NumberResearch Membership · Data 09/20/2026

Recent thousands-block assignments

0 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, all time — NPA 831
COMCAST PHONE OF CALIFORNIA, LLC 57
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
2022-09-20 831-289-3XXX 3000–3999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L BEN LOMOND CA
2022-06-09 831-308-9XXX 9000–9999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CARMEL VLY CA
2022-06-09 831-309-7XXX 7000–7999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CARMEL CA
2022-06-09 831-309-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CARMEL CA
2022-05-31 831-215-1XXX 1000–1999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2022-05-31 831-215-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2020-08-19 831-356-0XXX 0000–0999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2020-03-04 831-439-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2019-08-27 831-257-4XXX 4000–4999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L APTOS CA
2019-04-02 831-208-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2019-03-04 831-717-3XXX 3000–3999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2018-09-04 831-202-0XXX 0000–0999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2018-08-21 831-453-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CASTROVL CA
2017-06-23 831-641-7XXX 7000–7999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2017-05-05 831-201-4XXX 4000–4999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2017-03-15 831-256-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2015-07-29 831-226-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2015-07-15 831-574-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CARMEL CA
2015-03-27 831-610-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L BOULDERCRK CA
2015-03-13 831-704-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L FELTON CA
2014-11-24 831-718-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2014-10-02 831-346-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2014-08-29 831-800-3XXX 3000–3999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2014-06-18 831-901-3XXX 3000–3999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2013-11-08 831-612-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L APTOS CA
2013-08-26 831-316-7XXX 7000–7999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2013-07-23 831-621-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2013-06-03 831-250-5XXX 5000–5999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CARMEL CA
2013-04-08 831-800-7XXX 7000–7999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2012-12-19 831-884-5XXX 5000–5999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2011-09-01 831-471-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2011-08-31 831-676-0XXX 0000–0999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2011-07-11 831-241-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2010-08-06 831-431-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2009-07-21 831-293-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L CARMEL CA
2009-04-30 831-975-5XXX 5000–5999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2009-03-09 831-661-5XXX 5000–5999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L APTOS CA
2008-11-26 831-717-4XXX 4000–4999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2008-08-04 831-975-4XXX 4000–4999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2008-07-16 831-713-5XXX 5000–5999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2008-02-22 831-324-4XXX 4000–4999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2007-01-12 831-998-7XXX 7000–7999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2007-01-12 831-998-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SALINAS CA
2006-12-27 831-920-1XXX 1000–1999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2006-12-27 831-920-2XXX 2000–2999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L MONTEREY CA
2006-10-05 831-600-7XXX 7000–7999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2006-10-05 831-600-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2006-04-07 831-609-6XXX 6000–6999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L BEN LOMOND CA
2006-04-03 831-454-8XXX 8000–8999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L SANTA CRUZ CA
2006-04-03 831-703-4XXX 4000–4999Assigned COMCAST PHONE OF CALIFORNIA, LLC 394L BOULDERCRK 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.