All assignees
800 prefixes in 203 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 203-400 | TRUMBULL | 4036 | 2002-02-19 | Yes |
| 203-401 | NEW HAVEN | 9147 | — | Yes |
| 203-402 | HUNTINGTON | 9147 | — | Yes |
| 203-403 | RIDGEFIELD | 7143 | — | Yes |
| 203-404 | NEW HAVEN | 4800 | — | Yes |
| 203-405 | WOODBURY | 829J | 2001-04-04 | Yes |
| 203-406 | STAMFORD | 9147 | — | Yes |
| 203-407 | NEW HAVEN | 9147 | — | Yes |
| 203-408 | REDDING | 199F | — | Yes |
| 203-409 | OLDGRNWICH | 7143 | — | Yes |
| 203-410 | NEW HAVEN | 6624 | — | Yes |
| 203-411 | XXXXXXXXXX | MULT | — | — |
| 203-412 | NEW HAVEN | 9748 | — | — |
| 203-413 | GREENWICH | 829J | — | — |
| 203-414 | BRIDGEPORT | 4036 | — | — |
| 203-415 | NEW HAVEN | 4036 | 2001-04-12 | — |
| 203-416 | BRIDGEPORT | 9147 | — | Yes |
| 203-417 | DANBURY | 4036 | — | — |
| 203-418 | FAIRFIELD | 7143 | — | Yes |
| 203-419 | WATERBURY | 9147 | — | Yes |
| 203-420 | MERIDEN | 9147 | — | — |
| 203-421 | MADISON | 9147 | — | Yes |
| 203-422 | GREENWICH | 9104 | — | Yes |
| 203-423 | WILTON | 7143 | — | Yes |
| 203-424 | DARIEN | 5562 | 2007-06-29 | Yes |
| 203-425 | STAMFORD | 9147 | — | — |
| 203-426 | NEWTOWN | 9147 | — | — |
| 203-427 | MERIDEN | 7229 | — | Yes |
| 203-428 | STAMFORD | 7230 | — | Yes |
| 203-429 | WESTPORT | 7230 | — | Yes |
| 203-430 | NEW HAVEN | 4036 | — | — |
| 203-431 | RIDGEFIELD | 9147 | — | — |
| 203-432 | NEW HAVEN | 199F | — | — |
| 203-433 | BRANFORD | 318J | — | Yes |
| 203-434 | NORWALK | 6624 | — | — |
| 203-435 | NEW HAVEN | 6624 | — | — |
| 203-436 | NEW HAVEN | 9147 | — | — |
| 203-437 | WATERBURY | 7229 | — | Yes |
| 203-438 | RIDGEFIELD | 9147 | — | — |
| 203-439 | CHESHIRE | 318J | — | Yes |
| 203-440 | MERIDEN | 318J | — | Yes |
| 203-441 | WOLCOTT | 7143 | — | Yes |
| 203-442 | NEW CANAAN | 7143 | — | Yes |
| 203-443 | MERIDEN | 7229 | — | Yes |
| 203-444 | NEW HAVEN | 4036 | — | — |
| 203-445 | TRUMBULL | 9147 | — | Yes |
| 203-446 | ANSONIDRBY | 7143 | — | Yes |
| 203-447 | HUNTINGTON | 7143 | — | Yes |
| 203-448 | DANBURY | 7230 | — | Yes |
| 203-449 | BRIDGEPORT | 5562 | — | Yes |
| 203-450 | BRIDGEPORT | 6388 | 2008-05-12 | Yes |
| 203-451 | WESTPORT | 4036 | — | — |
| 203-452 | TRUMBULL | 9147 | — | — |
| 203-453 | GUILFORD | 9147 | — | — |
| 203-454 | WESTPORT | 9147 | — | — |
| 203-455 | BRIDGEPORT | 7230 | — | Yes |
| 203-456 | DANBURY | 6388 | 2011-12-06 | Yes |
| 203-457 | GUILFORD | 9147 | — | Yes |
| 203-458 | GUILFORD | 9147 | — | — |
| 203-459 | TRUMBULL | 9147 | — | — |
| 203-460 | DANBURY | 5562 | — | Yes |
| 203-461 | STAMFORD | 9147 | — | Yes |
| 203-462 | STAMFORD | 9147 | — | — |
| 203-463 | SEYMOUR | 7143 | — | Yes |
| 203-464 | NEW HAVEN | 6388 | — | — |
| 203-465 | WATERBURY | 9147 | — | Yes |
| 203-466 | NEW HAVEN | 9147 | — | Yes |
| 203-467 | NEW HAVEN | 9147 | — | — |
| 203-468 | NEW HAVEN | 9147 | — | — |
| 203-469 | NEW HAVEN | 9147 | — | — |
| 203-470 | DANBURY | 6388 | — | — |
| 203-471 | XXXXXXXXXX | 9147 | — | — |
| 203-472 | XXXXXXXXXX | 9147 | — | — |
| 203-473 | XXXXXXXXXX | 9147 | — | — |
| 203-474 | XXXXXXXXXX | 9147 | — | — |
| 203-475 | XXXXXXXXXX | MULT | — | — |
| 203-476 | XXXXXXXXXX | 9147 | — | — |
| 203-477 | NEW HAVEN | 6630 | — | — |
| 203-478 | XXXXXXXXXX | 9147 | — | — |
| 203-479 | NEW HAVEN | 9147 | — | Yes |
| 203-480 | FAIRFIELD | 7230 | — | Yes |
| 203-481 | BRANFORD | 9147 | — | — |
| 203-482 | DANBURY | 4036 | 2001-03-23 | Yes |
| 203-483 | BRANFORD | 9147 | — | — |
| 203-484 | BRANFORD | 9147 | — | Yes |
| 203-485 | GREENWICH | 4950 | — | Yes |
| 203-486 | WOODBURY | 9147 | — | Yes |
| 203-487 | STAMFORD | 4800 | 2001-01-03 | Yes |
| 203-488 | BRANFORD | 9147 | — | — |
| 203-489 | GREENWICH | 4950 | 2011-05-25 | Yes |
| 203-490 | NAUGATUCK | 7143 | — | Yes |
| 203-491 | NEWTOWN | 199F | 2010-02-12 | Yes |
| 203-492 | NEW HAVEN | 9147 | — | Yes |
| 203-493 | GEORGETOWN | 4800 | — | Yes |
| 203-494 | NEW HAVEN | 6388 | — | — |
| 203-495 | NEW HAVEN | 9147 | — | — |
| 203-496 | GREENWICH | 5562 | — | Yes |
| 203-497 | NEW HAVEN | 9147 | — | Yes |
| 203-498 | NEW HAVEN | 9147 | — | — |
| 203-499 | NEW HAVEN | 9147 | — | 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.