NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026

Full prefixes (NXX) Thousands-blocks (1,000-number pools)

The Code holder is who opened each NPA-NXX prefix — not necessarily who holds the numbers. A prefix is 10,000 numbers, but under pooling its ten 1,000-number blocks are handed out individually, often to different carriers; the code holder may hold only one block, or none. The Thousands-blocks column shows how the ten blocks are really split — click which blocks → to see who holds each 1,000-number block and its last-4-digit range. Assignments are initial assignments; the current serving carrier may differ due to portability.

Most active assignees, all time — NPA 503
QWEST CORPORATION 222
New assignments by month Sep 2026 Aug 2026 Jul 2026 Jun 2026 May 2026 Apr 2026 Mar 2026 Feb 2026 Jan 2026 Dec 2025 Nov 2025 Oct 2025
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 503-653 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-654 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-655 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-656 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-657 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-659 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-675 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-697 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-699 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-717 5XXX6XXX · 2 holders which blocks → QWEST CORPORATION 9638 SEASIDE OR
— 503-721 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-722 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-723 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-725 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-727 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-731 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-733 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-735 5XXX which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-736 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-737 4XXX5XXX7XXX8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-738 1XXX which blocks → QWEST CORPORATION 9638 SEASIDE OR
— 503-742 3XXX which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-751 1XXX2XXX3XXX8XXX9XXX · 4 holders which blocks → QWEST CORPORATION 9638 DALLAS OR
— 503-760 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-761 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-762 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-763 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-768 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-771 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-772 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-774 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-775 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-777 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-778 none assigned yet which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-785 3XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-786 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-787 7XXX which blocks → QWEST CORPORATION 9638 FALLS CITY OR
— 503-788 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-790 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-794 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-795 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-796 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-797 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-813 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-823 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-827 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-831 7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 DALLAS OR
— 503-833 2XXX which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-838 not yet reported which blocks → QWEST CORPORATION 9638 DALLAS OR
— 503-856 2XXX4XXX5XXX6XXX · 2 holders which blocks → QWEST CORPORATION 9638 SALEM OR

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.