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 857
COMCAST IP PHONE, LLC 71
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
2022-09-27 857-639-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2022-09-27 857-639-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2022-09-27 857-799-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2021-09-10 857-387-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J QUINCY MA
2019-04-10 857-349-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J WINTHROP MA
2019-02-28 857-760-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J WATERTOWN MA
2018-10-30 857-338-1XXX 1000–1999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2018-06-28 857-346-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2017-10-31 857-322-1XXX 1000–1999Assigned COMCAST IP PHONE, LLC 318J EASTBOSTON MA
2017-10-25 857-997-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J SOMERVILLE MA
2017-10-24 857-315-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2017-08-23 857-297-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J NEWTON MA
2016-08-17 857-772-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2016-04-25 857-320-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2016-02-02 857-363-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J EVERETT MA
2015-11-05 857-990-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2015-10-29 857-316-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J BRIGHTON MA
2015-09-10 857-309-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J DORCHESTER MA
2015-07-15 857-706-1XXX 1000–1999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2015-07-10 857-703-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J HYDE PARK MA
2015-06-29 857-957-0XXX 0000–0999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2014-12-29 857-310-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2014-10-02 857-308-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J ROXBURY MA
2014-09-09 857-304-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J WATERTOWN MA
2014-09-05 857-576-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J BROOKLINE MA
2014-08-05 857-285-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2014-06-06 857-776-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J CHELSEA MA
2014-05-05 857-317-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2014-05-05 857-317-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2014-05-05 857-317-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2014-04-30 857-242-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2014-03-19 857-317-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2014-01-10 857-267-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J MILTON MA
2014-01-09 857-273-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J JAMAICA PL MA
2013-11-01 857-829-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2013-10-21 857-305-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2013-09-18 857-256-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J EASTBOSTON MA
2013-09-09 857-271-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J DORCHESTER MA
2013-08-15 857-273-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J JAMAICA PL MA
2013-08-15 857-496-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J SO BOSTON MA
2013-07-17 857-267-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J MILTON MA
2013-06-10 857-496-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J SO BOSTON MA
2013-04-24 857-273-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J JAMAICA PL MA
2013-04-05 857-999-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2012-08-30 857-242-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J CAMBRIDGE MA
2012-08-22 857-265-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2012-08-22 857-265-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2012-06-15 857-250-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2012-05-31 857-250-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J BOSTON MA
2011-09-29 857-500-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J 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.