All assignees
800 prefixes in 303 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 303-700 | — | — | ||
| 303-701 | DENVER | 6907 | — | — |
| 303-702 | LONGMONT | 9636 | — | — |
| 303-703 | DENVER | 9636 | — | — |
| 303-704 | DENVER | 7229 | — | Yes |
| 303-705 | DENVER | 9636 | — | — |
| 303-706 | DENVER | 9636 | — | — |
| 303-707 | DENVER | 9636 | — | — |
| 303-708 | DENVER | 9636 | — | — |
| 303-709 | LONGMONT | 6567 | — | Yes |
| 303-710 | FORTLUPTON | 6567 | — | Yes |
| 303-711 | XXXXXXXXXX | MULT | — | — |
| 303-712 | DENVER | 9636 | — | — |
| 303-713 | DENVER | 9636 | — | — |
| 303-714 | DENVER | 9636 | — | — |
| 303-715 | DENVER | 9636 | — | Yes |
| 303-716 | DENVER | 9636 | — | — |
| 303-717 | FORTLUPTON | 6010 | — | — |
| 303-718 | FORTLUPTON | 6567 | — | Yes |
| 303-719 | DEER TRAIL | 6118 | 2006-11-16 | Yes |
| 303-720 | FORTLUPTON | 6567 | 2008-06-13 | Yes |
| 303-721 | DENVER | 9636 | — | — |
| 303-722 | DENVER | 9636 | — | — |
| 303-723 | DENVER | 7378 | — | — |
| 303-724 | DENVER | 9636 | — | — |
| 303-725 | DENVER | 6529 | — | Yes |
| 303-726 | DENVER | 6567 | — | — |
| 303-727 | DENVER | 9636 | — | Yes |
| 303-728 | DENVER | 7378 | — | Yes |
| 303-729 | DENVER | 7229 | — | — |
| 303-730 | DENVER | 9636 | — | — |
| 303-731 | DENVER | 6118 | — | Yes |
| 303-732 | KEENESBURG | 9636 | — | Yes |
| 303-733 | DENVER | 9636 | — | — |
| 303-734 | DENVER | 9636 | — | — |
| 303-735 | DENVER | 9636 | — | — |
| 303-736 | DENVER | 7378 | — | Yes |
| 303-737 | DENVER | 9636 | — | — |
| 303-738 | DENVER | 9636 | — | — |
| 303-739 | DENVER | 9636 | — | — |
| 303-740 | DENVER | 9636 | — | — |
| 303-741 | DENVER | 9636 | — | — |
| 303-742 | DENVER | 9636 | — | — |
| 303-743 | DENVER | 9636 | — | — |
| 303-744 | DENVER | 9636 | — | — |
| 303-745 | DENVER | 9636 | — | — |
| 303-746 | LONGMONT | 6567 | — | Yes |
| 303-747 | ALLNSPKLYN | 9636 | — | Yes |
| 303-748 | DENVER | 6010 | — | — |
| 303-749 | DENVER | 7378 | — | Yes |
| 303-750 | DENVER | 9636 | — | — |
| 303-751 | DENVER | 9636 | — | — |
| 303-752 | DENVER | 9636 | — | — |
| 303-753 | DENVER | 9636 | — | — |
| 303-754 | DENVER | 9636 | — | — |
| 303-755 | DENVER | 9636 | — | — |
| 303-756 | DENVER | 9636 | — | — |
| 303-757 | DENVER | 9636 | — | — |
| 303-758 | DENVER | 9636 | — | — |
| 303-759 | DENVER | 9636 | — | — |
| 303-760 | DENVER | 6630 | — | — |
| 303-761 | DENVER | 9636 | — | — |
| 303-762 | DENVER | 9636 | — | — |
| 303-763 | DENVER | 9636 | — | Yes |
| 303-764 | DENVER | 9636 | — | — |
| 303-765 | DENVER | 9636 | — | — |
| 303-766 | DENVER | 9636 | — | — |
| 303-767 | DENVER | 9748 | — | — |
| 303-768 | DENVER | 9636 | — | — |
| 303-769 | DEER TRAIL | 2181 | — | — |
| 303-770 | DENVER | 9636 | — | — |
| 303-771 | DENVER | 9636 | — | — |
| 303-772 | LONGMONT | 9636 | — | — |
| 303-773 | DENVER | 9636 | — | — |
| 303-774 | LONGMONT | 9636 | — | — |
| 303-775 | LONGMONT | 6567 | — | — |
| 303-776 | LONGMONT | 9636 | — | — |
| 303-777 | DENVER | 9636 | — | — |
| 303-778 | DENVER | 9636 | — | — |
| 303-779 | DENVER | 9636 | — | — |
| 303-780 | DENVER | 9636 | — | — |
| 303-781 | DENVER | 9636 | — | — |
| 303-782 | DENVER | 9636 | — | — |
| 303-783 | DENVER | 9636 | — | — |
| 303-784 | DENVER | 9636 | — | — |
| 303-785 | DENVER | 7229 | — | — |
| 303-786 | DENVER | 9636 | — | — |
| 303-787 | DENVER | 9636 | — | — |
| 303-788 | DENVER | 9636 | — | — |
| 303-789 | DENVER | 9636 | — | — |
| 303-790 | DENVER | 9636 | — | — |
| 303-791 | DENVER | 9636 | — | — |
| 303-792 | DENVER | 9636 | — | — |
| 303-793 | DENVER | 9636 | — | — |
| 303-794 | DENVER | 9636 | — | — |
| 303-795 | DENVER | 9636 | — | — |
| 303-796 | DENVER | 9636 | — | — |
| 303-797 | DENVER | 9636 | — | — |
| 303-798 | DENVER | 9636 | — | — |
| 303-799 | 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.