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 909
FRONTIER CALIFORNIA INC. 156
T-MOBILE USA, INC. 87
NEW CINGULAR WIRELESS PCS, LLC 75
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 72
METROPCS NETWORKS, LLC 52
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
— 909-292 3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J ONTARIO CA
— 909-297 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 UPLAND CA
— 909-299 not yet reported which blocks → SPOK, INC. 6630 CORONA CA
— 909-300 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C S BERNDINO CA
— 909-303 0–9 XXXall 10 · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 UPLAND CA
— 909-305 3XXX which blocks → FRONTIER CALIFORNIA INC. 2319 CLAREMONT CA
— 909-307 4XXX which blocks → FRONTIER CALIFORNIA INC. 2319 REDLANDS CA
— 909-309 not yet reported which blocks → SPOK, INC. 6630 ONTARIO CA
— 909-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CA
— 909-321 0–9 XXXall 10 · 6 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J ONTARIO CA
— 909-322 none assigned yet which blocks → METROPCS NETWORKS, LLC 899D ONTARIO CA
— 909-331 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ONTARIO CA
— 909-333 0–9 XXXall 10 · 6 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E FONTANA CA
— 909-335 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 REDLANDS CA
— 909-336 8XXX which blocks → FRONTIER CALIFORNIA INC. 2319 ARROWHEAD CA
— 909-337 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 ARROWHEAD CA
— 909-338 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 CRESTLINE CA
— 909-339 not yet reported which blocks → 33 WIRELESS INC. 6967 RIVERSIDE CA
— 909-348 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 DIAMONDBAR CA
— 909-349 4XXX5XXX7XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 FONTANA CA
— 909-350 not yet reported which blocks → PACIFIC BELL 9740 FONTANA CA
— 909-355 not yet reported which blocks → PACIFIC BELL 9740 FONTANA CA
— 909-356 not yet reported which blocks → PACIFIC BELL 9740 FONTANA CA
— 909-357 not yet reported which blocks → PACIFIC BELL 9740 FONTANA CA
— 909-358 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - CA 649C ARROWHEAD CA
— 909-359 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E HIGHLAND CA
— 909-362 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 HIGHLAND CA
— 909-363 4XXX5XXX6XXX · 2 holders which blocks → MATRIX TELECOM, LLC. S/I/I TNCI - CA 7379 REDLANDS CA
— 909-364 none assigned yet which blocks → FRONTIER CALIFORNIA INC. 2319 CHINO CA
— 909-366 0XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 BIGBEAR LK CA
— 909-370 not yet reported which blocks → PACIFIC BELL 9740 COLTON CA
— 909-373 4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J UPLAND CA
— 909-376 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ONTARIO CA
— 909-379 2XXX3XXX4XXX5XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 7718 S BERNDINO CA
— 909-380 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-381 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-382 1XXX8XXX9XXX · 3 holders which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-383 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-384 2XXX which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-385 not yet reported which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E S BERNDINO CA
— 909-386 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-387 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-388 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 S BERNDINO CA
— 909-389 5XXX6XXX8XXX · 3 holders which blocks → FRONTIER CALIFORNIA INC. 2319 MENTONE CA
— 909-390 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 ONTARIO CA
— 909-391 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 ONTARIO CA
— 909-392 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 CLAREMONT CA
— 909-393 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 CHINO CA
— 909-394 not yet reported which blocks → FRONTIER CALIFORNIA INC. 2319 CLAREMONT CA
— 909-395 6XXX7XXX which blocks → FRONTIER CALIFORNIA INC. 2319 ONTARIO 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.