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 548
Fibernetics Corporation 159
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
2021-08-26 548-277 not yet reported which blocks → Fibernetics Corporation 464D Port Rowan —
2021-08-26 548-278 not yet reported which blocks → Fibernetics Corporation 464D Waterford —
2021-07-29 548-268 not yet reported which blocks → Fibernetics Corporation 464D Arthur —
2021-07-29 548-269 not yet reported which blocks → Fibernetics Corporation 464D Dundalk —
2021-07-29 548-270 not yet reported which blocks → Fibernetics Corporation 464D Grand Valley —
2021-07-29 548-271 not yet reported which blocks → Fibernetics Corporation 464D Holstein —
2021-07-29 548-272 not yet reported which blocks → Fibernetics Corporation 464D Mount Forest —
2021-06-11 548-531 not yet reported which blocks → Fibernetics Corporation 464D Fingal —
2021-06-03 548-532 not yet reported which blocks → Fibernetics Corporation 464D Dutton —
2021-06-03 548-534 not yet reported which blocks → Fibernetics Corporation 464D Port Stanley —
2021-06-03 548-535 not yet reported which blocks → Fibernetics Corporation 464D Rodney —
2021-06-03 548-536 not yet reported which blocks → Fibernetics Corporation 464D Shedden —
2021-06-03 548-537 not yet reported which blocks → Fibernetics Corporation 464D Sparta —
2021-06-03 548-538 not yet reported which blocks → Fibernetics Corporation 464D St. Thomas —
2021-06-03 548-539 not yet reported which blocks → Fibernetics Corporation 464D West Lorne —
2021-01-06 548-257 not yet reported which blocks → Fibernetics Corporation 464D Comber —
2021-01-06 548-258 not yet reported which blocks → Fibernetics Corporation 464D Stoney Point —
2021-01-06 548-259 not yet reported which blocks → Fibernetics Corporation 464D Woodslee —
2021-01-06 548-260 not yet reported which blocks → Fibernetics Corporation 464D Emeryville —
2021-01-06 548-261 not yet reported which blocks → Fibernetics Corporation 464D Pleasant Park —
2021-01-06 548-262 not yet reported which blocks → Fibernetics Corporation 464D Harrow —
2021-01-06 548-263 not yet reported which blocks → Fibernetics Corporation 464D La Salle —
2021-01-06 548-264 not yet reported which blocks → Fibernetics Corporation 464D Maidstone —
2021-01-06 548-265 not yet reported which blocks → Fibernetics Corporation 464D McGregor —
2021-01-06 548-266 not yet reported which blocks → Fibernetics Corporation 464D Pelee Island —
2021-01-06 548-267 not yet reported which blocks → Fibernetics Corporation 464D Wheatley —
2020-12-11 548-249 not yet reported which blocks → Fibernetics Corporation 464D Belle River —
2020-12-03 548-240 not yet reported which blocks → Fibernetics Corporation 464D Melbourne —
2020-12-03 548-241 not yet reported which blocks → Fibernetics Corporation 464D Mount Brydges —
2020-12-03 548-242 not yet reported which blocks → Fibernetics Corporation 464D Wardsville —
2020-12-03 548-243 not yet reported which blocks → Fibernetics Corporation 464D Dorchester —
2020-12-03 548-244 not yet reported which blocks → Fibernetics Corporation 464D Harrietsville —
2020-12-03 548-245 not yet reported which blocks → Fibernetics Corporation 464D Thorndale —
2020-12-03 548-246 not yet reported which blocks → Fibernetics Corporation 464D Ilderton —
2020-12-03 548-247 not yet reported which blocks → Fibernetics Corporation 464D Kerwood —
2020-12-02 548-239 not yet reported which blocks → Fibernetics Corporation 464D Belmont —
2020-12-01 548-234 not yet reported which blocks → Fibernetics Corporation 464D Ailsa Craig —
2020-12-01 548-235 not yet reported which blocks → Fibernetics Corporation 464D Centralia —
2020-12-01 548-236 not yet reported which blocks → Fibernetics Corporation 464D Crediton —
2020-12-01 548-237 not yet reported which blocks → Fibernetics Corporation 464D Lucan —
2020-12-01 548-238 not yet reported which blocks → Fibernetics Corporation 464D Nairn —
2020-11-27 548-570 not yet reported which blocks → Fibernetics Corporation 464D Blyth —
2020-11-27 548-571 not yet reported which blocks → Fibernetics Corporation 464D Brussels —
2020-11-27 548-572 not yet reported which blocks → Fibernetics Corporation 464D Hensall —
2020-11-27 548-573 not yet reported which blocks → Fibernetics Corporation 464D Lucknow —
2020-11-27 548-574 not yet reported which blocks → Fibernetics Corporation 464D Seaforth —
2020-11-27 548-575 not yet reported which blocks → Fibernetics Corporation 464D Wingham —
2020-11-26 548-569 not yet reported which blocks → Fibernetics Corporation 464D Auburn —
2020-11-25 548-559 not yet reported which blocks → Fibernetics Corporation 464D Simcoe —
2020-11-25 548-560 not yet reported which blocks → Fibernetics Corporation 464D Stratford —

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.