NumberResearch Membership · Data 09/20/2026

Recent thousands-block assignments

0 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/20/2026

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

Most carrier growth happens here, not at the prefix level: under number pooling, carriers receive individual 1,000-number blocks (e.g. 626-470-0XXX) within already-assigned prefixes. Assignments are initial assignments — the current serving carrier of individual numbers may differ due to portability.

Most active assignees, all time — NPA 410
LEVEL 3 COMMUNICATIONS, LLC - MD 144
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 thousands-block assignments
AssignedThousands-blockLast 4 digitsStatusAssigneeOCNRate centerState
2023-06-20 410-214-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 RISING SUN MD
2019-01-09 410-319-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2018-12-05 410-816-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 TOWSON MD
2017-10-17 410-291-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2016-09-22 410-226-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 OXFORD MD
2016-09-22 410-348-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 STILL POND MD
2016-09-22 410-438-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SUDLERSVL MD
2015-07-23 410-525-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2015-07-23 410-525-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2015-04-14 410-525-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2015-03-27 410-943-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 HURLOCK MD
2015-03-24 410-216-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ANNAPOLIS MD
2014-06-24 410-469-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2014-06-24 410-469-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2013-12-11 410-928-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 MILLINGTON MD
2013-05-30 410-648-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 GALENA MD
2013-01-09 410-775-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 UNION BDG MD
2012-07-05 410-695-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ODENTON MD
2011-11-08 410-394-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SOLOMONS MD
2011-10-12 410-885-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 CHESAPKECY MD
2011-10-12 410-927-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ODENTON MD
2011-08-11 410-927-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ODENTON MD
2011-06-14 410-346-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SILVER RUN MD
2011-03-10 410-472-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SPARKSGLNC MD
2010-08-27 410-690-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 EASTON MD
2010-07-16 410-246-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2010-03-05 410-779-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2009-09-30 410-858-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ANNAPOLIS MD
2009-09-29 410-305-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ODENTON MD
2009-09-29 410-696-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ELLICOTTCY MD
2009-08-05 410-929-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2009-08-03 410-690-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 EASTON MD
2008-11-26 410-415-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 PIKESVILLE MD
2008-09-10 410-709-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SPARROWSPT MD
2008-09-10 410-914-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 CHURCHVL MD
2008-08-27 410-927-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ODENTON MD
2008-08-27 410-942-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 HAVREGRACE MD
2008-05-06 410-394-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SOLOMONS MD
2008-05-06 410-696-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ELLICOTTCY MD
2008-05-05 410-575-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 FORK MD
2008-04-28 410-317-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ARGRGBSNIS MD
2008-04-28 410-412-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 GLENBURNIE MD
2008-04-28 410-595-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 GLENBURNIE MD
2008-04-18 410-424-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 GLENBURNIE MD
2008-04-16 410-881-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SHERWD FOR MD
2008-04-14 410-849-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SHERWD FOR MD
2008-03-24 410-589-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BRYNPKLNCM MD
2008-03-24 410-928-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 MILLINGTON MD
2008-03-03 410-344-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 CHASE MD
2008-02-05 410-384-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 SEVERNA PK MD

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.