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 650
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
— 650-355 not yet reported which blocks → PACIFIC BELL 9740 PACIFICA CA
— 650-356 8XXX which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-357 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-358 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-359 not yet reported which blocks → PACIFIC BELL 9740 PACIFICA CA
— 650-360 not yet reported which blocks → ONVOY, LLC - CA 649C SSNFRNCSCO CA
— 650-361 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-362 3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 REDWOOD CY CA
— 650-363 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-364 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-365 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-366 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-367 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-368 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-369 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-371 not yet reported which blocks → SPOK, INC. 6630 SAN MATEO CA
— 650-372 5XXX8XXX · 2 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-373 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-375 2XXX which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-376 0XXX3XXX7XXX8XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 SAN MATEO CA
— 650-377 none assigned yet which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-378 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-381 0XXX1XXX4XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-383 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 LOS ALTOS CA
— 650-384 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 PALO ALTO CA
— 650-385 1XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 REDWOOD CY CA
— 650-386 0XXX1XXX7XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 MT VIEW CA
— 650-387 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PALO ALTO CA
— 650-388 0XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 PALO ALTO CA
— 650-389 1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SAN MATEO CA
— 650-390 2XXX3XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-391 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 PALO ALTO CA
— 650-392 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 SSNFRNCSCO CA
— 650-393 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 SAN MATEO CA
— 650-394 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 SNCRL-BLMT CA
— 650-395 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 REDWOOD CY CA
— 650-396 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → T-MOBILE USA, INC. 6529 MT VIEW CA
— 650-397 0–9 XXXall 10 · 7 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E LOS ALTOS CA
— 650-399 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → ONVOY, LLC - CA 649C REDWOOD CY CA
— 650-400 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 REDWOOD CY CA
— 650-401 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-403 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SAN MATEO CA
— 650-404 6XXX7XXX · 2 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-406 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 6906 MT VIEW CA
— 650-409 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J MILLBRAE CA
— 650-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CA
— 650-412 5XXX6XXX7XXX8XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SNCRL-BLMT CA
— 650-413 9XXX which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-416 0XXX1XXX4XXX6XXX8XXX9XXX · 3 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J SSNFRNCSCO CA
— 650-417 1XXX3XXX4XXX5XXX8XXX9XXX · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J MT VIEW 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.