NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026

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 918
SOUTHWESTERN BELL 236
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
— 918-330 0XXX1XXX2XXX3XXX6XXX7XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-331 none assigned yet which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-332 0XXX1XXX2XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-333 not yet reported which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-335 not yet reported which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-336 not yet reported which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-337 not yet reported which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-338 6XXX which blocks → SOUTHWESTERN BELL 9533 BARTLESVL OK
— 918-341 not yet reported which blocks → SOUTHWESTERN BELL 9533 CLAREMORE OK
— 918-342 not yet reported which blocks → SOUTHWESTERN BELL 9533 CLAREMORE OK
— 918-343 2XXX which blocks → SOUTHWESTERN BELL 9533 CLAREMORE OK
— 918-352 5XXX6XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 DRUMRIGHT OK
— 918-358 0XXX4XXX6XXX7XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 CLEVELAND OK
— 918-367 0XXX7XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 BRISTOW OK
— 918-371 not yet reported which blocks → SOUTHWESTERN BELL 9533 COLLINSVL OK
— 918-372 0XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 RIPLEY OK
— 918-376 0XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 OWASSO OK
— 918-379 2XXX3XXX4XXX5XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 CATOOSA OK
— 918-382 8XXX which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-383 0XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 NEW HOME OK
— 918-384 8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-387 0XXX3XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 YALE OK
— 918-396 8XXX which blocks → SOUTHWESTERN BELL 9533 SKIATOOK OK
— 918-420 1XXX2XXX3XXX4XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 MCALESTER OK
— 918-421 none assigned yet which blocks → SOUTHWESTERN BELL 9533 MCALESTER OK
— 918-423 not yet reported which blocks → SOUTHWESTERN BELL 9533 MCALESTER OK
— 918-425 8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-426 8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 MCALESTER OK
— 918-427 not yet reported which blocks → SOUTHWESTERN BELL 9533 MULDROW OK
— 918-428 1XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-429 6XXX which blocks → SOUTHWESTERN BELL 9533 MCALESTER OK
— 918-430 3XXX4XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-431 not yet reported which blocks → SOUTHWESTERN BELL 9533 TAHLEQUAH OK
— 918-436 3XXX4XXX5XXX6XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 POCOLA OK
— 918-437 6XXX which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-438 4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-439 6XXX which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-443 0XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 CLAREMORE OK
— 918-445 not yet reported which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-446 not yet reported which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-447 1XXX which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-450 not yet reported which blocks → SOUTHWESTERN BELL 9533 TAHLEQUAH OK
— 918-453 3XXX6XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 TAHLEQUAH OK
— 918-456 not yet reported which blocks → SOUTHWESTERN BELL 9533 TAHLEQUAH OK
— 918-457 0XXX6XXX7XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 TAHLEQUAH OK
— 918-458 not yet reported which blocks → SOUTHWESTERN BELL 9533 TAHLEQUAH OK
— 918-460 not yet reported which blocks → SOUTHWESTERN BELL 9533 TULSA OK
— 918-465 none assigned yet which blocks → SOUTHWESTERN BELL 9533 WILBURTON OK
— 918-467 1XXX2XXX5XXX7XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 DELAWARE OK
— 918-475 0XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 ALLUWE OK

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.