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 435
T-MOBILE USA, INC. 41
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
2025-12-03 435-369 7XXX9XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 BRIGHAM CY UT
2025-08-28 435-365 6XXX7XXX8XXX9XXX which blocks → T-MOBILE USA, INC. 6529 HEBER CITY UT
2024-05-31 435-360 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
2024-05-23 435-328 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → T-MOBILE USA, INC. 6529 HEBER CITY UT
2012-08-15 435-339 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 BRIGHAM CY UT
2011-11-21 435-414 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
2011-09-19 435-319 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
2011-07-06 435-549 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 VERNAL UT
2011-01-27 435-525 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
2010-07-23 435-314 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 EPHRAIM UT
2007-10-25 435-374 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 LOGAN UT
2007-07-12 435-219 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 VERNAL UT
2006-12-20 435-282 1XXX2XXX4XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 TREMONTON UT
2004-08-12 435-621 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 VERNAL UT
2002-10-18 435-862 0XXX1XXX2XXX3XXX4XXX5XXX which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
2002-02-21 435-580 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 NEPHI UT
2001-08-17 435-313 not yet reported which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
2001-08-17 435-327 3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → T-MOBILE USA, INC. 6529 CEDAR CITY UT
2001-06-27 435-224 0XXX1XXX5XXX6XXX7XXX8XXX9XXX which blocks → T-MOBILE USA, INC. 6529 TOOELE UT
2001-06-27 435-225 1XXX7XXX8XXX9XXX which blocks → T-MOBILE USA, INC. 6529 BRIGHAM CY UT
2001-05-11 435-239 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 BRIGHAM CY UT
— 435-229 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
— 435-232 0XXX5XXX7XXX8XXX which blocks → T-MOBILE USA, INC. 6529 LOGAN UT
— 435-237 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 BRIGHAM CY UT
— 435-241 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → T-MOBILE USA, INC. 6529 TOOELE UT
— 435-267 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 CEDAR CITY UT
— 435-294 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 LOGAN UT
— 435-496 1XXX2XXX4XXX5XXX6XXX7XXX8XXX which blocks → T-MOBILE USA, INC. 6529 TOOELE UT
— 435-512 not yet reported which blocks → T-MOBILE USA, INC. 6529 LOGAN UT
— 435-513 3XXX6XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 PARK CITY UT
— 435-531 0XXX2XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 CEDAR CITY UT
— 435-602 1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → T-MOBILE USA, INC. 6529 PARK CITY UT
— 435-701 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → T-MOBILE USA, INC. 6529 CEDAR CITY UT
— 435-703 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
— 435-705 1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 ST GEORGE UT
— 435-714 3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 PARK CITY UT
— 435-731 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → T-MOBILE USA, INC. 6529 PARK CITY UT
— 435-764 not yet reported which blocks → T-MOBILE USA, INC. 6529 LOGAN UT
— 435-850 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 TOOELE UT
— 435-962 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 PARK CITY UT
— 435-994 2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 LOGAN UT

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.