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 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
— 541-449 0XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → QWEST CORPORATION 9638 STANFIELD OR
— 541-459 not yet reported which blocks → QWEST CORPORATION 9638 OAKLAND OR
— 541-461 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-463 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-464 not yet reported which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-465 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-471 not yet reported which blocks → QWEST CORPORATION 9638 GRANTSPASS OR
— 541-472 not yet reported which blocks → QWEST CORPORATION 9638 GRANTSPASS OR
— 541-473 7XXX which blocks → QWEST CORPORATION 9638 VALE OR
— 541-474 not yet reported which blocks → QWEST CORPORATION 9638 GRANTSPASS OR
— 541-475 not yet reported which blocks → QWEST CORPORATION 9638 MADRAS OR
— 541-476 not yet reported which blocks → QWEST CORPORATION 9638 GRANTSPASS OR
— 541-479 not yet reported which blocks → QWEST CORPORATION 9638 GRANTSPASS OR
— 541-482 not yet reported which blocks → QWEST CORPORATION 9638 ASHLAND OR
— 541-484 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-485 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-488 not yet reported which blocks → QWEST CORPORATION 9638 ASHLAND OR
— 541-504 6XXX which blocks → QWEST CORPORATION 9638 REDMOND OR
— 541-512 4XXX5XXX6XXX7XXX · 2 holders which blocks → QWEST CORPORATION 9638 PHOENIX OR
— 541-523 not yet reported which blocks → QWEST CORPORATION 9638 BAKER OR
— 541-524 3XXX4XXX5XXX6XXX · 4 holders which blocks → QWEST CORPORATION 9638 BAKER OR
— 541-535 not yet reported which blocks → QWEST CORPORATION 9638 PHOENIX OR
— 541-536 4XXX which blocks → QWEST CORPORATION 9638 LAPINE OR
— 541-546 0XXX1XXX4XXX · 2 holders which blocks → QWEST CORPORATION 9638 CULVER OR
— 541-548 not yet reported which blocks → QWEST CORPORATION 9638 REDMOND OR
— 541-549 not yet reported which blocks → QWEST CORPORATION 9638 SISTERS OR
— 541-552 3XXX4XXX · 2 holders which blocks → QWEST CORPORATION 9638 ASHLAND OR
— 541-553 not yet reported which blocks → QWEST CORPORATION 9638 MADRAS OR
— 541-558 none assigned yet which blocks → QWEST CORPORATION 9638 STATELINE OR
— 541-564 not yet reported which blocks → QWEST CORPORATION 9638 HERMISTON OR
— 541-566 4XXX6XXX7XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9638 ATHENA OR
— 541-567 not yet reported which blocks → QWEST CORPORATION 9638 HERMISTON OR
— 541-574 not yet reported which blocks → QWEST CORPORATION 9638 NEWPORT OR
— 541-582 7XXX which blocks → QWEST CORPORATION 9638 ROGUERIVER OR
— 541-588 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9638 SISTERS OR
— 541-593 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-595 3XXX4XXX7XXX8XXX9XXX · 4 holders which blocks → QWEST CORPORATION 9638 BLACKBUTTE OR
— 541-598 3XXX4XXX5XXX6XXX · 2 holders which blocks → QWEST CORPORATION 9638 BEND OR
— 541-607 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE OR
— 541-608 not yet reported which blocks → QWEST CORPORATION 9638 MEDFORD OR
— 541-617 not yet reported which blocks → QWEST CORPORATION 9638 BEND OR
— 541-618 not yet reported which blocks → QWEST CORPORATION 9638 MEDFORD OR
— 541-664 not yet reported which blocks → QWEST CORPORATION 9638 CENTRAL PT OR
— 541-665 8XXX which blocks → QWEST CORPORATION 9638 CENTRAL PT OR
— 541-667 0XXX1XXX4XXX7XXX9XXX · 4 holders which blocks → QWEST CORPORATION 9638 HERMISTON OR
— 541-672 not yet reported which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-673 not yet reported which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-677 not yet reported which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-679 not yet reported which blocks → QWEST CORPORATION 9638 ROSEBURG OR
— 541-681 not yet reported which blocks → QWEST CORPORATION 9638 EUGENE 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.