NumberResearch Membership · Data 09/20/2026

Recent thousands-block assignments

5 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 520
NEW CINGULAR WIRELESS PCS, LLC 3
INTRADO COMMUNICATIONS, LLC 2
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
2013-03-28 520-371-5XXX 5000–5999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F CASAGRANDE AZ
2013-03-28 520-391-6XXX 6000–6999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F SUPERIOR AZ
2013-03-28 520-391-9XXX 9000–9999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F SUPERIOR AZ
2013-03-28 520-463-3XXX 3000–3999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F WHITLOW AZ
2013-03-28 520-510-0XXX 0000–0999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F CASAGRANDE AZ
2013-03-22 520-332-6XXX 6000–6999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2013-03-22 520-433-9XXX 9000–9999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2013-03-14 520-268-0XXX 0000–0999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-03-14 520-268-1XXX 1000–1999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-03-14 520-268-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-03-12 520-200-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F HAYDEN AZ
2013-03-12 520-224-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J SIERRAVIST AZ
2013-03-11 520-252-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 CASAGRANDE AZ
2013-03-04 520-450-8XXX 8000–8999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 CASAGRANDE AZ
2013-02-28 520-373-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J TUCSON AZ
2013-02-25 520-415-2XXX 2000–2999Assigned ONVOY, LLC - AZ 630E NOGALES AZ
2013-02-25 520-896-4XXX 4000–4999Assigned ONVOY, LLC - AZ 630E SAN MANUEL AZ
2013-02-21 520-442-1XXX 1000–1999Assigned ONVOY, LLC - AZ 630E BENSON AZ
2013-02-20 520-335-0XXX 0000–0999Assigned ONVOY, LLC - AZ 630E SIERRAVIST AZ
2013-02-20 520-337-1XXX 1000–1999Assigned ONVOY, LLC - AZ 630E WILLCOX AZ
2013-02-20 520-356-5XXX 5000–5999Assigned ONVOY, LLC - AZ 630E HAYDEN AZ
2013-02-19 520-999-0XXX 0000–0999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2013-02-13 520-433-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-02-01 520-368-6XXX 6000–6999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 DOUGLAS AZ
2013-02-01 520-368-7XXX 7000–7999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 DOUGLAS AZ
2013-01-16 520-895-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 SIERRAVIST AZ
2013-01-15 520-286-0XXX 0000–0999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-286-1XXX 1000–1999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-286-2XXX 2000–2999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-286-3XXX 3000–3999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-286-4XXX 4000–4999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-345-0XXX 0000–0999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-1XXX 1000–1999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-3XXX 3000–3999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-4XXX 4000–4999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-7XXX 7000–7999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-8XXX 8000–8999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-345-9XXX 9000–9999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2013-01-15 520-427-0XXX 0000–0999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-1XXX 1000–1999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-2XXX 2000–2999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-3XXX 3000–3999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-4XXX 4000–4999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-5XXX 5000–5999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-6XXX 6000–6999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-7XXX 7000–7999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2013-01-15 520-427-8XXX 8000–8999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2012-12-26 520-422-7XXX 7000–7999Assigned ONVOY, LLC - AZ 630E BISBEE AZ
2012-12-26 520-422-8XXX 8000–8999Assigned ONVOY, LLC - AZ 630E BISBEE AZ

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.