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 405
SOUTHWESTERN BELL 237
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
— 405-489 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 CEMENT OK
— 405-491 3XXX4XXX5XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BETHANY OK
— 405-495 not yet reported which blocks → SOUTHWESTERN BELL 9533 BETHANY OK
— 405-498 2XXX3XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 BETHANY OK
— 405-499 not yet reported which blocks → SOUTHWESTERN BELL 9533 BETHANY OK
— 405-521 7XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-523 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-524 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-525 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-528 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-530 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-547 0XXX3XXX4XXX6XXX7XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 PERKINS OK
— 405-551 0XXX1XXX3XXX4XXX5XXX7XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-552 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-553 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-556 0XXX1XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-557 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-558 1XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-573 not yet reported which blocks → SOUTHWESTERN BELL 9533 NORMAN OK
— 405-574 0XXX which blocks → SOUTHWESTERN BELL 9533 CHICKASHA OK
— 405-576 3XXX8XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-577 0XXX1XXX6XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 YUKON OK
— 405-579 not yet reported which blocks → SOUTHWESTERN BELL 9533 NORMAN OK
— 405-586 0XXX2XXX3XXX4XXX5XXX6XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 MERIDIAN OK
— 405-599 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-616 0XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-619 8XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-620 none assigned yet which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-621 3XXX4XXX7XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BETHANY OK
— 405-624 not yet reported which blocks → SOUTHWESTERN BELL 9533 STILLWATER OK
— 405-629 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-630 none assigned yet which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-631 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-632 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-634 6XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-635 4XXX5XXX6XXX7XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-636 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-643 0XXX4XXX6XXX7XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 FORT COBB OK
— 405-644 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-645 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 CALVIN OK
— 405-649 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 MULHALL OK
— 405-656 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 BINGER OK
— 405-665 0XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 WYNNEWOOD OK
— 405-670 9XXX which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-671 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-672 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-677 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-680 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-681 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK
— 405-682 not yet reported which blocks → SOUTHWESTERN BELL 9533 OKLA CITY OK

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.