD BKLY – yes yes
510-706 T-Mobile HAYWARD 2001-08-22 – yes
510-707 T-Mobile OKLD TRNID 2016-04-01 yes yes
510-708 AT&T OKLD MN-PD – – yes
510-709 IP HORIZON LLC FRNK MAIN – yes yes
510-710 AT&T OKLD MN-PD – – yes
510-712 AT&T OKLD MN-PD – yes yes
510-713 AT&T FRNK MAIN – – yes
510-714 T-Mobile FRNK MAIN – yes yes
510-715 T-Mobile OKLD MN-PD – yes yes
510-716 Spok OKLD MN-PD – – yes
510-717 T-Mobile OKLD BKLY 2002-09-19 yes yes
510-718 American Messaging OKLD MN-PD – – yes
510-719 T-Mobile OKLD MN-PD – yes yes
510-720 Spok OKLD MN-PD – – yes
510-721 Onvoy OKLD MN-PD 2021-11-18 yes yes
510-722 Bandwidth CROCKETT – yes yes
510-723 AT&T HAYWARD – yes yes
510-724 AT&T ELSBR-PINL – – yes
510-725 Lumen OKLD BKLY – yes yes
510-726 Peerless CROCKETT 2016-08-25 yes yes
510-727 AT&T HAYWARD – yes yes
510-728 AT&T HAYWARD – – yes
510-729 AT&T OKLD TRNID – yes yes
510-730 Bandwidth RICHMOND 2010-02-22 yes yes
510-731 Verizon HAYWARD – yes yes
510-732 AT&T HAYWARD – yes yes
510-733 AT&T HAYWARD – – yes
510-734 AT&T RICHMOND – – yes
510-735 AT&T OKLD MN-PD – yes yes
510-736 T-Mobile HAYWARD 2013-12-09 yes yes
510-737 AT&T FRNK MAIN 2015-11-13 yes yes
510-738 Peerless FRNK OLIVR 2016-08-26 yes yes
510-739 AT&T FRNK MAIN – yes yes
510-740 Verizon OKLD MN-PD – yes yes
510-741 AT&T ELSBR-PINL – – yes
510-742 AT&T FRNK MAIN – – yes
510-743 Verizon FRNK OLIVR – yes yes
510-744 AT&T FRNK MAIN – yes yes
510-745 AT&T FRNK MAIN – yes yes
510-746 TPx OKLD TRNID 2001-04-23 yes yes
510-747 AT&T OKLD ALMD – yes yes
510-748 AT&T OKLD ALMD – – yes
510-749 AT&T OKLD ALMD – – yes
510-750 T-Mobile HAYWARD – yes yes
510-751 Onvoy HAYWARD – yes yes
510-752 AT&T OKLD MN-PD – – yes
510-753 T-Mobile OKLD TRNID 2014-11-25 yes yes
510-754 T-Mobile HAYWARD 2002-05-17 yes yes
510-755 T-Mobile HAYWARD – yes yes
510-756 T-Mobile OKLD TRNID 2015-09-09 yes yes
510-757 T-Mobile OKLD MN-PD – yes yes
510-758 AT&T ELSBR-PINL – – yes
510-759 AT&T OKLD MN-PD – yes yes
510-760 T-Mobile HAYWARD – yes yes
510-761 AT&T OKLD MN-PD – yes yes
510-763 AT&T OKLD MN-PD – – yes
510-764 Lumen OKLD ALMD – yes yes
510-765 AT&T ELSBR-PINL – – yes
510-766 Bandwidth FRNK MAIN 2015-03-25 yes yes
510-767 T-Mobile FRNK MAIN 2019-11-08 yes yes
510-768 Verizon OKLD MN-PD – yes yes
510-769 AT&T OKLD ALMD – – yes
510-770 AT&T FRNK OLIVR – yes yes
510-771 Verizon FRNK OLIVR – yes yes
510-772 T-Mobile OKLD MN-PD – yes yes
510-773 T-Mobile OKLD MN-PD – yes yes
510-774 T-Mobile OKLD MN-PD – yes yes
510-775 Bandwidth OKLD ALMD 2012-09-14 yes yes
510-776 T-Mobile RICHMOND 2001-09-21 – yes
510-777 AT&T OKLD TRNID – yes yes
510-778 Comcast RICHMOND 2006-09-21 yes yes
510-779 Lumen ELSBR-PINL – yes yes
510-780 AT&T HAYWARD – yes yes
510-781 AT&T HAYWARD – yes yes
510-782 AT&T HAYWARD – – yes
510-783 AT&T HAYWARD – – yes
510-784 AT&T HAYWARD – – yes
510-785 AT&T HAYWARD – – yes
510-786 AT&T HAYWARD – yes yes
510-787 AT&T CROCKETT – yes yes
510-788 Verizon OKLD MN-PD – yes yes
510-789 Verizon FRNK MAIN – yes yes
510-790 AT&T FRNK MAIN – – yes
510-791 AT&T FRNK MAIN – – yes
510-792 AT&T FRNK MAIN – – yes
