NumberResearch Membership · Data 09/20/2026

Recent thousands-block assignments

13 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 831
ONVOY, LLC - CA 10
EXIANT COMMUNICATIONS LLC 2
BANDWIDTH.COM CLEC, LLC - CA 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
Clear Download CSV ↓
Recent thousands-block assignments
AssignedThousands-blockLast 4 digitsStatusAssigneeOCNRate centerState
2011-12-07 831-574-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - CA 8826 CARMEL CA
2011-11-30 831-975-2XXX 2000–2999Assigned LEVEL 3 COMMUNICATIONS, LLC - CA 8826 SALINAS CA
2011-11-18 831-406-6XXX 6000–6999Assigned U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J WATSONVL CA
2011-11-11 831-684-7XXX 7000–7999Assigned LEVEL 3 COMMUNICATIONS, LLC - CA 8826 APTOS CA
2011-11-02 831-296-7XXX 7000–7999Assigned METROPCS, INC. 5562 SALINAS CA
2011-10-28 831-293-5XXX 5000–5999Assigned MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA 7240 CARMEL CA
2011-10-19 831-293-4XXX 4000–4999Assigned NEW CINGULAR WIRELESS PCS, LLC 6010 CARMEL CA
2011-09-19 831-319-1XXX 1000–1999Assigned T-MOBILE USA, INC. 6529 WATSONVL CA
2011-09-14 831-205-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E HOLLISTER CA
2011-09-14 831-217-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C BOULDERCRK CA
2011-09-14 831-290-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C GONZALES CA
2011-09-14 831-508-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C FELTON CA
2011-09-14 831-525-8XXX 8000–8999Assigned AT&T ENTERPRISES, LLC 516C KING CITY CA
2011-09-14 831-532-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C BEN LOMOND CA
2011-09-14 831-593-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C SAN JUAN CA
2011-09-14 831-627-4XXX 4000–4999Assigned AT&T ENTERPRISES, LLC 516C SAN ARDO CA
2011-09-14 831-628-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C TRES PINOS CA
2011-09-01 831-471-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2011-09-01 831-824-2XXX 2000–2999Assigned PAETEC ITEL, LLC 829J SANTA CRUZ CA
2011-08-31 831-676-0XXX 0000–0999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2011-08-30 831-676-4XXX 4000–4999Assigned METROPCS, INC. 5562 SALINAS CA
2011-08-24 831-676-1XXX 1000–1999Assigned METROPCS, INC. 5562 SALINAS CA
2011-08-04 831-287-2XXX 2000–2999Assigned U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J SALINAS CA
2011-08-03 831-264-7XXX 7000–7999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E MONTEREY CA
2011-08-03 831-264-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E MONTEREY CA
2011-07-26 831-232-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C CHUALAR CA
2011-07-22 831-824-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E SANTA CRUZ CA
2011-07-21 831-319-8XXX 8000–8999Assigned T-MOBILE USA, INC. 6529 WATSONVL CA
2011-07-19 831-708-1XXX 1000–1999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E APTOS CA
2011-07-19 831-708-6XXX 6000–6999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E APTOS CA
2011-07-13 831-676-2XXX 2000–2999Assigned TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 SALINAS CA
2011-07-11 831-241-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2011-07-11 831-461-4XXX 4000–4999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 SANTA CRUZ CA
2011-07-06 831-789-5XXX 5000–5999Assigned METROPCS, INC. 5562 SALINAS CA
2011-07-01 831-264-6XXX 6000–6999Assigned TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 MONTEREY CA
2011-06-30 831-687-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E APTOS CA
2011-06-30 831-687-9XXX 9000–9999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E APTOS CA
2011-06-27 831-205-3XXX 3000–3999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E HOLLISTER CA
2011-06-22 831-297-4XXX 4000–4999Assigned METROPCS, INC. 5562 HOLLISTER CA
2011-06-08 831-237-5XXX 5000–5999Assigned AT&T ENTERPRISES, LLC 516C SOLEDAD CA
2011-06-08 831-406-3XXX 3000–3999Assigned METROPCS, INC. 5562 WATSONVL CA
2011-06-08 831-406-4XXX 4000–4999Assigned METROPCS, INC. 5562 WATSONVL CA
2011-06-08 831-770-9XXX 9000–9999Assigned METROPCS, INC. 5562 SALINAS CA
2011-06-08 831-775-9XXX 9000–9999Assigned METROPCS, INC. 5562 SALINAS CA
2011-05-31 831-204-8XXX 8000–8999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E MONTEREY CA
2011-05-31 831-296-4XXX 4000–4999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E SALINAS CA
2011-05-26 831-296-5XXX 5000–5999Assigned LEVEL 3 COMMUNICATIONS, LLC - CA 8826 SALINAS CA
2011-05-10 831-620-2XXX 2000–2999Assigned CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 CARMEL CA
2011-04-28 831-296-0XXX 0000–0999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E SALINAS CA
2011-04-28 831-296-2XXX 2000–2999Assigned BANDWIDTH.COM CLEC, LLC - CA 981E SALINAS CA

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.