Thousands-blocks in 443-937

This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/19/2026

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

The ten 1,000-number thousand-blocks inside prefix 443-937 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 443 blocks

Most active assignees, all time — NPA 443

PEERLESS NETWORK OF MARYLAND, LLC 2

CORE COMMUNICATIONS, INC.- MD 2

BANDWIDTH.COM CLEC, LLC - MD 2

TELEPORT COMMUNICATIONS AMERICA, LLC - MD 1

PAETEC ITEL, LLC 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

Recent thousands-block assignments
Assigned	Thousands-block	Last 4 digits	Status	Assignee	OCN	Rate center	State
2004-03-04	443-937-0XXX	0000–0999	Assigned	CORE COMMUNICATIONS, INC.- MD	2593	UNION BDG	MD
2004-01-15	443-937-1XXX	1000–1999	Assigned	PAETEC ITEL, LLC	829J	UNION BDG	MD
2012-09-13	443-937-2XXX	2000–2999	Assigned	ONVOY, LLC - MD	876D	UNION BDG	MD
2010-12-14	443-937-3XXX	3000–3999	Assigned	BANDWIDTH.COM CLEC, LLC - MD	071F	UNION BDG	MD
2018-05-23	443-937-4XXX	4000–4999	Assigned	CORE COMMUNICATIONS, INC.- MD	2593	UNION BDG	MD
2011-03-07	443-937-5XXX	5000–5999	Assigned	BANDWIDTH.COM CLEC, LLC - MD	071F	UNION BDG	MD
2007-01-09	443-937-6XXX	6000–6999	Assigned	COMCAST IP PHONE, LLC	318J	UNION BDG	MD
2013-04-05	443-937-7XXX	7000–7999	Assigned	PEERLESS NETWORK OF MARYLAND, LLC	568G	UNION BDG	MD
2013-04-05	443-937-8XXX	8000–8999	Assigned	PEERLESS NETWORK OF MARYLAND, LLC	568G	UNION BDG	MD
—	443-937-9XXX	9000–9999	Reserved	TELEPORT COMMUNICATIONS AMERICA, LLC - MD	7325	UNION BDG	MD

Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.