NumberResearch Membership · Data 09/20/2026

Thousands-blocks in 575-499

This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/20/2026

Full prefixes (NXX) Thousands-blocks (1,000-number pools)

The ten 1,000-number thousand-blocks inside prefix 575-499 and who was initially assigned each. Under pooling these blocks often belong to different carriers — the single prefix-level “assignee” is usually just the pool / code holder, not who holds the numbers. ← all 575 blocks

Most active assignees, all time — NPA 575
NEW CINGULAR WIRELESS PCS, LLC - IL 4
MESCALERO APACHE TELECOM, INC. - NM 3
METROPCS, INC. 2
T-MOBILE USA, INC. 1
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 thousands-block assignments
AssignedThousands-blockLast 4 digitsStatusAssigneeOCNRate centerState
— 575-499-0XXX 0000–0999Reserved MESCALERO APACHE TELECOM, INC. - NM 661D CARLSBAD NM
— 575-499-1XXX 1000–1999Reserved MESCALERO APACHE TELECOM, INC. - NM 661D CARLSBAD NM
— 575-499-2XXX 2000–2999Reserved MESCALERO APACHE TELECOM, INC. - NM 661D CARLSBAD NM
2006-11-21 575-499-3XXX 3000–3999Assigned NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CARLSBAD NM
2006-12-19 575-499-4XXX 4000–4999Assigned NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CARLSBAD NM
2007-12-17 575-499-5XXX 5000–5999Assigned NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CARLSBAD NM
2008-03-19 575-499-6XXX 6000–6999Assigned NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CARLSBAD NM
2011-03-01 575-499-7XXX 7000–7999Assigned METROPCS, INC. 5562 CARLSBAD NM
2007-05-07 575-499-8XXX 8000–8999Assigned METROPCS, INC. 5562 CARLSBAD NM
2006-12-06 575-499-9XXX 9000–9999Assigned T-MOBILE USA, INC. 6529 CARLSBAD NM

Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.