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 231
NEW CINGULAR WIRELESS PCS, LLC - IL 72
MICHIGAN BELL TEL CO 72
FRONTIER NORTH, INC. - MI 52
ONVOY, LLCV - MI 49
TELNET WORLDWIDE, INC. 43
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
— 231-760 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-762 not yet reported which blocks → MICHIGAN CENTRAL BROADBAND COMPANY, LLC 785G AMBLE MI
— 231-766 1XXX6XXX7XXX8XXX · 3 holders which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-767 5XXX6XXX · 2 holders which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-768 0XXX1XXX2XXX3XXX6XXX7XXX8XXX · 5 holders which blocks → MICHIGAN BELL TEL CO 9323 LE ROY MI
— 231-769 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-773 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-775 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CADILLAC MI
— 231-777 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-779 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CADILLAC MI
— 231-780 7XXX8XXX which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-788 8XXX9XXX · 2 holders which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-793 3XXX6XXX · 2 holders which blocks → AT&T ENTERPRISES, LLC 516C WHITECLOUD MI
— 231-796 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 BIG RAPIDS MI
— 231-797 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → MICHIGAN BELL TEL CO 9323 LUTHER MI
— 231-798 5XXX which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-799 5XXX which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-810 not yet reported which blocks → MI
— 231-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MI
— 231-813 not yet reported which blocks → 123.NET, LLC 2550 LUDINGTON MI
— 231-818 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CHEBOYGAN MI
— 231-821 3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → FRONTIER NORTH, INC. - MI 0695 HOLTON MI
— 231-823 1XXX4XXX5XXX7XXX · 4 holders which blocks → FRONTIER NORTH, INC. - MI 0695 STANWOOD MI
— 231-824 0XXX1XXX2XXX4XXX5XXX7XXX8XXX · 6 holders which blocks → MICHIGAN BELL TEL CO 9323 MANTON MI
— 231-825 1XXX3XXX6XXX7XXX9XXX · 5 holders which blocks → MICHIGAN BELL TEL CO 9323 MCBAIN MI
— 231-826 6XXX which blocks → BRIGHTSPEED OF NORTHERN MICHIGAN, INC 0705 FALMOUTH MI
— 231-828 0XXX1XXX2XXX3XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER NORTH, INC. - MI 0695 TWIN LAKE MI
— 231-829 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → MICHIGAN BELL TEL CO 9323 TUSTIN MI
— 231-830 4XXX5XXX6XXX7XXX which blocks → FRONTIER NORTH, INC. - MI 0695 MUSKEGON MI
— 231-831 0XXX1XXX2XXX6XXX8XXX9XXX · 4 holders which blocks → ONVOY, LLCV - MI 543C EASTJORDAN MI
— 231-832 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 REED CITY MI
— 231-834 2XXX3XXX4XXX6XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 GRANT MI
— 231-837 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 FREMONT MI
— 231-839 not yet reported which blocks → BRIGHTSPEED OF MICHIGAN, LLC 0702 LAKE CITY MI
— 231-843 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 LUDINGTON MI
— 231-845 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 LUDINGTON MI
— 231-846 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 CADILLAC MI
— 231-848 not yet reported which blocks → KALEVA TEL. CO. 0703 WELLSTON MI
— 231-852 1XXX3XXX8XXX9XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LUDINGTON MI
— 231-853 1XXX3XXX4XXX7XXX9XXX · 4 holders which blocks → FRONTIER NORTH, INC. - MI 0695 RAVENNA MI
— 231-854 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 HESPERIA MI
— 231-855 4XXX5XXX6XXX7XXX8XXX9XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 MUSKEGON MI
— 231-856 2XXX3XXX6XXX8XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 MORLEY MI
— 231-859 not yet reported which blocks → KALEVA TEL. CO. 0703 DUBLIN MI
— 231-861 1XXX9XXX · 2 holders which blocks → FRONTIER NORTH, INC. - MI 0695 SHELBY MI
— 231-862 4XXX which blocks → ACE TEL. CO. OF MICHIGAN, INC. 0704 HOXEYVILLE MI
— 231-864 not yet reported which blocks → BRIGHTSPEED OF MICHIGAN, LLC 0702 BEAR LAKE MI
— 231-865 9XXX which blocks → FRONTIER NORTH, INC. - MI 0695 FRUITPORT MI
— 231-867 0XXX1XXX4XXX6XXX8XXX9XXX · 4 holders which blocks → BRIGHTSPEED OF CENTRAL MICHIGAN, INC 0671 CHIPPEWALK MI
— 231-869 1XXX3XXX · 2 holders which blocks → FRONTIER NORTH, INC. - MI 0695 PENTWATER MI

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.