All assignees
800 prefixes in 410 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 410-300 | ELKRIDGE | 5562 | 2004-07-15 | Yes |
| 410-301 | BALTIMORE | 6855 | 2011-10-06 | Yes |
| 410-302 | CATONSVL | 4036 | — | — |
| 410-303 | BALTIMORE | 6395 | — | — |
| 410-304 | QUEENSTOWN | 228C | 2006-03-29 | Yes |
| 410-305 | ODENTON | 9212 | — | Yes |
| 410-306 | ABERDEEN | 9212 | — | Yes |
| 410-307 | TOWSON | 9212 | — | Yes |
| 410-308 | TOWSON | 9212 | — | — |
| 410-309 | COLUMBIA | 9212 | — | — |
| 410-310 | EASTON | 6395 | — | — |
| 410-311 | XXXXXXXXXX | MULT | — | — |
| 410-312 | COLUMBIA | 9212 | — | — |
| 410-313 | ELLICOTTCY | 9212 | — | — |
| 410-314 | ARBUTUS | 7228 | — | Yes |
| 410-315 | SEVERNA PK | 9212 | — | Yes |
| 410-316 | COCKEYSVL | 9212 | — | Yes |
| 410-317 | ARGRGBSNIS | 7228 | — | Yes |
| 410-318 | BALTIMORE | 9212 | — | Yes |
| 410-319 | BALTIMORE | 9212 | — | Yes |
| 410-320 | ANNAPOLIS | 6855 | — | Yes |
| 410-321 | TOWSON | 9212 | — | — |
| 410-322 | BEL AIR | 4036 | — | — |
| 410-323 | BALTIMORE | 9212 | — | — |
| 410-324 | TOWSON | 9212 | — | Yes |
| 410-325 | BALTIMORE | 9212 | — | Yes |
| 410-326 | SOLOMONS | 9212 | — | — |
| 410-327 | BALTIMORE | 9212 | — | — |
| 410-328 | BALTIMORE | 9212 | — | — |
| 410-329 | COCKEYSVL | 9212 | — | Yes |
| 410-330 | CAMBRIDGE | 4036 | — | Yes |
| 410-331 | ELKRIDGE | 6630 | — | — |
| 410-332 | BALTIMORE | 9212 | — | — |
| 410-333 | BALTIMORE | 9212 | — | — |
| 410-334 | SALISBURY | 9212 | — | Yes |
| 410-335 | CHASE | 9212 | — | — |
| 410-336 | BALTIMORE | 4036 | — | — |
| 410-337 | TOWSON | 9212 | — | — |
| 410-338 | BALTIMORE | 9212 | — | Yes |
| 410-339 | TOWSON | 9212 | — | Yes |
| 410-340 | BALTIMORE | 4036 | — | — |
| 410-341 | SALISBURY | 9212 | — | — |
| 410-342 | BALTIMORE | 9212 | — | — |
| 410-343 | SPARKSGLNC | 9212 | — | Yes |
| 410-344 | CHASE | 9212 | — | Yes |
| 410-345 | PIKESVILLE | 9212 | — | Yes |
| 410-346 | SILVER RUN | 9212 | — | Yes |
| 410-347 | BALTIMORE | 9212 | — | — |
| 410-348 | STILL POND | 9212 | — | Yes |
| 410-349 | ANNAPOLIS | 9212 | — | Yes |
| 410-350 | BALTIMORE | 9212 | — | Yes |
| 410-351 | BALTIMORE | 6630 | — | — |
| 410-352 | BISHOPVL | 9212 | — | Yes |
| 410-353 | ANNAPOLIS | 6395 | — | — |
| 410-354 | BALTIMORE | 9212 | — | — |
| 410-355 | BALTIMORE | 9212 | — | — |
| 410-356 | PIKESVILLE | 9212 | — | — |
| 410-357 | PARKTON | 9212 | — | Yes |
| 410-358 | BALTIMORE | 9212 | — | — |
| 410-359 | BALTIMORE | 9212 | — | — |
| 410-360 | ARGRGBSNIS | 9212 | — | — |
| 410-361 | BALTIMORE | 9212 | — | Yes |
| 410-362 | BALTIMORE | 9212 | — | — |
| 410-363 | PIKESVILLE | 9212 | — | — |
| 410-364 | HILLSBORO | 9212 | — | Yes |
| 410-365 | BALTIMORE | 6855 | — | Yes |
| 410-366 | BALTIMORE | 9212 | — | — |
| 410-367 | BALTIMORE | 9212 | — | — |
| 410-368 | BALTIMORE | 9212 | — | Yes |
| 410-369 | BALTIMORE | 7591 | — | Yes |
| 410-370 | CATONSVL | 4036 | — | — |
| 410-371 | BALTIMORE | 6395 | — | — |
| 410-372 | TOWSON | 9212 | — | Yes |
| 410-373 | TOWSON | 6630 | — | — |
| 410-374 | HAMPSTEAD | 9212 | — | Yes |
| 410-375 | BALTIMORE | 6395 | — | — |
| 410-376 | VIENNA | 9212 | — | Yes |
| 410-377 | TOWSON | 9212 | — | — |
| 410-378 | PT DEPOSIT | 9212 | — | Yes |
| 410-379 | ELKRIDGE | 9212 | — | — |
| 410-380 | SALISBURY | 6810 | — | — |
| 410-381 | COLUMBIA | 9212 | — | — |
| 410-382 | BALTIMORE | 6395 | — | — |
| 410-383 | BALTIMORE | 9212 | — | — |
| 410-384 | SEVERNA PK | 9212 | — | Yes |
| 410-385 | BALTIMORE | 9212 | — | — |
| 410-386 | WESTMINSTR | 9212 | — | — |
| 410-387 | BALTIMORE | 829J | 2011-08-12 | Yes |
| 410-388 | SPARROWSPT | 9212 | — | — |
| 410-389 | BALTIMORE | 6630 | — | — |
| 410-390 | OCEAN CITY | 7325 | 2009-06-10 | Yes |
| 410-391 | ESSEX | 9212 | — | — |
| 410-392 | ELKTON | 9212 | — | — |
| 410-393 | BALTIMORE | 9212 | — | — |
| 410-394 | SOLOMONS | 9212 | — | Yes |
| 410-395 | ARBUTUS | 9212 | — | Yes |
| 410-396 | BALTIMORE | 9212 | — | — |
| 410-397 | WINGATE | 9212 | — | Yes |
| 410-398 | ELKTON | 9212 | — | — |
| 410-399 | BEL AIR | 9212 | — | 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.