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 323
PACIFIC BELL 265
METROPCS NETWORKS, LLC 85
T-MOBILE USA, INC. 64
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 45
NEW CINGULAR WIRELESS PCS, LLC 39
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
— 323-393 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → IP HORIZON LLC 515J LSAN DA 09 CA
— 323-394 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 LSAN DA 14 CA
— 323-395 1XXX3XXX4XXX6XXX7XXX8XXX9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 LSAN DA 06 CA
— 323-400 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 MONTEBELLO CA
— 323-402 0–9 XXXall 10 · 6 holders which blocks → METROPCS NETWORKS, LLC 899D LSAN DA 11 CA
— 323-403 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 LSAN DA 12 CA
— 323-410 8XXX which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E LSAN DA 02 CA
— 323-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CA
— 323-414 not yet reported which blocks → SPOK, INC. 6630 LSAN DA 03 CA
— 323-415 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 05 CA
— 323-417 not yet reported which blocks → ONVOY, LLC - CA 649C LSAN DA 06 CA
— 323-418 2XXX7XXX · 2 holders which blocks → PACIFIC BELL 9740 LSAN DA 09 CA
— 323-419 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 LSAN DA 11 CA
— 323-420 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 LSAN DA 09 CA
— 323-421 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PACIFIC BELL 9740 LSAN DA 12 CA
— 323-422 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 LSAN DA 14 CA
— 323-423 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 LSAN DA 03 CA
— 323-424 0–9 XXXall 10 · 3 holders which blocks → AT&T ENTERPRISES, LLC 516C LSAN DA 13 CA
— 323-428 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 LSAN DA 14 CA
— 323-429 not yet reported which blocks → 33 WIRELESS INC. 6967 LSAN DA 14 CA
— 323-431 0XXX1XXX2XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 LSAN DA 12 CA
— 323-432 0XXX1XXX2XXX6XXX7XXX8XXX · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J LSAN DA 08 CA
— 323-433 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - CA 649C LSAN DA 13 CA
— 323-436 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-440 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 MONTEBELLO CA
— 323-441 3XXX5XXX6XXX · 2 holders which blocks → PACIFIC BELL 9740 LSAN DA 04 CA
— 323-442 0XXX which blocks → FRONTIER CALIFORNIA INC. 7534 LSAN DA 04 CA
— 323-443 4XXX5XXX which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E LSAN DA 03 CA
— 323-444 0XXX1XXX2XXX3XXX which blocks → UTILITY TELECOM GROUP, LLC - CA 9262 LSAN DA 06 CA
— 323-446 1XXX2XXX5XXX6XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 LSAN DA 05 CA
— 323-448 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 LSAN DA 09 CA
— 323-449 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 LSAN DA 14 CA
— 323-450 2XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J LSAN DA 14 CA
— 323-451 1XXX2XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J LSAN DA 09 CA
— 323-454 0XXX1XXX2XXX3XXX5XXX7XXX8XXX · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J LSAN DA 02 CA
— 323-456 0XXX2XXX3XXX4XXX5XXX6XXX9XXX · 5 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J LSAN DA 13 CA
— 323-459 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 LSAN DA 14 CA
— 323-460 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-461 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-462 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-463 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-464 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-465 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-466 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-467 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-468 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-469 not yet reported which blocks → PACIFIC BELL 9740 LSAN DA 14 CA
— 323-471 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - CA 649C LSAN DA 14 CA
— 323-472 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 LSAN DA 14 CA
— 323-473 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 LSAN DA 02 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.