NumberResearch Membership · Data 09/20/2026

Recent thousands-block assignments

17 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 443
ONVOY, LLC - MD 8
NEW CINGULAR WIRELESS PCS, LLC - DC 4
VERSATEL LLC 1
OPENTACT INC. 1
LEVEL 3 COMMUNICATIONS, LLC - MD 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
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Recent thousands-block assignments
AssignedThousands-blockLast 4 digitsStatusAssigneeOCNRate centerState
2018-05-23 443-843-4XXX 4000–4999Assigned CORE COMMUNICATIONS, INC.- MD 2593 HAVREGRACE MD
2018-05-23 443-892-5XXX 5000–5999Assigned CORE COMMUNICATIONS, INC.- MD 2593 NEWWINDSOR MD
2018-05-23 443-893-5XXX 5000–5999Assigned CORE COMMUNICATIONS, INC.- MD 2593 WOODLAWN MD
2018-05-23 443-893-6XXX 6000–6999Assigned CORE COMMUNICATIONS, INC.- MD 2593 WOODLAWN MD
2018-05-23 443-937-4XXX 4000–4999Assigned CORE COMMUNICATIONS, INC.- MD 2593 UNION BDG MD
2018-05-21 443-731-5XXX 5000–5999Assigned ONVOY, LLC - MD 876D PT DEPOSIT MD
2018-05-11 443-264-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F PIKESVILLE MD
2018-05-11 443-596-7XXX 7000–7999Assigned NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ESSEX MD
2018-05-11 443-678-3XXX 3000–3999Assigned NEW CINGULAR WIRELESS PCS, LLC - DC 4036 PARKVILLE MD
2018-05-11 443-782-5XXX 5000–5999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F ANNAPOLIS MD
2018-05-10 443-920-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F SYKESVILLE MD
2018-05-10 443-920-5XXX 5000–5999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F SYKESVILLE MD
2018-05-02 443-264-3XXX 3000–3999Assigned ONVOY, LLC - MD 876D PIKESVILLE MD
2018-05-02 443-582-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F CHURCHVL MD
2018-05-02 443-645-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F MILLERSVL MD
2018-05-01 443-530-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - MD 071F DUNDALK MD
2018-04-30 443-396-7XXX 7000–7999Assigned ONVOY, LLC - MD 876D ODENTON MD
2018-04-30 443-495-6XXX 6000–6999Assigned ONVOY, LLC - MD 876D PARKVILLE MD
2018-04-30 443-596-6XXX 6000–6999Assigned ONVOY, LLC - MD 876D ESSEX MD
2018-04-30 443-782-4XXX 4000–4999Assigned ONVOY, LLC - MD 876D ANNAPOLIS MD
2018-04-20 443-437-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 POCOMOKE MD
2018-04-05 443-364-1XXX 1000–1999Assigned METROPCS, INC. 5562 ELLICOTTCY MD
2018-03-23 443-649-7XXX 7000–7999Assigned METROPCS, INC. 5562 SPARROWSPT MD
2018-03-23 443-922-4XXX 4000–4999Assigned METROPCS, INC. 5562 EDGEWOOD MD
2018-03-05 443-628-7XXX 7000–7999Assigned NEW CINGULAR WIRELESS PCS, LLC - DC 4036 GLENBURNIE MD
2018-03-05 443-734-4XXX 4000–4999Assigned NEW CINGULAR WIRELESS PCS, LLC - DC 4036 SEVERN MD
2018-03-05 443-936-7XXX 7000–7999Assigned NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ELKRIDGE MD
2018-02-28 443-953-3XXX 3000–3999Assigned METROPCS, INC. 5562 SALISBURY MD
2018-02-20 443-381-5XXX 5000–5999Assigned METROPCS, INC. 5562 REISTERSTN MD
2018-02-09 443-439-4XXX 4000–4999Assigned PEERLESS NETWORK OF MARYLAND, LLC 568G TRAPPE MD
2018-02-02 443-609-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J SYKESVILLE MD
2018-01-15 443-381-8XXX 8000–8999Assigned METROPCS, INC. 5562 REISTERSTN MD
2018-01-15 443-666-0XXX 0000–0999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 CHESTERTN MD
2018-01-15 443-679-2XXX 2000–2999Assigned METROPCS, INC. 5562 SEVERN MD
2018-01-15 443-922-1XXX 1000–1999Assigned METROPCS, INC. 5562 EDGEWOOD MD
2018-01-10 443-441-5XXX 5000–5999Assigned MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 7228 GLENWOOD MD
2018-01-08 443-781-3XXX 3000–3999Assigned COMCAST IP PHONE, LLC 318J ARGRGBSNIS MD
2018-01-05 443-628-9XXX 9000–9999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 GLENBURNIE MD
2018-01-05 443-947-0XXX 0000–0999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 PERRYVILLE MD
2018-01-05 443-981-1XXX 1000–1999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 FALLSTON MD
2017-12-29 443-450-6XXX 6000–6999Assigned COMCAST IP PHONE, LLC 318J PIKESVILLE MD
2017-12-15 443-782-8XXX 8000–8999Assigned IDT AMERICA, CORP. - MD 228C ANNAPOLIS MD
2017-12-15 443-972-7XXX 7000–7999Assigned IDT AMERICA, CORP. - MD 228C CAMBRIDGE MD
2017-12-13 443-337-4XXX 4000–4999Assigned METROPCS, INC. 5562 SPARROWSPT MD
2017-12-13 443-881-6XXX 6000–6999Assigned METROPCS, INC. 5562 REISTERSTN MD
2017-12-13 443-953-2XXX 2000–2999Assigned METROPCS, INC. 5562 SALISBURY MD
2017-12-11 443-795-8XXX 8000–8999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 SEVERN MD
2017-11-16 443-836-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2017-11-16 443-836-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
2017-11-15 443-477-5XXX 5000–5999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 CAMBRIDGE MD

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.