All assignees
768 prefixes in 603 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 603-500 | TILTON | 965H | 2020-06-15 | Yes |
| 603-501 | PORTSMOUTH | 829J | — | Yes |
| 603-502 | PORTSMOUTH | 4036 | — | — |
| 603-503 | LANCASTER | 7778 | — | Yes |
| 603-504 | CLAREMONT | 6290 | — | Yes |
| 603-505 | DERRY | 6386 | 2002-10-09 | Yes |
| 603-506 | MANCHESTER | 4036 | 2018-10-29 | Yes |
| 603-507 | ROCHESTER | 4036 | 2015-07-28 | Yes |
| 603-508 | PELHAM | 6386 | 2001-08-08 | Yes |
| 603-509 | ROCHESTER | 829J | 2001-09-24 | Yes |
| 603-510 | MERIDEN | 318J | 2010-03-29 | Yes |
| 603-511 | XXXXXXXXXX | MULT | — | — |
| 603-512 | MANCHESTER | 6889 | — | Yes |
| 603-513 | CONCORD | 6386 | — | Yes |
| 603-514 | NASHUA | 6386 | 2021-01-21 | Yes |
| 603-515 | WOLFEBORO | 5113 | — | Yes |
| 603-516 | DOVER | 8468 | — | — |
| 603-517 | MERRIMACK | 9748 | — | — |
| 603-518 | MANCHESTER | 7421 | — | Yes |
| 603-519 | EXETER | 6386 | 2018-10-04 | Yes |
| 603-520 | LACONIA | 6386 | — | — |
| 603-521 | NASHUA | 7421 | — | Yes |
| 603-522 | SANBORNVL | 5113 | — | Yes |
| 603-523 | CANAAN | 5113 | — | Yes |
| 603-524 | LACONIA | 5113 | — | — |
| 603-525 | HANCOCK | 5113 | — | Yes |
| 603-526 | NEW LONDON | 0045 | — | — |
| 603-527 | LACONIA | 5113 | — | Yes |
| 603-528 | LACONIA | 5113 | — | — |
| 603-529 | WEARE | 0039 | — | — |
| 603-530 | BRISTOL | 6386 | 2002-02-22 | Yes |
| 603-531 | PORTSMOUTH | 4036 | — | Yes |
| 603-532 | JAFFREY | 5113 | — | Yes |
| 603-533 | MERRIMACK | 6290 | — | Yes |
| 603-534 | DOVER | 6386 | — | — |
| 603-535 | PLYMOUTH | 829J | — | — |
| 603-536 | PLYMOUTH | 5113 | — | — |
| 603-537 | DERRY | 5113 | — | Yes |
| 603-538 | PITTSBURG | 5113 | — | Yes |
| 603-539 | CTROSSIPEE | 5113 | — | Yes |
| 603-540 | MANCHESTER | 6386 | 2001-08-21 | Yes |
| 603-541 | MANCHESTER | 383J | 2001-05-21 | Yes |
| 603-542 | CLAREMONT | 5113 | — | — |
| 603-543 | CLAREMONT | 5113 | — | Yes |
| 603-544 | MELVIN VLG | 3320 | — | Yes |
| 603-545 | CONCORD | 829J | — | Yes |
| 603-546 | NASHUA | 829J | — | Yes |
| 603-547 | GREENFIELD | 5113 | — | Yes |
| 603-548 | DERRY | 6386 | — | — |
| 603-549 | DERRY | 5113 | — | — |
| 603-550 | DOVER | 073H | — | Yes |
| 603-551 | MANCHESTER | 5113 | — | — |
| 603-552 | DERRY | 7778 | — | Yes |
| 603-553 | DERRY | 4036 | — | — |
| 603-554 | MILFORD | 6290 | — | Yes |
| 603-555 | DIR ASST | MULT | — | — |
| 603-556 | LACONIA | 4017 | — | Yes |
| 603-557 | NASHUA | 6889 | — | Yes |
| 603-558 | CLAREMONT | 6386 | — | Yes |
| 603-559 | PORTSMOUTH | 5113 | — | — |
| 603-560 | SALEM | 4036 | — | Yes |
| 603-561 | NASHUA | 5113 | — | — |
| 603-562 | PETERBROGH | 6290 | — | Yes |
| 603-563 | DUBLIN | 5113 | — | Yes |
| 603-564 | MANCHESTER | 5113 | — | — |
| 603-565 | PENACOOK | 4017 | — | Yes |
| 603-566 | NASHUA | 6386 | — | — |
| 603-567 | PETERBROGH | 4017 | — | Yes |
| 603-568 | CONCORD | 6386 | 2002-08-06 | Yes |
| 603-569 | WOLFEBORO | 5113 | — | — |
| 603-570 | PORTSMOUTH | 8299 | — | Yes |
| 603-571 | DERRY | 4036 | — | Yes |
| 603-573 | CONCORD | 7778 | — | Yes |
| 603-574 | ALSTEAD | 4017 | — | Yes |
| 603-575 | LITTLETON | 7778 | — | Yes |
| 603-576 | ORFORD | 4017 | — | Yes |
| 603-577 | NASHUA | 5113 | — | Yes |
| 603-578 | NASHUA | 5113 | — | — |
| 603-579 | NASHUA | 5113 | — | — |
| 603-580 | EXETER | 318J | — | Yes |
| 603-581 | LACONIA | 829J | — | Yes |
| 603-582 | MERRIMACK | 6290 | — | Yes |
| 603-583 | EXETER | 4017 | — | Yes |
| 603-584 | CONCORD | 6889 | 2021-06-29 | Yes |
| 603-585 | FITZWILLIM | 5113 | — | Yes |
| 603-586 | JEFFERSON | 5113 | — | Yes |
| 603-587 | CANDIA | 7778 | — | Yes |
| 603-588 | ANTRIM | 3320 | — | Yes |
| 603-589 | NASHUA | 829J | — | Yes |
| 603-590 | DURHAM | 8468 | — | Yes |
| 603-591 | MANCHESTER | 6889 | — | Yes |
| 603-592 | SPOFFORD | 7778 | — | Yes |
| 603-593 | JAFFREY | 829J | 2003-06-26 | Yes |
| 603-594 | NASHUA | 5113 | — | — |
| 603-595 | NASHUA | 5113 | — | — |
| 603-596 | NASHUA | 5113 | — | — |
| 603-597 | LYME | 7778 | — | Yes |
| 603-598 | NASHUA | 5113 | — | — |
| 603-599 | NASHUA | 5113 | — | — |
| 603-600 | MANCHESTER | 939H | 2020-05-29 | 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.