510-793 AT&T FRNK MAIN – – yes
510-794 AT&T FRNK MAIN – – yes
510-795 AT&T FRNK MAIN – – yes
510-796 AT&T FRNK MAIN – – yes
510-797 AT&T FRNK MAIN – – yes
510-798 T-Mobile OKLD TRNID – yes yes
510-799 AT&T HRCUL-RODE – – yes
510-800 Onvoy OKLD ALMD – yes yes
510-801 Spok OKLD MN-PD – – yes
510-802 Spok OKLD MN-PD – – yes
510-803 Verizon HRCUL-RODE – yes yes
510-804 T-Mobile ELSBR-PINL – yes yes
510-805 Spok OKLD MN-PD – – yes
510-806 Lumen RICHMOND 2016-06-09 yes yes
510-807 T-Mobile HAYWARD 2019-05-28 yes yes
510-808 AT&T OKLD MN-PD – yes yes
510-809 TPx OKLD BKLY – yes yes
510-810 T-Mobile OKLD ALMD 2024-05-31 yes yes
510-812 T-Mobile OKLD BKLY – yes yes
510-813 AT&T OKLD MN-PD – – yes
510-814 AT&T OKLD ALMD – – yes
510-815 T-Mobile ELSBR-PINL – yes yes
510-816 AT&T OKLD MN-PD – – yes
510-817 AT&T OKLD MN-PD – yes yes
510-818 AT&T FRNK MAIN – – yes
510-819 Charter HAYWARD 2024-06-12 yes yes
510-820 T-Mobile OKLD TRNID 2015-07-10 yes yes
510-821 Verizon OKLD MN-PD – yes yes
510-822 T-Mobile OKLD TRNID 2016-10-21 yes yes
510-823 T-Mobile OKLD MN-PD – yes yes
510-824 Verizon FRNK OLIVR – yes yes
510-825 T-Mobile HAYWARD 2001-10-18 yes yes
510-826 AT&T HAYWARD 2016-12-09 yes yes
510-827 T-Mobile OKLD MN-PD – yes yes
510-828 Verizon HAYWARD 2001-03-22 yes yes
510-829 T-Mobile RICHMOND 2014-08-18 yes yes
510-830 IP HORIZON LLC OKLD MN-PD – yes yes
510-831 Bandwidth RICHMOND 2020-12-11 yes yes
510-832 AT&T OKLD MN-PD – yes yes
510-833 Comcast OKLD BKLY 2014-07-28 yes yes
510-834 AT&T OKLD MN-PD – – yes
510-835 AT&T OKLD MN-PD – – yes
510-836 AT&T OKLD MN-PD – yes yes
510-837 AT&T RICHMOND – yes yes
510-838 Bandwidth OKLD FRTVL 2014-02-28 yes yes
510-839 AT&T OKLD MN-PD – – yes
510-840 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – – yes
510-841 AT&T OKLD BKLY – – yes
510-842 Verizon OKLD FRTVL – yes yes
510-843 AT&T OKLD BKLY – – yes
510-844 Verizon OKLD MN-PD – yes yes
510-845 AT&T OKLD BKLY – – yes
510-846 Verizon OKLD ALMD – yes yes
510-847 Verizon OKLD BKLY 2001-03-22 – yes
510-848 AT&T OKLD BKLY – – yes
510-849 AT&T OKLD BKLY – yes yes
510-850 T-Mobile OKLD TRNID 2015-04-13 yes yes
510-851 Verizon OKLD MN-PD – yes yes
510-852 Verizon OKLD MN-PD – yes yes
510-853 Verizon OKLD MN-PD – yes yes
510-854 Bandwidth ELSBR-PINL – yes yes
510-855 UTILITY TELECOM GROUP, LLC - CA OKLD MN-PD – yes yes
510-856 Verizon HAYWARD – yes yes
510-857 Verizon FRNK MAIN – yes yes
510-858 T-Mobile OKLD MN-PD – yes yes
510-859 TPx OKLD BKLY – yes yes
510-860 Lumen RICHMOND – yes yes
510-861 AT&T HAYWARD – yes yes
510-862 AT&T HAYWARD – yes yes
510-863 Verizon OKLD ALMD – yes yes
510-864 AT&T OKLD ALMD – – yes
510-865 AT&T OKLD ALMD – – yes
510-866 T-Mobile OKLD FRTVL 2001-01-25 yes yes
510-867 T-Mobile OKLD MN-PD – yes yes
510-868 Lumen OKLD BKLY – yes yes
510-869 AT&T OKLD MN-PD – yes yes
510-870 Lumen FRNK GRNLF – yes yes
510-871 Verizon OKLD ALMD 2014-07-28 yes yes
510-872 T-Mobile OKLD ALMD – yes yes
510-873 AT&T OKLD MN-PD – yes yes
510-874 AT&T OKLD MN-PD – yes yes
510-875 Verizon OKLD TRNID – yes yes
