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
2010-12-23 650-308 0–9 XXXall 10 · 5 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
2001-01-25 650-995 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-210 4XXX6XXX7XXX · 3 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-212 5XXX6XXX · 2 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-213 2XXX6XXX7XXX · 3 holders which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-216 5XXX7XXX8XXX · 3 holders which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-225 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-233 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-234 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-236 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-237 9XXX which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-244 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-246 0XXX9XXX which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-251 4XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-254 3XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-259 none assigned yet which blocks → PACIFIC BELL 9740 MILLBRAE CA
— 650-261 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-266 not yet reported which blocks → PACIFIC BELL 9740 SSNFRNCSCO CA
— 650-286 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-287 5XXX which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-289 8XXX which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-293 0XXX1XXX2XXX3XXX4XXX7XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-294 0XXX3XXX4XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-295 0XXX1XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-298 1XXX2XXX which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-299 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-301 not yet reported which blocks → PACIFIC BELL 9740 SNFC JUNPR CA
— 650-306 not yet reported which blocks → PACIFIC BELL 9740 REDWOOD CY CA
— 650-312 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-314 1XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-318 1XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-320 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-321 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-322 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-323 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-324 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-325 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-326 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-327 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-328 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-329 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-330 not yet reported which blocks → PACIFIC BELL 9740 PALO ALTO CA
— 650-335 5XXX8XXX · 2 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-336 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → PACIFIC BELL 9740 MT VIEW CA
— 650-340 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-341 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-342 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-343 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-344 not yet reported which blocks → PACIFIC BELL 9740 SAN MATEO CA
— 650-345 not yet reported 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.