NumberResearch Membership · Data 09/21/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/21/2026

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
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
2014-10-24 224-503 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2014-09-02 224-386 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 PALATINE IL
2014-07-25 224-830 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2014-07-21 224-508 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2014-07-16 224-818 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ROUND LAKE IL
2014-06-11 224-385 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → T-MOBILE USA, INC. 6529 BARRINGTON IL
2014-06-11 224-713 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2014-06-11 224-817 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2014-03-05 224-334 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2014-01-28 224-774 0XXX1XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 ZION IL
2013-10-16 224-281 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2013-09-20 224-814 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 ROUND LAKE IL
2013-07-09 224-336 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2013-07-09 224-413 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2013-07-09 224-415 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2013-07-09 224-432 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 GLENVIEW IL
2013-06-25 224-253 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2013-06-21 224-248 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2013-06-13 224-806 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2013-05-24 224-409 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2013-05-24 224-410 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2013-04-18 224-247 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2013-04-18 224-427 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 BARRINGTON IL
2012-08-10 224-256 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2012-05-02 224-308 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ROUND LAKE IL
2012-01-23 224-803 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2011-09-08 224-226 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2011-09-08 224-261 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2011-07-21 224-245 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2011-07-18 224-237 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2011-07-11 224-235 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2011-03-03 224-733 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2011-03-03 224-800 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2011-02-10 224-600 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ALGONQUIN IL
2010-10-04 224-276 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2008-10-06 224-523 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2007-09-29 224-343 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2007-09-29 224-548 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2007-09-28 224-387 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2007-09-28 224-795 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2007-09-12 224-637 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 WAUKEGAN IL
2007-08-21 224-565 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2007-07-10 224-425 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2007-06-05 224-645 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 NORTHBROOK IL
2007-04-24 224-465 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2006-12-21 224-856 0–9 XXXall 10 · 7 holders which blocks → T-MOBILE USA, INC. 6529 ELGIN IL
2006-11-29 224-587 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 ARLIGTNHTS IL
2006-09-20 224-789 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 ZION IL
2006-04-25 224-433 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 LIBERTYVL IL
2005-12-06 224-616 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 GLENVIEW IL

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/21/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.