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
2014-07-16 520-415-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F NOGALES AZ
2014-07-16 520-442-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F BENSON AZ
2014-07-11 520-328-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J TUCSON AZ
2014-07-09 520-328-4XXX 4000–4999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2014-07-09 520-328-5XXX 5000–5999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2014-07-09 520-328-6XXX 6000–6999Assigned T-MOBILE USA, INC. 6529 TUCSON AZ
2014-07-01 520-422-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 BISBEE AZ
2014-07-01 520-987-1XXX 1000–1999Assigned METROPCS, INC. 5562 NOGALES AZ
2014-07-01 520-987-2XXX 2000–2999Assigned METROPCS, INC. 5562 NOGALES AZ
2014-07-01 520-987-3XXX 3000–3999Assigned METROPCS, INC. 5562 NOGALES AZ
2014-06-25 520-359-0XXX 0000–0999Assigned METROPCS, INC. 5562 TUCSON AZ
2014-06-25 520-359-2XXX 2000–2999Assigned METROPCS, INC. 5562 TUCSON AZ
2014-06-09 520-447-0XXX 0000–0999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2014-06-09 520-447-9XXX 9000–9999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2014-06-09 520-448-1XXX 1000–1999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2014-06-06 520-447-1XXX 1000–1999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2014-06-06 520-447-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2014-05-30 520-213-2XXX 2000–2999Assigned T-MOBILE USA, INC. 6529 CASAGRANDE AZ
2014-05-15 520-328-0XXX 0000–0999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-05-15 520-328-1XXX 1000–1999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-05-15 520-328-2XXX 2000–2999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-05-15 520-328-3XXX 3000–3999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-05-02 520-448-0XXX 0000–0999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F TUCSON AZ
2014-05-02 520-448-4XXX 4000–4999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F TUCSON AZ
2014-05-02 520-448-9XXX 9000–9999Assigned PEERLESS NETWORK OF ARIZONA, LLC - AZ 579F TUCSON AZ
2014-04-30 520-775-4XXX 4000–4999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-04-30 520-775-5XXX 5000–5999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-04-30 520-775-6XXX 6000–6999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-04-30 520-775-7XXX 7000–7999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-04-30 520-775-8XXX 8000–8999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-04-30 520-775-9XXX 9000–9999Assigned QWEST CORPORATION 9636 TUCSON AZ
2014-04-24 520-265-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F BENSON AZ
2014-04-24 520-415-3XXX 3000–3999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F NOGALES AZ
2014-04-17 520-447-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2014-04-17 520-447-3XXX 3000–3999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2014-04-11 520-539-0XXX 0000–0999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-1XXX 1000–1999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-3XXX 3000–3999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-4XXX 4000–4999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-5XXX 5000–5999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-6XXX 6000–6999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-7XXX 7000–7999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-8XXX 8000–8999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-11 520-539-9XXX 9000–9999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TUCSON AZ
2014-04-04 520-447-5XXX 5000–5999Assigned COMCAST IP PHONE, LLC 318J TUCSON AZ
2014-03-25 520-447-6XXX 6000–6999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2014-03-18 520-213-5XXX 5000–5999Assigned T-MOBILE USA, INC. 6529 CASAGRANDE AZ
2014-03-17 520-356-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F HAYDEN AZ
2014-03-03 520-447-7XXX 7000–7999Assigned ONVOY, LLC - AZ 630E TUCSON 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.