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 331
COMCAST IP PHONE, LLC 61
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
2024-03-21 331-850-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J BIG ROCK IL
2023-04-14 331-252-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J WARRENVL IL
2023-02-22 331-334-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J BATAVIA IL
2022-10-05 331-291-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2022-10-05 331-291-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2022-10-05 331-631-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2022-10-05 331-631-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2022-09-20 331-286-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J ST CHARLES IL
2022-09-20 331-286-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J ST CHARLES IL
2019-09-13 331-249-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2019-03-25 331-233-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2017-08-15 331-707-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J AURORA IL
2017-05-03 331-226-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2016-12-30 331-871-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J W CHICAGO IL
2016-09-26 331-204-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2016-08-11 331-757-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J LEMONT IL
2016-07-18 331-716-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J WHEATON IL
2016-06-21 331-300-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J AURORA IL
2016-03-21 331-979-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J ELMHURST IL
2016-01-15 331-401-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2016-01-06 331-775-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2015-09-30 331-901-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J ST CHARLES IL
2015-09-25 331-998-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2015-09-14 331-814-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2015-08-03 331-307-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J LOMBARD IL
2015-06-23 331-301-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J AURORA IL
2015-06-12 331-806-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J WHEATON IL
2015-06-09 331-903-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2015-04-16 331-701-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2015-03-24 331-216-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J OSWEGO IL
2015-03-05 331-979-0XXX 0000–0999Assigned COMCAST IP PHONE, LLC 318J ELMHURST IL
2015-03-05 331-979-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J ELMHURST IL
2014-09-25 331-903-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2014-08-20 331-302-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J AURORA IL
2014-08-04 331-318-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J LEMONT IL
2014-07-31 331-225-0XXX 0000–0999Assigned COMCAST IP PHONE, LLC 318J ELMHURST IL
2014-06-26 331-248-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J GENEVA IL
2014-06-26 331-318-7XXX 7000–7999Assigned COMCAST IP PHONE, LLC 318J LEMONT IL
2014-06-18 331-209-9XXX 9000–9999Assigned COMCAST IP PHONE, LLC 318J ELMHURST IL
2014-06-10 331-702-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2014-06-10 331-777-9XXX 9000–9999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2014-05-14 331-207-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J YORKVILLE IL
2014-04-04 331-256-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J AURORA IL
2014-03-24 331-218-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J WHEATON IL
2013-11-08 331-229-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2013-11-08 331-240-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J W CHICAGO IL
2013-11-08 331-777-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2013-11-07 331-251-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL
2013-07-22 331-229-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J NAPERVILLE IL
2013-06-25 331-777-2XXX 2000–2999Assigned COMCAST IP PHONE, LLC 318J DOWNERSGRV IL

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.