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
— 650-610 1XXX2XXX7XXX which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-612 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-614 1XXX5XXX · 2 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-615 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-616 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-617 5XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-620 0XXX1XXX4XXX7XXX8XXX · 3 holders which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-621 0XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-622 2XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-623 2XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-624 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-625 7XXX which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-627 3XXX4XXX6XXX7XXX · 4 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-631 not yet reported which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-632 5XXX7XXX8XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-633 not yet reported which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-634 8XXX which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-635 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-637 not yet reported which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-638 8XXX which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-652 8XXX which blocks → PACIFIC BELL 9740 MILLBRAE CA
— 650-654 8XXX which blocks → PACIFIC BELL 9740 SNCRL-BLMT CA
— 650-655 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-685 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-688 5XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-691 3XXX5XXX8XXX · 2 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-692 not yet reported which blocks → PACIFIC BELL 9740 MILLBRAE CA
— 650-694 8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-696 0XXX which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-697 not yet reported which blocks → PACIFIC BELL 9740 MILLBRAE CA
— 650-701 3XXX4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-712 not yet reported which blocks → PACIFIC BELL 9740 HALFMOONBY CA
— 650-726 not yet reported which blocks → PACIFIC BELL 9740 HALFMOONBY CA
— 650-728 4XXX6XXX · 2 holders which blocks → PACIFIC BELL 9740 MOSS BEACH CA
— 650-737 2XXX4XXX · 2 holders which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-738 not yet reported which blocks → PACIFIC BELL 9740 PACIFICA CA
— 650-739 2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-741 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-742 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-746 3XXX4XXX5XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-747 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → PACIFIC BELL 9740 LA HONDA CA
— 650-752 1XXX4XXX6XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-754 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-755 not yet reported which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-756 not yet reported which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-757 not yet reported which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-758 0XXX7XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-761 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-762 4XXX5XXX6XXX8XXX9XXX · 2 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-777 1XXX2XXX3XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → PACIFIC BELL 9740 MILLBRAE 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.