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 425
QWEST CORPORATION 69
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
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Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
2008-02-13 425-440 0–9 XXXall 10 · 6 holders which blocks → QWEST CORPORATION 9638 BELLEVUE WA
2006-10-04 425-457 0–9 XXXall 10 · 4 holders which blocks → QWEST CORPORATION 9638 BELLEVUE WA
2005-08-31 425-383 0–9 XXXwhole prefix which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-203 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-204 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-208 1XXX2XXX5XXX6XXX9XXX which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-226 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-227 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-228 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-234 none assigned yet which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-235 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-251 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-254 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-255 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-271 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-277 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-291 6XXX7XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-313 not yet reported which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-369 4XXX7XXX · 2 holders which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-373 6XXX which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-378 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-391 not yet reported which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-392 not yet reported which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-394 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-401 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-413 not yet reported which blocks → QWEST CORPORATION 9638 MAPLE VLY WA
— 425-427 not yet reported which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-430 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA
— 425-432 not yet reported which blocks → QWEST CORPORATION 9638 MAPLE VLY WA
— 425-433 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 MAPLE VLY WA
— 425-450 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-451 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-452 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-453 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-454 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-455 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-456 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-462 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-467 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-468 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-557 not yet reported which blocks → QWEST CORPORATION 9638 ISSAQUAH WA
— 425-562 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-564 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-590 7XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-603 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-614 5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-635 8XXX which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-637 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-638 2XXX3XXX9XXX which blocks → QWEST CORPORATION 9638 BELLEVUE WA
— 425-641 not yet reported which blocks → QWEST CORPORATION 9638 BELLEVUE WA

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.