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 424
T-MOBILE USA, INC. 74
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
2025-06-05 424-556 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 SNMN SNMN CA
2024-11-08 424-520 0XXX6XXX7XXX9XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2024-09-09 424-516 0–9 XXXall 10 · 7 holders which blocks → T-MOBILE USA, INC. 6529 LOMITA CA
2024-07-30 424-514 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 W ANGELES CA
2024-05-31 424-513 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2024-05-10 424-547 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 INGLEWOOD CA
2024-05-01 424-510 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2022-12-28 424-485 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2022-12-01 424-483 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 W ANGELES CA
2022-08-15 424-482 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 SAN PEDRO CA
2022-08-12 424-470 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2022-03-21 424-481 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 HAWTHORNE CA
2022-02-10 424-473 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 SAN PEDRO CA
2022-01-14 424-467 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 W ANGELES CA
2022-01-07 424-471 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 REDONDO CA
2021-12-10 424-475 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 TORRANCE CA
2021-12-02 424-468 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2021-11-18 424-462 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 SAN PEDRO CA
2021-11-10 424-463 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 INGLEWOOD CA
2021-10-28 424-454 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2021-10-04 424-469 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 CMTN GRDN CA
2021-08-17 424-457 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2021-06-17 424-449 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2021-03-19 424-448 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2020-02-05 424-415 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 CMTN GRDN CA
2019-08-07 424-437 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 HAWTHORNE CA
2019-08-05 424-436 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 SNMN SNMN CA
2019-06-18 424-440 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 W ANGELES CA
2019-05-28 424-435 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 TORRANCE CA
2019-05-10 424-429 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2019-01-31 424-420 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 INGLEWOOD CA
2018-01-10 424-489 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 SAN PEDRO CA
2016-11-02 424-403 0–9 XXXall 10 · 7 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2016-09-21 424-421 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2016-08-31 424-537 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 SNMN MRVS CA
2016-08-29 424-390 0–9 XXXall 10 · 7 holders which blocks → T-MOBILE USA, INC. 6529 REDONDO CA
2016-06-28 424-366 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2016-04-29 424-308 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 SAN PEDRO CA
2015-09-22 424-303 0–9 XXXall 10 · 7 holders which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2015-07-02 424-527 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2015-04-16 424-535 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 W ANGELES CA
2015-04-13 424-521 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 CMTN CMTN CA
2015-04-13 424-523 0–9 XXXall 10 · 8 holders which blocks → T-MOBILE USA, INC. 6529 CULVERCITY CA
2015-03-09 424-391 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 HAWTHORNE CA
2015-03-09 424-396 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 CMTN GRDN CA
2015-02-24 424-386 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 BEVERLYHLS CA
2015-02-24 424-395 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 MALIBU CA
2015-01-23 424-387 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 SNMN SNMN CA
2015-01-20 424-385 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 CULVERCITY CA
2014-12-30 424-393 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 INGLEWOOD CA

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.