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 231
123.NET, LLC 34
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
2003-03-25 231-220 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → 123.NET, LLC 2550 MUSKEGON MI
2002-08-27 231-440 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → 123.NET, LLC 2550 BALDWIN MI
2002-08-27 231-441 not yet reported which blocks → 123.NET, LLC 2550 FIFE LAKE MI
2002-08-27 231-488 not yet reported which blocks → 123.NET, LLC 2550 MANISTEE MI
2002-08-27 231-520 not yet reported which blocks → 123.NET, LLC 2550 CHARLEVOIX MI
2002-08-27 231-538 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → 123.NET, LLC 2550 FREMONT MI
2002-08-27 231-583 none assigned yet which blocks → 123.NET, LLC 2550 LUDINGTON MI
2002-08-27 231-635 not yet reported which blocks → 123.NET, LLC 2550 MACKINAWCY MI
2002-08-27 231-639 not yet reported which blocks → 123.NET, LLC 2550 BEULAH MI
2002-08-27 231-643 1XXX2XXX3XXX4XXX6XXX which blocks → 123.NET, LLC 2550 MORLEY MI
2002-08-27 231-656 not yet reported which blocks → 123.NET, LLC 2550 KALKASKA MI
2002-08-27 231-660 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → 123.NET, LLC 2550 BIG RAPIDS MI
2002-08-27 231-686 not yet reported which blocks → 123.NET, LLC 2550 FRANKFORT MI
2002-08-27 231-721 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → 123.NET, LLC 2550 HART MI
2002-08-27 231-776 not yet reported which blocks → 123.NET, LLC 2550 PETOSKEY MI
2002-08-27 231-778 not yet reported which blocks → 123.NET, LLC 2550 TRAVERSECY MI
2002-08-27 231-782 not yet reported which blocks → 123.NET, LLC 2550 CHEBOYGAN MI
2002-08-27 231-792 not yet reported which blocks → 123.NET, LLC 2550 MANCELONA MI
2002-08-27 231-806 not yet reported which blocks → 123.NET, LLC 2550 CORAL MI
2002-08-27 231-836 not yet reported which blocks → 123.NET, LLC 2550 EVART MI
2002-08-27 231-842 not yet reported which blocks → 123.NET, LLC 2550 CADILLAC MI
2002-08-27 231-874 not yet reported which blocks → 123.NET, LLC 2550 WOLVERINE MI
2002-08-27 231-899 not yet reported which blocks → 123.NET, LLC 2550 NORTHPORT MI
2002-08-27 231-908 not yet reported which blocks → 123.NET, LLC 2550 MCBAIN MI
2002-08-27 231-925 5XXX7XXX · 2 holders which blocks → 123.NET, LLC 2550 SCOTTVILLE MI
2002-08-27 231-974 1XXX2XXX3XXX4XXX6XXX · 4 holders which blocks → 123.NET, LLC 2550 GRANT MI
2002-08-12 231-636 1XXX2XXX3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → 123.NET, LLC 2550 HOWARDCITY MI
2002-08-12 231-808 not yet reported which blocks → 123.NET, LLC 2550 CENTRAL LK MI
— 231-522 not yet reported which blocks → 123.NET, LLC 2550 LUTHER MI
— 231-568 not yet reported which blocks → 123.NET, LLC 2550 TRAVERSECY MI
— 231-614 not yet reported which blocks → 123.NET, LLC 2550 PENTWATER MI
— 231-731 not yet reported which blocks → 123.NET, LLC 2550 SHELBY MI
— 231-813 not yet reported which blocks → 123.NET, LLC 2550 LUDINGTON MI
— 231-877 not yet reported which blocks → 123.NET, LLC 2550 NORTHPORT MI

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.