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 650
PACIFIC BELL 273
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
— 650-347 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-348 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-349 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-350 0XXX2XXX4XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-354 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 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
— 650-361 not yet reported which blocks → PACIFIC BELL 9740 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
— 650-372 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
— 650-377 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
— 650-390 2XXX3XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-401 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-404 6XXX7XXX · 2 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-413 9XXX which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-424 none assigned yet which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-428 not yet reported which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-432 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-461 0XXX3XXX4XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-462 4XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-463 1XXX6XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-466 0–9 XXXall 10 · 3 holders which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-467 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-470 9XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-473 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-474 1XXX5XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-478 not yet reported which blocks → PACIFIC BELL 9740 SNFC CNTRL CA
— 650-482 7XXX8XXX · 2 holders which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-485 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-486 0XXX1XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-493 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-494 4XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-496 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-506 not yet reported which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-508 not yet reported which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-513 0XXX1XXX2XXX6XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-522 0XXX3XXX · 2 holders which blocks → PACIFIC BELL 9740 SAN MATEO 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.