NumberResearch Membership · Data 09/23/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/23/2026

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 343
Fibernetics Corporation 92
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
2021-12-13 343-863 not yet reported which blocks → Fibernetics Corporation 464D Northbrook —
2021-12-13 343-864 not yet reported which blocks → Fibernetics Corporation 464D Thurlow —
2021-12-13 343-865 not yet reported which blocks → Fibernetics Corporation 464D Wellington —
2021-12-13 343-866 not yet reported which blocks → Fibernetics Corporation 464D Wooler —
2020-10-15 343-464 not yet reported which blocks → Fibernetics Corporation 464D Almonte —
2020-10-15 343-465 not yet reported which blocks → Fibernetics Corporation 464D Jockvale —
2020-10-15 343-466 not yet reported which blocks → Fibernetics Corporation 464D North Gower —
2020-10-15 343-467 not yet reported which blocks → Fibernetics Corporation 464D Osgoode —
2020-10-15 343-491 not yet reported which blocks → Fibernetics Corporation 464D Carp —
2020-10-15 343-492 not yet reported which blocks → Fibernetics Corporation 464D Constance Bay —
2020-10-15 343-493 not yet reported which blocks → Fibernetics Corporation 464D Pakenham —
2020-10-15 343-895 not yet reported which blocks → Fibernetics Corporation 464D Casselman —
2020-10-15 343-896 not yet reported which blocks → Fibernetics Corporation 464D Merrickville —
2020-10-15 343-897 not yet reported which blocks → Fibernetics Corporation 464D Russell —
2020-10-15 343-898 not yet reported which blocks → Fibernetics Corporation 464D Winchester —
2020-10-14 343-454 not yet reported which blocks → Fibernetics Corporation 464D Alfred —
2020-10-14 343-455 not yet reported which blocks → Fibernetics Corporation 464D Clarence Creek —
2020-10-14 343-456 not yet reported which blocks → Fibernetics Corporation 464D Embrun —
2020-10-14 343-457 not yet reported which blocks → Fibernetics Corporation 464D Plantagenet —
2020-10-14 343-458 not yet reported which blocks → Fibernetics Corporation 464D Rockland —
2020-09-11 343-894 not yet reported which blocks → Fibernetics Corporation 464D Sydenham —
2020-09-10 343-892 not yet reported which blocks → Fibernetics Corporation 464D Bath —
2020-09-10 343-893 not yet reported which blocks → Fibernetics Corporation 464D Napanee —
2020-09-09 343-638 not yet reported which blocks → Fibernetics Corporation 464D Frankford —
2020-09-09 343-639 not yet reported which blocks → Fibernetics Corporation 464D Marmora —
2020-09-09 343-640 not yet reported which blocks → Fibernetics Corporation 464D Plevna —
2020-09-09 343-641 not yet reported which blocks → Fibernetics Corporation 464D Stirling —
2020-09-09 343-642 not yet reported which blocks → Fibernetics Corporation 464D Tweed —
2020-06-09 343-643 not yet reported which blocks → Fibernetics Corporation 464D Brockville —
2020-05-13 343-347 not yet reported which blocks → Fibernetics Corporation 464D Arnprior —
2020-05-13 343-348 not yet reported which blocks → Fibernetics Corporation 464D Cumberland —
2020-05-13 343-349 not yet reported which blocks → Fibernetics Corporation 464D Gloucester —
2020-05-13 343-350 not yet reported which blocks → Fibernetics Corporation 464D Orleans —
2020-05-13 343-351 not yet reported which blocks → Fibernetics Corporation 464D Richmond —
2020-04-24 343-293 not yet reported which blocks → Fibernetics Corporation 464D Kingston —
2015-09-25 343-881 not yet reported which blocks → Fibernetics Corporation 464D Smiths Falls —
2013-01-07 343-887 not yet reported which blocks → Fibernetics Corporation 464D Ottawa-Hull —
2012-11-19 343-885 not yet reported which blocks → Fibernetics Corporation 464D Cornwall —
2012-11-19 343-886 not yet reported which blocks → Fibernetics Corporation 464D Vankleek Hill —
2012-03-22 343-884 not yet reported which blocks → Fibernetics Corporation 464D Kingston —
2012-03-20 343-882 not yet reported which blocks → Fibernetics Corporation 464D Ottawa-Hull —
2009-11-20 343-883 not yet reported which blocks → Fibernetics Corporation 464D Ottawa-Hull —

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/23/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.