NumberResearchRecent thousands-block assignments
13 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/20/2026
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
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
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2014-05-20 | 831-975-9XXX | 9000–9999 | Assigned | METROPCS, INC. | 5562 | SALINAS | CA |
| 2014-05-13 | 831-508-6XXX | 6000–6999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | FELTON | CA |
| 2014-05-01 | 831-296-6XXX | 6000–6999 | Assigned | T-MOBILE USA, INC. | 6529 | SALINAS | CA |
| 2014-05-01 | 831-747-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | MONTEREY | CA |
| 2014-04-24 | 831-337-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOULDERCRK | CA |
| 2014-04-24 | 831-609-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BEN LOMOND | CA |
| 2014-04-24 | 831-612-5XXX | 5000–5999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | APTOS | CA |
| 2014-04-22 | 831-291-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | 7240 | SANTA CRUZ | CA |
| 2014-04-18 | 831-296-1XXX | 1000–1999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SALINAS | CA |
| 2014-04-07 | 831-291-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2014-04-07 | 831-291-1XXX | 1000–1999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2014-04-07 | 831-291-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2014-04-02 | 831-245-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | HOLLISTER | CA |
| 2014-04-02 | 831-298-9XXX | 9000–9999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | CARMEL VLY | CA |
| 2014-04-01 | 831-582-7XXX | 7000–7999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | MONTEREY | CA |
| 2014-03-19 | 831-732-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SAN ARDO | CA |
| 2014-03-13 | 831-465-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SANTA CRUZ | CA |
| 2014-03-12 | 831-428-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | SANTA CRUZ | CA |
| 2014-03-12 | 831-536-6XXX | 6000–6999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | WATSONVL | CA |
| 2014-03-06 | 831-540-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SALINAS | CA |
| 2014-03-06 | 831-737-6XXX | 6000–6999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SALINAS | CA |
| 2014-02-28 | 831-221-8XXX | 8000–8999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | SAN ARDO | CA |
| 2014-02-28 | 831-524-8XXX | 8000–8999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | HOLLISTER | CA |
| 2014-02-28 | 831-677-6XXX | 6000–6999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | SOLEDAD | CA |
| 2014-02-27 | 831-275-3XXX | 3000–3999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | MONTEREY | CA |
| 2014-02-27 | 831-275-4XXX | 4000–4999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | MONTEREY | CA |
| 2014-02-27 | 831-275-5XXX | 5000–5999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | MONTEREY | CA |
| 2014-02-27 | 831-508-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | FELTON | CA |
| 2014-02-27 | 831-856-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | GREENFIELD | CA |
| 2014-02-12 | 831-713-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2014-01-28 | 831-272-6XXX | 6000–6999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SALINAS | CA |
| 2014-01-23 | 831-884-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | MONTEREY | CA |
| 2013-12-23 | 831-316-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2013-12-04 | 831-265-3XXX | 3000–3999 | Assigned | T-MOBILE USA, INC. | 6529 | HOLLISTER | CA |
| 2013-12-04 | 831-295-7XXX | 7000–7999 | Assigned | T-MOBILE USA, INC. | 6529 | SANTA CRUZ | CA |
| 2013-12-04 | 831-319-7XXX | 7000–7999 | Assigned | T-MOBILE USA, INC. | 6529 | WATSONVL | CA |
| 2013-11-08 | 831-612-6XXX | 6000–6999 | Assigned | COMCAST PHONE OF CALIFORNIA, LLC | 394L | APTOS | CA |
| 2013-10-14 | 831-784-8XXX | 8000–8999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | 7240 | SALINAS | CA |
| 2013-10-11 | 831-920-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | MONTEREY | CA |
| 2013-10-09 | 831-313-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | HOLLISTER | CA |
| 2013-09-23 | 831-998-5XXX | 5000–5999 | Assigned | METROPCS, INC. | 5562 | SALINAS | CA |
| 2013-09-10 | 831-789-6XXX | 6000–6999 | Assigned | T-MOBILE USA, INC. | 6529 | SALINAS | CA |
| 2013-08-29 | 831-718-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | 7240 | MONTEREY | CA |
| 2013-08-27 | 831-287-3XXX | 3000–3999 | Assigned | U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | 671J | SALINAS | CA |
| 2013-08-26 | 831-316-7XXX | 7000–7999 | Assigned | COMCAST PHONE OF CALIFORNIA, LLC | 394L | SANTA CRUZ | CA |
| 2013-08-14 | 831-296-9XXX | 9000–9999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SALINAS | CA |
| 2013-08-09 | 831-290-3XXX | 3000–3999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | GONZALES | CA |
| 2013-07-23 | 831-621-2XXX | 2000–2999 | Assigned | COMCAST PHONE OF CALIFORNIA, LLC | 394L | SANTA CRUZ | CA |
| 2013-07-02 | 831-237-9XXX | 9000–9999 | Assigned | METROPCS, INC. | 5562 | SOLEDAD | CA |
| 2013-07-02 | 831-998-6XXX | 6000–6999 | Assigned | METROPCS, INC. | 5562 | 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.