All assignees
800 prefixes in 203 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 203-600 | MERIDEN | 5562 | 2008-10-03 | Yes |
| 203-601 | TRUMBULL | 7143 | — | Yes |
| 203-602 | STAMFORD | 9147 | — | Yes |
| 203-603 | NEW HAVEN | 9147 | — | — |
| 203-604 | NORWALK | 4800 | 2001-03-14 | Yes |
| 203-605 | NEW HAVEN | 6388 | — | — |
| 203-606 | NEW HAVEN | 6624 | — | — |
| 203-607 | STAMFORD | 7230 | 2003-02-04 | Yes |
| 203-608 | MERIDEN | 829J | — | Yes |
| 203-609 | STAMFORD | 9147 | — | Yes |
| 203-610 | BRIDGEPORT | 829J | — | Yes |
| 203-611 | XXXXXXXXXX | MULT | — | — |
| 203-612 | BRIDGEPORT | 4800 | — | Yes |
| 203-613 | NORWALK | 5562 | — | Yes |
| 203-614 | STAMFORD | 9147 | — | Yes |
| 203-615 | BRIDGEPORT | 9147 | — | Yes |
| 203-616 | DANBURY | 4800 | — | Yes |
| 203-617 | DANBURY | 6624 | 2006-09-05 | Yes |
| 203-618 | GREENWICH | 9104 | — | — |
| 203-619 | NEW HAVEN | 9147 | — | Yes |
| 203-620 | DARIEN | 7230 | 2004-07-19 | Yes |
| 203-621 | DARIEN | 829J | — | Yes |
| 203-622 | GREENWICH | 9104 | — | — |
| 203-623 | NEW HAVEN | 6388 | — | — |
| 203-624 | NEW HAVEN | 9147 | — | — |
| 203-625 | GREENWICH | 9104 | — | Yes |
| 203-626 | WALLINGFD | 7421 | — | Yes |
| 203-627 | NEW HAVEN | 6624 | — | Yes |
| 203-628 | DANBURY | 4950 | — | Yes |
| 203-629 | GREENWICH | 9104 | — | — |
| 203-630 | MERIDEN | 9147 | — | — |
| 203-631 | MERIDEN | 4036 | — | — |
| 203-632 | NAUGATUCK | 829J | — | Yes |
| 203-633 | WOLCOTT | 4800 | — | Yes |
| 203-634 | MERIDEN | 9147 | — | — |
| 203-635 | WESTPORT | 4800 | — | Yes |
| 203-636 | DARIEN | 7230 | 2004-09-14 | Yes |
| 203-637 | OLDGRNWICH | 9147 | — | — |
| 203-638 | TRUMBULL | 829J | — | Yes |
| 203-639 | MERIDEN | 9147 | — | — |
| 203-640 | NEW HAVEN | 4036 | — | — |
| 203-641 | NEW HAVEN | 6388 | — | — |
| 203-642 | NORWALK | 7230 | — | Yes |
| 203-643 | BRANFORD | 829J | — | Yes |
| 203-644 | NORWALK | 6388 | — | Yes |
| 203-645 | NEW HAVEN | 4036 | — | — |
| 203-646 | BRANFORD | 639C | — | Yes |
| 203-647 | MILFORD | 829J | — | — |
| 203-648 | DANBURY | 4800 | — | Yes |
| 203-649 | CHESHIRE | 829J | — | Yes |
| 203-650 | BRIDGEPORT | 5562 | 2001-03-26 | Yes |
| 203-651 | CHESHIRE | 829J | — | Yes |
| 203-652 | NEW CANAAN | 829J | — | Yes |
| 203-653 | STAMFORD | 829J | — | Yes |
| 203-654 | NEW HAVEN | 9147 | — | Yes |
| 203-655 | DARIEN | 9147 | — | — |
| 203-656 | DARIEN | 9147 | — | — |
| 203-657 | NEW HAVEN | 9748 | — | — |
| 203-658 | STAMFORD | 7143 | — | Yes |
| 203-659 | FAIRFIELD | 829J | — | Yes |
| 203-660 | BYRAM | 639C | 2001-01-03 | Yes |
| 203-661 | GREENWICH | 9104 | — | — |
| 203-662 | DARIEN | 9147 | — | — |
| 203-663 | NORWALK | 829J | — | Yes |
| 203-664 | REDDING | 612K | — | Yes |
| 203-665 | WILTON | 829J | — | Yes |
| 203-666 | BRIDGEPORT | 4800 | 2013-09-26 | Yes |
| 203-667 | STAMFORD | 6624 | — | Yes |
| 203-668 | NEW HAVEN | 6624 | — | Yes |
| 203-669 | DARIEN | 4800 | — | Yes |
| 203-670 | FAIRFIELD | 6624 | 2021-12-06 | Yes |
| 203-671 | NEW HAVEN | 6388 | — | — |
| 203-672 | NEW HAVEN | 829J | — | — |
| 203-673 | BRIDGEPORT | 7421 | — | Yes |
| 203-674 | STAMFORD | 9147 | — | Yes |
| 203-675 | NEW HAVEN | 6624 | — | Yes |
| 203-676 | NEW HAVEN | 6624 | — | Yes |
| 203-677 | WALLINGFD | 9147 | — | Yes |
| 203-678 | WALLINGFD | 829J | — | Yes |
| 203-679 | WALLINGFD | 9147 | — | Yes |
| 203-680 | NEW HAVEN | 9147 | 2012-10-31 | Yes |
| 203-681 | BYRAM | 9104 | — | Yes |
| 203-682 | WESTPORT | 829J | — | Yes |
| 203-683 | BRIDGEPORT | 829J | — | Yes |
| 203-684 | NEW HAVEN | 5562 | 2008-10-03 | Yes |
| 203-685 | BRIDGEPORT | 6624 | 2001-03-30 | — |
| 203-686 | MERIDEN | 9147 | — | — |
| 203-687 | NEW HAVEN | 4800 | — | Yes |
| 203-688 | NEW HAVEN | 9147 | — | — |
| 203-689 | GUILFORD | 7421 | — | Yes |
| 203-690 | BRIDGEPORT | 6624 | 2008-03-21 | Yes |
| 203-691 | NEW HAVEN | 9147 | — | Yes |
| 203-692 | FAIRFIELD | 4800 | — | Yes |
| 203-693 | MILFORD | 4950 | 2010-07-13 | Yes |
| 203-694 | MERIDEN | 9147 | — | Yes |
| 203-695 | WATERBURY | 9147 | — | Yes |
| 203-696 | BRIDGEPORT | 9147 | — | — |
| 203-697 | WALLINGFD | 9147 | — | Yes |
| 203-698 | OLDGRNWICH | 9147 | — | Yes |
| 203-699 | CHESHIRE | 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.