All assignees
800 prefixes in 303 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 303-600 | DENVER | 7378 | — | Yes |
| 303-601 | DENVER | 6010 | — | — |
| 303-602 | DENVER | 9636 | — | — |
| 303-603 | DENVER | 9636 | — | — |
| 303-604 | DENVER | 9636 | — | — |
| 303-605 | DENVER | 9636 | — | — |
| 303-606 | DENVER | 9636 | — | — |
| 303-607 | DENVER | 9636 | — | Yes |
| 303-608 | DENVER | 9636 | — | — |
| 303-609 | DENVER | 6630 | — | — |
| 303-610 | DENVER | 6630 | — | — |
| 303-611 | XXXXXXXXXX | MULT | — | — |
| 303-612 | DENVER | 6630 | — | — |
| 303-613 | DENVER | 6630 | — | — |
| 303-614 | DENVER | 9636 | — | — |
| 303-615 | DENVER | 9636 | — | — |
| 303-616 | KEENESBURG | 624H | 2021-11-18 | Yes |
| 303-617 | DENVER | 9636 | — | — |
| 303-618 | DENVER | 6010 | — | — |
| 303-619 | DENVER | 6010 | — | — |
| 303-620 | DENVER | 9636 | — | Yes |
| 303-621 | DENVER | 9636 | — | Yes |
| 303-622 | STRASBURG | 2207 | — | Yes |
| 303-623 | DENVER | 9636 | — | — |
| 303-624 | DENVER | 9636 | — | — |
| 303-625 | DENVER | 6118 | — | Yes |
| 303-626 | DENVER | 9636 | — | — |
| 303-627 | DENVER | 9636 | — | — |
| 303-628 | DENVER | 9636 | — | — |
| 303-629 | DENVER | 9636 | — | — |
| 303-630 | DENVER | 9636 | — | Yes |
| 303-631 | DENVER | 9636 | — | — |
| 303-632 | DENVER | 7378 | — | Yes |
| 303-633 | DENVER | 9636 | — | — |
| 303-634 | DENVER | 9636 | — | — |
| 303-635 | DENVER | 9636 | — | Yes |
| 303-636 | DENVER | 9636 | — | Yes |
| 303-637 | DENVER | 9636 | — | — |
| 303-638 | DENVER | 6010 | — | — |
| 303-639 | DENVER | 9636 | — | — |
| 303-640 | DENVER | 9636 | — | — |
| 303-641 | DENVER | 6529 | — | Yes |
| 303-642 | DENVER | 9636 | — | Yes |
| 303-643 | DENVER | 9636 | — | Yes |
| 303-644 | BENNETT | 2186 | — | — |
| 303-645 | DENVER | 9636 | — | Yes |
| 303-646 | DENVER | 9636 | — | Yes |
| 303-647 | DECKERS | 9636 | — | Yes |
| 303-648 | DENVER | 9636 | — | Yes |
| 303-649 | DENVER | 9636 | — | — |
| 303-650 | DENVER | 9636 | — | — |
| 303-651 | LONGMONT | 9636 | — | — |
| 303-652 | LONGMONT | 9636 | — | Yes |
| 303-653 | DENVER | 6118 | — | Yes |
| 303-654 | DENVER | 9636 | — | — |
| 303-655 | DENVER | 9636 | — | — |
| 303-656 | DENVER | 6567 | — | Yes |
| 303-657 | DENVER | 9636 | — | — |
| 303-658 | DENVER | 9636 | — | Yes |
| 303-659 | DENVER | 9636 | — | — |
| 303-660 | DENVER | 9636 | — | — |
| 303-661 | DENVER | 9636 | — | Yes |
| 303-662 | DENVER | 9636 | — | — |
| 303-663 | DENVER | 9636 | — | — |
| 303-664 | DENVER | 9636 | — | — |
| 303-665 | DENVER | 9636 | — | — |
| 303-666 | DENVER | 9636 | — | — |
| 303-667 | DENVER | 6529 | — | — |
| 303-668 | DENVER | 6529 | — | — |
| 303-669 | DENVER | 6529 | — | — |
| 303-670 | DENVER | 9636 | — | — |
| 303-671 | DENVER | 9636 | — | — |
| 303-672 | DENVER | 9636 | — | — |
| 303-673 | DENVER | 9636 | — | — |
| 303-674 | DENVER | 9636 | — | — |
| 303-675 | DENVER | 9636 | — | — |
| 303-676 | DENVER | 9636 | — | Yes |
| 303-677 | DENVER | 9636 | — | — |
| 303-678 | LONGMONT | 9636 | — | — |
| 303-679 | DENVER | 9636 | — | — |
| 303-680 | DENVER | 9636 | — | — |
| 303-681 | DENVER | 9636 | — | Yes |
| 303-682 | LONGMONT | 9636 | — | — |
| 303-683 | DENVER | 9636 | — | — |
| 303-684 | LONGMONT | 9636 | — | — |
| 303-685 | DENVER | 9636 | — | — |
| 303-686 | DENVER | 6630 | — | — |
| 303-687 | DENVER | 6630 | — | — |
| 303-688 | DENVER | 9636 | — | — |
| 303-689 | DENVER | 9636 | — | — |
| 303-690 | DENVER | 9636 | — | — |
| 303-691 | DENVER | 9636 | — | — |
| 303-692 | DENVER | 9636 | — | — |
| 303-693 | DENVER | 9636 | — | — |
| 303-694 | DENVER | 9636 | — | — |
| 303-695 | DENVER | 9636 | — | — |
| 303-696 | DENVER | 9636 | — | — |
| 303-697 | DENVER | 9636 | — | — |
| 303-698 | DENVER | 9636 | — | — |
| 303-699 | DENVER | 9636 | — | — |
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.