NumberResearch Membership · Data 09/30/2026

Recent prefix assignments

372 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/30/2026

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, last 30 days
Rogers Communications Canada Inc. (Wireless) 46
8X8, INC. 43
NEW CINGULAR WIRELESS PCS, LLC - DC 27
NEW CINGULAR WIRELESS PCS, LLC - IL 23
ONVOY, LLC - CA 19
New assignments by month Oct 2026 Sep 2026 Aug 2026 Jul 2026 Jun 2026 May 2026 Apr 2026 Mar 2026 Feb 2026 Jan 2026 Dec 2025 Nov 2025
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Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 517-851 1XXX2XXX3XXX · 3 holders which blocks → FRONTIER MIDSTATES, INC. - MI 0681 STOCKBDG MI
— 517-852 3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 NASHVILLE MI
— 517-853 2XXX4XXX5XXX7XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 LANSING MI
— 517-857 not yet reported which blocks → SPRINGPORT TEL. CO. 0728 SPRINGPORT MI
— 517-868 0–9 XXXwhole prefix which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 DIMONDALE MI
— 517-869 not yet reported which blocks → FRONTIER COMMUNICATIONS OF MICHIGAN, INC. 4417 ALLEN MI
— 517-880 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 XXXXXXXXXX MI
— 517-881 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-882 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LANSING MI
— 517-884 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LANSING MI
— 517-885 0XXX1XXX2XXX3XXX5XXX8XXX · 3 holders which blocks → MICHIGAN BELL TEL CO 9323 LANSING MI
— 517-886 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LANSING MI
— 517-887 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LANSING MI
— 517-896 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-897 7XXX8XXX9XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-898 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-899 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-902 0XXX2XXX · 2 holders which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 ADRIAN MI
— 517-908 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 LANSING MI
— 517-911 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MI
— 517-913 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J LANSING MI
— 517-914 8XXX which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 JACKSON MI
— 517-917 0–9 XXXall 10 · 3 holders which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 JACKSON MI
— 517-918 4XXX5XXX7XXX8XXX which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 ADRIAN MI
— 517-919 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LAINGSBURG MI
— 517-927 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-930 8XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 LANSING MI
— 517-931 not yet reported which blocks → BANDWIDTH.COM CLEC, LLC - MI 991E TEKONSHA MI
— 517-933 not yet reported which blocks → ACD TELECOM, INC. - MI 3535 COLDWATER MI
— 517-936 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 JACKSON MI
— 517-937 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 JACKSON MI
— 517-944 3XXX8XXX which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 LANSING MI
— 517-945 1XXX2XXX3XXX4XXX6XXX8XXX9XXX · 2 holders which blocks → PAETEC ITEL, LLC 829J JACKSON MI
— 517-947 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J HOWELL MI
— 517-950 not yet reported which blocks → MI
— 517-955 0XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → ONVOY, LLCV - MI 543C DANSVILLE MI
— 517-957 not yet reported which blocks → ACD TELECOM, INC. - MI 3535 ONONDAGA MI
— 517-958 not yet reported which blocks → MI
— 517-959 not yet reported which blocks → MI
— 517-973 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 CHARLOTTE MI
— 517-974 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LANSING MI
— 517-976 not yet reported which blocks → MI
— 517-988 not yet reported which blocks → MI
— 517-989 not yet reported which blocks → MI
— 517-990 2XXX4XXX5XXX7XXX8XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 JACKSON MI
— 517-993 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E LANSING MI
— 517-994 0XXX1XXX5XXX6XXX8XXX · 4 holders which blocks → ACD TELECOM, INC. - MI 3535 PORTLAND MI
— 517-997 0XXX1XXX2XXX5XXX6XXX8XXX · 3 holders which blocks → ACD TELECOM, INC. - MI 3535 CHARLOTTE MI
— 517-998 not yet reported which blocks → ACD TELECOM, INC. - MI 3535 JACKSON MI
— 517-999 not yet reported which blocks → ACD TELECOM, INC. - MI 3535 LANSING MI

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/30/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.