NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

2 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, last 30 days — NPA 661
ONVOY, LLC - CA 2
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
— 661-777 0XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 LEBEC CA
— 661-778 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 DELANO CA
— 661-779 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 ARVIN CA
— 661-780 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → ONVOY, LLC - CA 649C PLDL LNVY CA
— 661-789 7XXX8XXX · 2 holders which blocks → PACIFIC BELL 9740 PLDL PLDL CA
— 661-791 not yet reported which blocks → UTILITY TELECOM GROUP, LLC - CA 9262 PLDL PLDL CA
— 661-792 4XXX7XXX8XXX · 2 holders which blocks → FRONTIER CALIFORNIA INC. 4420 MCFARLAND CA
— 661-793 2XXX3XXX8XXX9XXX · 2 holders which blocks → ONVOY, LLC - CA 649C PLDL LNVY CA
— 661-797 0XXX1XXX3XXX4XXX5XXX · 3 holders which blocks → FRONTIER CALIFORNIA INC. 4420 LOST HILLS CA
— 661-799 not yet reported which blocks → PACIFIC BELL 9740 SNCA NHCS CA
— 661-800 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 BKFD MAIN CA
— 661-802 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7139 LANCASTER CA
— 661-805 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 BKFD SOUTH CA
— 661-808 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-809 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 BKFD SOUTH CA
— 661-810 none assigned yet which blocks → METROPCS NETWORKS, LLC 899D PLDL PLDL CA
— 661-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CA
— 661-816 none assigned yet which blocks → T-MOBILE USA, INC. 6529 PLDL PLDL CA
— 661-817 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-818 not yet reported which blocks → CA
— 661-821 8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 TEHACHAPI CA
— 661-822 not yet reported which blocks → PACIFIC BELL 9740 TEHACHAPI CA
— 661-823 4XXX which blocks → PACIFIC BELL 9740 TEHACHAPI CA
— 661-824 not yet reported which blocks → PACIFIC BELL 9740 MOJAVE CA
— 661-825 4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 TEHACHAPI CA
— 661-827 2XXX6XXX7XXX · 3 holders which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-831 not yet reported which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-832 not yet reported which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-833 not yet reported which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-834 not yet reported which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-835 6XXX which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-836 5XXX7XXX · 2 holders which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-837 not yet reported which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-839 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7139 PLDL PLDL CA
— 661-840 0XXX1XXX2XXX3XXX4XXX7XXX · 2 holders which blocks → ONVOY SPECTRUM, LLC 624H BKFD MAIN CA
— 661-842 not yet reported which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-843 0XXX4XXX7XXX8XXX · 4 holders which blocks → ONVOY, LLC - CA 649C BKFD MAIN CA
— 661-845 not yet reported which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-846 0XXX2XXX · 2 holders which blocks → ONVOY, LLC - CA 649C BKFD MAIN CA
— 661-849 0XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 EARLIMART CA
— 661-851 0XXX2XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 EARLIMART CA
— 661-852 1XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-854 9XXX which blocks → PACIFIC BELL 9740 ARVIN CA
— 661-855 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 ARVIN CA
— 661-857 2XXX4XXX5XXX7XXX8XXX · 5 holders which blocks → METROPCS NETWORKS, LLC 899D SNCA NHCS CA
— 661-858 3XXX4XXX6XXX7XXX8XXX9XXX which blocks → PACIFIC BELL 9740 BKFD SOUTH CA
— 661-859 3XXX4XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-861 3XXX which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-862 0XXX1XXX2XXX3XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 BKFD MAIN CA
— 661-863 1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 BKFD MAIN CA

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.