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
— 586-764 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 MT CLEMENS MI
— 586-770 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 MT CLEMENS MI
— 586-771 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-772 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-773 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-774 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-775 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-776 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-777 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-778 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-779 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROSEVILLE MI
— 586-781 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 WASHINGTON MI
— 586-782 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 CENTERLINE MI
— 586-783 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 MT CLEMENS MI
— 586-784 0XXX1XXX3XXX6XXX7XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 ARMADA MI
— 586-786 2XXX3XXX4XXX8XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 WASHINGTON MI
— 586-790 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 MT CLEMENS MI
— 586-791 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 MT CLEMENS MI
— 586-792 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 MT CLEMENS MI
— 586-795 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 WARREN MI
— 586-799 2XXX3XXX4XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 UTICA MI
— 586-801 1XXX2XXX · 2 holders which blocks → METROPCS, INC. 5562 ROSEVILLE MI
— 586-802 0XXX2XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 UTICA MI
— 586-803 3XXX4XXX7XXX8XXX · 3 holders which blocks → MICHIGAN BELL TEL CO 9323 UTICA MI
— 586-804 0–9 XXXall 10 · 2 holders which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 WARREN MI
— 586-805 6XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-806 5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → WOW! INTERNET, CABLE AND PHONE 961J CENTERLINE MI
— 586-808 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 WARREN MI
— 586-810 not yet reported which blocks → MI
— 586-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MI
— 586-816 9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 WASHINGTON MI
— 586-817 5XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-819 1XXX3XXX4XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 WARREN MI
— 586-823 2XXX which blocks → METROPCS, INC. 5562 ROSEVILLE MI
— 586-825 3XXX9XXX · 2 holders which blocks → MICHIGAN BELL TEL CO 9323 WARREN MI
— 586-826 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 WARREN MI
— 586-830 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 WARREN MI
— 586-831 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 WARREN MI
— 586-832 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 WARREN MI
— 586-834 0XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E CENTERLINE MI
— 586-838 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 WARREN MI
— 586-839 4XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-840 4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E MT CLEMENS MI
— 586-843 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E UTICA MI
— 586-846 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-850 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-854 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 MT CLEMENS MI
— 586-856 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 UTICA MI
— 586-859 0XXX1XXX3XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E ROSEVILLE MI
— 586-860 not yet reported which blocks → SPOK, INC. 6630 WARREN 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.