NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026

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 541
QWEST CORPORATION 184
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
2012-08-01 541-507 0–9 XXXall 10 · 5 holders which blocks → QWEST CORPORATION 9638 GRANTSPASS OR
2008-06-17 541-375 0–9 XXXall 10 · 4 holders which blocks → QWEST CORPORATION 9638 ROSEBURG OR
2007-11-02 541-222 0–9 XXXall 10 · 2 holders which blocks → QWEST CORPORATION 9638 EUGENE OR
2007-02-21 541-516 0–9 XXXall 10 · 6 holders which blocks → QWEST CORPORATION 9638 REDMOND OR
2006-08-23 541-637 0–9 XXXall 10 · 3 holders which blocks → QWEST CORPORATION 9638 ROSEBURG OR
2006-02-03 541-633 0–9 XXXall 10 · 5 holders which blocks → QWEST CORPORATION 9638 BEND OR
2004-09-28 541-789 0–9 XXXwhole prefix which blocks → QWEST CORPORATION 9638 MEDFORD OR
2003-10-30 541-526 0–9 XXXall 10 · 5 holders which blocks → QWEST CORPORATION 9638 REDMOND OR
2002-10-16 541-817 0–9 XXXall 10 · 2 holders which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-201 2XXX3XXX4XXX8XXX · 2 holders which blocks → QWEST CORPORATION 9638 ASHLAND OR
— 541-242 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-245 not yet reported which blocks → QWEST CORPORATION 9638 MEDFORD OR
— 541-262 0XXX1XXX2XXX4XXX5XXX6XXX7XXX · 4 holders which blocks → QWEST CORPORATION 9638 OREGONSLOP OR
— 541-265 not yet reported which blocks → QWEST CORPORATION 9638 NEWPORT OR
— 541-268 5XXX which blocks → QWEST CORPORATION 9638 MAPLETON OR
— 541-273 not yet reported which blocks → QWEST CORPORATION 9638 KLAMATHFLS OR
— 541-276 not yet reported which blocks → QWEST CORPORATION 9638 PENDLETON OR
— 541-278 not yet reported which blocks → QWEST CORPORATION 9638 PENDLETON OR
— 541-282 3XXX4XXX which blocks → QWEST CORPORATION 9638 MEDFORD OR
— 541-302 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-312 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-317 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-318 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-322 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-325 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 MADRAS OR
— 541-327 4XXX5XXX6XXX9XXX · 4 holders which blocks → QWEST CORPORATION 9638 JEFFERSON OR
— 541-330 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-334 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-335 1XXX9XXX which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-336 6XXX which blocks → QWEST CORPORATION 9638 TOLEDO OR
— 541-338 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-341 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-342 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-343 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-344 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-345 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-346 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-349 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-372 6XXX which blocks → QWEST CORPORATION 9638 NYSSA OR
— 541-382 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-383 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-385 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-388 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-389 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-416 not yet reported which blocks → QWEST CORPORATION 9638 PRINEVILLE OR
— 541-431 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-434 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-440 not yet reported which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-444 0XXX3XXX5XXX6XXX · 2 holders which blocks → QWEST CORPORATION 9638 SILETZ OR
— 541-447 not yet reported which blocks → QWEST CORPORATION 9638 PRINEVILLE OR

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.