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 586
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 132
MICHIGAN BELL TEL CO 100
NEW CINGULAR WIRELESS PCS, LLC - IL 60
OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 43
AMERICAN MESSAGING SERVICES, LLC 27
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
— 586-634 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 WARREN MI
— 586-646 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E NEW HAVEN MI
— 586-649 0XXX2XXX3XXX6XXX7XXX8XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 MT CLEMENS MI
— 586-662 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-663 2XXX4XXX5XXX6XXX8XXX9XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-665 3XXX4XXX7XXX8XXX9XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-668 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-675 0XXX1XXX2XXX · 2 holders which blocks → METROPCS, INC. 5562 ROSEVILLE MI
— 586-677 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 WASHINGTON MI
— 586-681 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 MT CLEMENS MI
— 586-684 1XXX3XXX4XXX5XXX6XXX9XXX · 6 holders which blocks → PAETEC ITEL, LLC 829J NEWBALTIMR MI
— 586-685 6XXX7XXX · 2 holders which blocks → PAETEC ITEL, LLC 829J UTICA MI
— 586-690 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-693 5XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 WARREN MI
— 586-697 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E WASHINGTON MI
— 586-698 2XXX7XXX8XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J WARREN MI
— 586-700 not yet reported which blocks → MI
— 586-703 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-704 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 MT CLEMENS MI
— 586-707 8XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-708 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 WARREN MI
— 586-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MI
— 586-713 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-716 6XXX which blocks → MICHIGAN BELL TEL CO 9323 NEWBALTIMR MI
— 586-717 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 WARREN MI
— 586-718 2XXX3XXX4XXX5XXX6XXX8XXX9XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-719 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-722 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 WARREN MI
— 586-723 1XXX2XXX3XXX4XXX5XXX6XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 MT CLEMENS MI
— 586-725 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 NEWBALTIMR MI
— 586-726 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 UTICA MI
— 586-727 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 RICHMOND MI
— 586-731 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 UTICA MI
— 586-734 not yet reported which blocks → MI
— 586-737 3XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J UTICA MI
— 586-738 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E MT CLEMENS MI
— 586-739 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 UTICA MI
— 586-741 1XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 MT CLEMENS MI
— 586-746 0XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → MICHIGAN BELL TEL CO 9323 MT CLEMENS MI
— 586-747 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-749 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 NEW HAVEN MI
— 586-751 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-752 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROMEO MI
— 586-753 5XXX6XXX7XXX which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-754 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-755 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-756 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-757 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-758 9XXX which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE MI
— 586-759 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 CENTERLINE 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.