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 251
LEVEL 3 COMMUNICATIONS, LLC - AL 109
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
2024-05-31 251-242-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 CHATOM AL
2023-02-14 251-521-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 GRAND BAY AL
2023-02-06 251-321-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 ATMORE AL
2021-12-13 251-870-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MONROEVL AL
2021-11-16 251-240-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2021-09-23 251-228-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2021-08-04 251-361-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2021-06-15 251-228-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2021-05-18 251-215-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2021-03-09 251-850-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FAIRHOPE AL
2020-12-29 251-910-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-11-17 251-724-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-11-05 251-215-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2020-09-22 251-620-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-08-18 251-328-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-06-05 251-326-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2020-04-28 251-200-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2020-03-31 251-318-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2019-09-10 251-306-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 IRNGTNSTEL AL
2019-07-17 251-283-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2019-07-10 251-215-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2018-10-31 251-200-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2017-08-29 251-264-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2017-05-31 251-213-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2016-03-17 251-378-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-12-30 251-378-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-11-13 251-472-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-11-13 251-472-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-11-10 251-800-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-10-20 251-800-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-09-16 251-405-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-07-23 251-239-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 BAYMINETTE AL
2015-07-23 251-405-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2015-06-23 251-415-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2014-09-24 251-303-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2014-07-31 251-662-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2014-07-02 251-308-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MOBILE AL
2014-06-11 251-216-8XXX 8000–8999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 EVERGREEN AL
2014-06-04 251-299-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 MT VERNON AL
2014-04-11 251-271-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 FOLEY AL
2014-04-11 251-276-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - AL 5255 COFFEEVL AL

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.