NumberResearch Membership · Data 09/20/2026

Recent thousands-block assignments

11 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, last 30 days — NPA 331
ONVOY, LLC 6
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 3
NEW CINGULAR WIRELESS PCS, LLC - IL 1
BANDWIDTH.COM CLEC, LLC - IL 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
Clear Download CSV ↓
Recent thousands-block assignments
AssignedThousands-blockLast 4 digitsStatusAssigneeOCNRate centerState
2014-04-23 331-256-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E AURORA IL
2014-04-23 331-256-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E AURORA IL
2014-04-23 331-305-3XXX 3000–3999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E NAPERVILLE IL
2014-04-23 331-305-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E NAPERVILLE IL
2014-04-23 331-305-5XXX 5000–5999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E NAPERVILLE IL
2014-04-16 331-305-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - IL 6115 NAPERVILLE IL
2014-04-04 331-256-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J AURORA IL
2014-03-26 331-208-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - IL 6115 AURORA IL
2014-03-24 331-218-4XXX 4000–4999Assigned COMCAST IP PHONE, LLC 318J WHEATON IL
2014-03-21 331-229-9XXX 9000–9999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 6333 NAPERVILLE IL
2014-03-20 331-422-4XXX 4000–4999Assigned ONVOY, LLC 224C ST CHARLES IL
2014-03-20 331-703-3XXX 3000–3999Assigned ONVOY, LLC 224C W CHICAGO IL
2014-03-12 331-777-7XXX 7000–7999Assigned LEVEL 3 TELECOM OF ILLINOIS, LLC - IL 138G DOWNERSGRV IL
2014-02-28 331-245-4XXX 4000–4999Assigned T-MOBILE USA, INC. 6529 BARTLETT IL
2014-02-28 331-245-5XXX 5000–5999Assigned T-MOBILE USA, INC. 6529 BARTLETT IL
2014-02-28 331-245-6XXX 6000–6999Assigned T-MOBILE USA, INC. 6529 BARTLETT IL
2014-02-28 331-250-8XXX 8000–8999Assigned T-MOBILE USA, INC. 6529 AURORA IL
2014-02-28 331-302-1XXX 1000–1999Assigned T-MOBILE USA, INC. 6529 AURORA IL
2014-02-28 331-302-2XXX 2000–2999Assigned T-MOBILE USA, INC. 6529 AURORA IL
2014-02-28 331-302-3XXX 3000–3999Assigned T-MOBILE USA, INC. 6529 AURORA IL
2014-02-28 331-302-4XXX 4000–4999Assigned T-MOBILE USA, INC. 6529 AURORA IL
2014-02-26 331-318-5XXX 5000–5999Assigned FIRST COMMUNICATIONS, LLC 460K LEMONT IL
2014-02-19 331-251-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E DOWNERSGRV IL
2014-02-19 331-251-3XXX 3000–3999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E DOWNERSGRV IL
2014-02-19 331-251-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E DOWNERSGRV IL
2014-02-14 331-225-4XXX 4000–4999Assigned ONVOY, LLC 224C ELMHURST IL
2014-02-13 331-240-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E W CHICAGO IL
2014-02-13 331-240-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E W CHICAGO IL
2014-02-13 331-303-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E ELBURN IL
2014-02-13 331-303-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E ELBURN IL
2014-02-06 331-228-0XXX 0000–0999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 6333 ST CHARLES IL
2014-01-30 331-318-6XXX 6000–6999Assigned LEVEL 3 TELECOM OF ILLINOIS, LLC - IL 138G LEMONT IL
2014-01-30 331-703-7XXX 7000–7999Assigned CENTURYLINK COMMUNICATIONS, LLC 508J W CHICAGO IL
2014-01-23 331-218-5XXX 5000–5999Assigned T-MOBILE USA, INC. 6529 WHEATON IL
2014-01-23 331-218-6XXX 6000–6999Assigned T-MOBILE USA, INC. 6529 WHEATON IL
2014-01-23 331-218-7XXX 7000–7999Assigned T-MOBILE USA, INC. 6529 WHEATON IL
2014-01-22 331-218-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E WHEATON IL
2014-01-22 331-218-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E WHEATON IL
2014-01-22 331-218-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E WHEATON IL
2014-01-22 331-218-3XXX 3000–3999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E WHEATON IL
2014-01-22 331-234-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E SUGARGROVE IL
2014-01-22 331-234-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E SUGARGROVE IL
2014-01-22 331-234-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E SUGARGROVE IL
2014-01-21 331-248-5XXX 5000–5999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E GENEVA IL
2014-01-21 331-248-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E GENEVA IL
2014-01-21 331-318-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E LEMONT IL
2014-01-21 331-318-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E LEMONT IL
2014-01-21 331-318-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E LEMONT IL
2014-01-15 331-318-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - IL 6115 LEMONT IL
2014-01-14 331-888-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - IL 984E WARRENVL 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.