510-876 AT&T HAYWARD 2014-03-27 yes yes
510-877 Verizon OKLD TRNID – yes yes
510-878 Comcast OKLD TRNID – yes yes
510-879 AT&T OKLD MN-PD – yes yes
510-880 Onvoy HAYWARD – yes yes
510-881 AT&T HAYWARD – yes yes
510-882 Verizon OKLD MN-PD – – yes
510-883 AT&T OKLD BKLY – yes yes
510-884 UTILITY TELECOM GROUP, LLC - CA HAYWARD – – yes
510-885 AT&T HAYWARD – – yes
510-886 AT&T HAYWARD – – yes
510-887 AT&T HAYWARD – – yes
510-888 AT&T HAYWARD – – yes
510-889 AT&T HAYWARD – yes yes
510-890 T-Mobile RICHMOND 2016-06-14 yes yes
510-891 AT&T OKLD MN-PD – yes yes
510-892 Onvoy HAYWARD – yes yes
510-893 AT&T OKLD MN-PD – – yes
510-894 Comcast FRNK MAIN – yes yes
510-895 AT&T OKLD TRNID – – yes
510-896 AT&T FRNK MAIN – yes yes
510-897 AT&T FRNK OLIVR – yes yes
510-898 AT&T OKLD BKLY – yes yes
510-899 Bandwidth OKLD MN-PD – yes yes
510-900 Onvoy OKLD BKLY – yes yes
510-901 Bandwidth HAYWARD 2016-07-29 yes yes
510-902 Onvoy FRNK MAIN 2018-12-03 yes yes
510-903 Lumen OKLD MN-PD – yes yes
510-904 Lumen OKLD TRNID 2001-04-20 yes yes
510-905 T-Mobile OKLD ALMD 2018-09-17 yes yes
510-906 Onvoy OKLD ALMD 2016-07-15 yes yes
510-907 Verizon OKLD MN-PD – yes yes
510-908 Verizon OKLD MN-PD – yes yes
510-909 Verizon HAYWARD – – yes
510-910 Verizon OKLD MN-PD – – yes
510-912 Verizon OKLD MN-PD – – yes
510-913 Verizon OKLD MN-PD – yes yes
510-914 Verizon OKLD MN-PD – – yes
510-915 Verizon OKLD MN-PD – – yes
510-916 T-Mobile OKLD TRNID 2021-03-04 yes yes
510-917 Verizon OKLD MN-PD – – yes
510-918 AT&T OKLD MN-PD – – yes
510-919 Verizon OKLD MN-PD – – yes
510-920 SONIC TELECOM, LLC - CA OKLD MN-PD 2018-03-16 yes yes
510-921 AT&T HAYWARD – yes yes
510-922 AT&T OKLD MN-PD – yes yes
510-923 AT&T OKLD MN-PD – – yes
510-924 Lumen OKLD TRNID – yes yes
510-925 Bandwidth HAYWARD 2014-09-18 yes yes
510-926 Verizon OKLD BKLY – yes yes
510-927 Lumen OKLD FRTVL – yes yes
510-928 AT&T OKLD MN-PD – – yes
510-929 Bandwidth OKLD MN-PD 2018-03-13 yes yes
510-930 Peerless OKLD FRTVL 2018-09-20 yes yes
510-931 Lumen HAYWARD – yes yes
510-932 T-Mobile RICHMOND 2001-03-22 yes yes
510-933 TPx FRNK OLIVR 2001-03-01 – yes
510-934 T-Mobile OKLD FRTVL 2015-03-11 yes yes
510-935 AT&T HAYWARD 2014-03-27 yes yes
510-936 AT&T FRNK MAIN – yes yes
510-937 Bandwidth CROCKETT 2015-06-09 yes yes
510-938 T-Mobile FRNK MAIN 2001-09-21 – yes
510-939 Bandwidth HRCUL-RODE 2015-03-25 yes yes
510-940 TPx HAYWARD – yes yes
510-941 Comcast FRNK GRNLF 2016-12-12 yes yes
510-942 AT&T RICHMOND 2014-12-01 yes yes
510-943 Lumen FRNK MAIN – yes yes
510-944 T-Mobile OKLD BKLY 2014-10-03 yes yes
510-945 AT&T FRNK GRNLF 2015-04-10 yes yes
510-946 AT&T FRNK OLIVR 2015-06-11 yes yes
510-947 Onvoy OKLD MN-PD – yes yes
510-948 Verizon HRCUL-RODE 2004-08-18 yes yes
510-949 Onvoy HRCUL-RODE 2016-07-15 yes yes
510-951 Verizon HAYWARD 2021-08-05 yes yes
510-952 T-Mobile FRNK GRNLF 2001-05-17 yes yes
510-953 AT&T FRNK MAIN – yes yes
510-954 Onvoy HAYWARD 2018-12-03 yes yes
510-955 Verizon OKLD TRNID 2018-04-05 yes yes
510-956 Bandwidth OKLD ALMD 2019-01-17 yes yes
510-957 Verizon OKLD TRNID – yes yes
