NumberResearch Membership · Data 09/22/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/22/2026

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 224
T-MOBILE USA, INC. 138
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
2005-12-06 224-770 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 BARRINGTON IL
2005-11-21 224-260 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → T-MOBILE USA, INC. 6529 GLENVIEW IL
2005-06-30 224-848 0XXX1XXX2XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 BARRINGTON IL
2005-04-22 224-355 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2005-04-22 224-636 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2005-03-28 224-538 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2005-02-21 224-377 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 6 holders which blocks → T-MOBILE USA, INC. 6529 HALF DAY IL
2005-02-18 224-388 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2004-11-24 224-220 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 DESPLAINES IL
2004-11-22 224-210 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2003-02-19 224-305 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2002-10-18 224-522 not yet reported which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2002-10-18 224-717 2XXX3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 ZION IL
2002-10-18 224-805 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2002-10-17 224-280 0XXX1XXX2XXX3XXX4XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2002-09-25 224-875 3XXX6XXX7XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 ELK GROVE IL
2002-09-23 224-392 not yet reported which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2002-08-30 224-730 3XXX4XXX5XXX6XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 ZION IL
2002-08-13 224-659 5XXX7XXX which blocks → T-MOBILE USA, INC. 6529 ELK GROVE IL
2002-07-30 224-628 7XXX which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2002-07-15 224-595 not yet reported which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2002-06-19 224-715 not yet reported which blocks → T-MOBILE USA, INC. 6529 LIBERTYVL IL
2002-06-10 224-489 none assigned yet which blocks → T-MOBILE USA, INC. 6529 BARRINGTON IL
2002-06-07 224-436 5XXX6XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 LAKEFOREST IL
2002-06-05 224-558 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2002-04-30 224-627 none assigned yet which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2002-04-19 224-402 6XXX7XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2002-03-28 224-622 not yet reported which blocks → T-MOBILE USA, INC. 6529 BARRINGTON IL
2002-01-17 224-577 0XXX1XXX2XXX3XXX4XXX · 5 holders which blocks → T-MOBILE USA, INC. 6529 ROUND LAKE IL
2001-11-13 224-381 7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2001-11-13 224-578 6XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 PALATINE IL
2001-11-13 224-619 0XXX1XXX3XXX4XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 DEERFIELD IL
2001-11-13 224-623 0XXX6XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2001-11-13 224-766 1XXX2XXX3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 GLENVIEW IL
2001-10-18 224-629 1XXX2XXX4XXX5XXX8XXX9XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
— 224-400 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
— 224-424 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 LIBERTYVL IL
— 224-550 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 ELK GROVE IL

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/22/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.