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 206
QWEST CORPORATION 243
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
— 206-417 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-418 6XXX8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-421 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-431 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-433 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-439 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-440 6XXX which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-441 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-442 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-443 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-444 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-447 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-448 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-449 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-461 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-464 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-467 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-469 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-470 9XXX which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-490 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-500 0–9 XXXwhole prefix which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-504 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-506 0XXX1XXX2XXX4XXX · 4 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-509 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-515 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-516 1XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-517 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-520 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-521 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-522 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-523 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-524 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-525 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-526 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-527 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-528 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-529 3XXX4XXX5XXX7XXX · 3 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-544 none assigned yet which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-545 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-547 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-548 4XXX6XXX · 2 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-553 9XXX which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-554 1XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-568 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-574 8XXX which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-575 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-583 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-585 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-587 not yet reported which blocks → QWEST CORPORATION 9638 SEATTLE WA
— 206-592 2XXX3XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → QWEST CORPORATION 9638 DES MOINES 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.