510-960 AT&T OKLD BKLY – yes yes
510-961 Bandwidth FRNK GRNLF 2019-04-17 yes yes
510-962 Lumen HAYWARD – yes yes
510-963 AT&T HAYWARD 2015-11-13 yes yes
510-964 AT&T ELSBR-PINL – yes yes
510-965 AT&T RICHMOND – yes yes
510-966 Charter RICHMOND 2024-07-23 yes yes
510-967 T-Mobile OKLD FRTVL – yes yes
510-968 American Messaging FRNK MAIN – – yes
510-969 Lumen OKLD TRNID – yes yes
510-970 AT&T RICHMOND – – yes
510-971 AT&T OKLD MN-PD 2020-12-22 yes yes
510-972 Comcast FRNK GRNLF – yes yes
510-973 T-Mobile OKLD BKLY 2021-02-25 yes yes
510-974 Lumen RICHMOND 2014-09-19 yes yes
510-975 Verizon OKLD ALMD 2019-01-22 yes yes
510-976 NORTH COUNTY COMMUNICATION CORPORATION - CA OKLD BKLY 2011-06-08 – yes
510-977 FRACTEL, LLC OKLD BKLY 2019-03-19 yes yes
510-978 Lumen OKLD ALMD – yes yes
510-979 AT&T FRNK OLIVR – yes yes
510-980 Verizon FRNK MAIN 2019-06-10 yes yes
510-981 AT&T OKLD BKLY – yes yes
510-982 Verizon OKLD BKLY – yes yes
510-983 Bandwidth FRNK OLIVR 2019-02-06 yes yes
510-984 Lumen OKLD BKLY – yes yes
510-985 AT&T OKLD MN-PD – yes yes
510-986 AT&T OKLD MN-PD – yes yes
510-987 AT&T OKLD MN-PD – yes yes
510-988 T-Mobile OKLD FRTVL 2019-03-21 yes yes
510-989 INTEGRATED PATH COMMUNICATIONS, LLC - CA OKLD BKLY – yes yes
510-990 Onvoy OKLD BKLY – yes yes
510-991 Onvoy FRNK GRNLF – yes yes
510-992 Bandwidth OKLD MN-PD – yes yes
510-993 T-Mobile OKLD BKLY 2016-06-10 yes yes
510-994 Bandwidth RICHMOND 2019-07-26 yes yes
510-995 TPx OKLD ALMD – yes yes
510-996 Lumen FRNK MAIN – yes yes
510-997 American Messaging OKLD MN-PD – – yes
510-998 AT&T ELSBR-PINL 2019-03-27 yes yes
510-999 Onvoy HAYWARD – yes yes

Frequently asked

How many prefixes does area code 510 have?

785 NXX blocks are assigned of 786 possible. Each block is 10,000 consecutive numbers, so the code currently covers about 7,850 thousand-number ranges across 13 rate centers.

What do the first three digits after 510 tell me?

They identify the block, which tells you the rate center it was allocated to and the carrier that received it. They do not tell you who serves the number today: portability moves numbers between carriers, and pooling splits a block between several of them.

Is a 510 prefix tied to a specific town?

To a rate center, which is billing geography rather than a town. NANPA abbreviates rate center names to ten characters and in large metros uses zone codes, so the name is a NANPA label, not a place name.

What does “pooled” mean in the 510 table?

That the block is in thousands-block pooling: carriers draw 1,000-number lots from it instead of taking all 10,000. 514 of 510's blocks are pooled, which is how regulators slowed down area code exhaustion – and why one prefix can belong to several carriers.

Source and limits

NANPA CO Code Assignment Records, all states, utilized codes, file updated 11/01/2026 – the rows where the record's Use field is “AS” (assigned). Unavailable codes are excluded. The records say who received a block and when, not who serves a particular number today.

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