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
Clear Download CSV ↓
Recent thousands-block assignments
AssignedThousands-blockLast 4 digitsStatusAssigneeOCNRate centerState
2011-06-07 520-288-3XXX 3000–3999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-06-07 520-288-4XXX 4000–4999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-06-07 520-288-5XXX 5000–5999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-05-27 520-509-5XXX 5000–5999Assigned T-MOBILE USA, INC. 6529 CASAGRANDE AZ
2011-05-02 520-375-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F NOGALES AZ
2011-04-25 520-366-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 BISBEE AZ
2011-04-25 520-368-8XXX 8000–8999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 DOUGLAS AZ
2011-04-25 520-457-8XXX 8000–8999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 TOMBSTONE AZ
2011-04-22 520-288-0XXX 0000–0999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-04-22 520-288-1XXX 1000–1999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-04-22 520-288-2XXX 2000–2999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-04-13 520-450-4XXX 4000–4999Assigned GILA LOCAL EXCHANGE CARRIER, INC. - AZ 947E CASAGRANDE AZ
2011-04-08 520-610-3XXX 3000–3999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 SACATON AZ
2011-03-29 520-314-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-5XXX 5000–5999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-314-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-724-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-29 520-724-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-03-17 520-477-0XXX 0000–0999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2011-03-15 520-449-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J TUCSON AZ
2011-03-15 520-561-8XXX 8000–8999Assigned COMCAST IP PHONE, LLC 318J TUCSON AZ
2011-03-10 520-450-7XXX 7000–7999Assigned T-MOBILE USA, INC. 6529 CASAGRANDE AZ
2011-02-15 520-314-4XXX 4000–4999Assigned LEVEL 3 COMMUNICATIONS, LLC - AZ 3285 TUCSON AZ
2011-02-04 520-724-2XXX 2000–2999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-04 520-724-3XXX 3000–3999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-04 520-724-4XXX 4000–4999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-04 520-724-5XXX 5000–5999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-04 520-724-6XXX 6000–6999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-04 520-724-7XXX 7000–7999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-04 520-724-8XXX 8000–8999Assigned QWEST CORPORATION 9636 TUCSON AZ
2011-02-03 520-858-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 6572 CASAGRANDE AZ
2011-02-02 520-561-5XXX 5000–5999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-02-02 520-561-6XXX 6000–6999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-02-02 520-561-7XXX 7000–7999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 TUCSON AZ
2011-01-24 520-201-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F SAN MANUEL AZ
2011-01-18 520-216-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F NOGALES AZ
2011-01-18 520-477-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-01-18 520-477-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-01-18 520-477-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-01-18 520-477-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-01-18 520-477-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-01-18 520-477-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - AZ 587F TUCSON AZ
2011-01-14 520-255-7XXX 7000–7999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 SIERRAVIST AZ
2011-01-07 520-549-0XXX 0000–0999Assigned MCIMETRO ACCESS TRANSMISSION SERVICES LLC - AZ 7465 TUCSON AZ
2011-01-06 520-463-9XXX 9000–9999Assigned MCC TELEPHONY LLC 593K WHITLOW 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.