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 617
LEVEL 3 COMMUNICATIONS, LLC - MA 176
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
2020-02-25 617-655-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2019-12-16 617-798-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2016-12-20 617-377-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2016-12-20 617-377-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2014-10-03 617-213-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 NEWTON MA
2014-04-29 617-612-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2014-04-29 617-648-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2014-02-20 617-607-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2014-01-14 617-401-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2013-12-10 617-401-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2013-08-23 617-231-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2013-08-08 617-765-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 SO BOSTON MA
2013-01-10 617-936-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2013-01-10 617-936-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2012-10-02 617-977-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BELMONT MA
2012-06-20 617-580-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CHARLESTN MA
2012-05-31 617-607-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2012-05-23 617-326-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 DORCHESTER MA
2011-12-01 617-941-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 SOMERVILLE MA
2011-10-26 617-600-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2011-10-19 617-553-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 JAMAICA PL MA
2011-08-10 617-993-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BELMONT MA
2011-08-03 617-206-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BRIGHTON MA
2011-08-03 617-544-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 EVERETT MA
2011-08-03 617-934-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 QUINCY MA
2011-05-10 617-275-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2011-02-28 617-600-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2011-02-28 617-941-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 SOMERVILLE MA
2011-01-10 617-934-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 QUINCY MA
2010-01-07 617-600-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WATERTOWN MA
2008-07-15 617-284-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 SOMERVILLE MA
2008-05-07 617-477-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 JAMAICA PL MA
2008-05-06 617-206-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BRIGHTON MA
2008-05-06 617-391-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2008-05-06 617-681-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CHARLESTN MA
2008-04-16 617-841-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 WINTHROP MA
2008-03-07 617-963-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BOSTON MA
2008-02-19 617-800-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2008-02-08 617-300-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2008-02-07 617-505-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BROOKLINE MA
2008-02-05 617-379-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 DORCHESTER MA
2008-02-05 617-379-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 DORCHESTER MA
2008-02-04 617-340-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 NEWTON MA
2008-02-04 617-340-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 NEWTON MA
2008-02-04 617-674-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2008-02-04 617-674-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
2008-01-31 617-409-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CHELSEA MA
2008-01-31 617-409-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CHELSEA MA
2008-01-23 617-860-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 BROOKLINE MA
2008-01-22 617-245-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA

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.