NumberResearchRecent thousands-block assignments
13 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/19/2026
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 |
|---|---|---|---|---|---|---|---|
| 2005-10-20 | 831-707-6XXX | 6000–6999 | Assigned | METROPCS, INC. | 5562 | WATSONVL | CA |
| 2005-10-20 | 831-707-7XXX | 7000–7999 | Assigned | METROPCS, INC. | 5562 | WATSONVL | CA |
| 2005-10-20 | 831-707-8XXX | 8000–8999 | Assigned | METROPCS, INC. | 5562 | WATSONVL | CA |
| 2005-10-20 | 831-707-9XXX | 9000–9999 | Assigned | METROPCS, INC. | 5562 | WATSONVL | CA |
| 2005-10-19 | 831-525-1XXX | 1000–1999 | Assigned | METROPCS, INC. | 5562 | KING CITY | CA |
| 2005-10-19 | 831-537-3XXX | 3000–3999 | Assigned | METROPCS, INC. | 5562 | HOLLISTER | CA |
| 2005-10-19 | 831-537-4XXX | 4000–4999 | Assigned | METROPCS, INC. | 5562 | HOLLISTER | CA |
| 2005-10-19 | 831-537-5XXX | 5000–5999 | Assigned | METROPCS, INC. | 5562 | HOLLISTER | CA |
| 2005-10-19 | 831-774-1XXX | 1000–1999 | Assigned | METROPCS, INC. | 5562 | GONZALES | CA |
| 2005-10-12 | 831-331-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2005-10-05 | 831-540-6XXX | 6000–6999 | Assigned | METROPCS, INC. | 5562 | SALINAS | CA |
| 2005-09-20 | 831-207-5XXX | 5000–5999 | Assigned | T-MOBILE USA, INC. | 6529 | HOLLISTER | CA |
| 2005-09-20 | 831-240-7XXX | 7000–7999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SALINAS | CA |
| 2005-09-20 | 831-998-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SALINAS | CA |
| 2005-09-20 | 831-998-1XXX | 1000–1999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SALINAS | CA |
| 2005-09-15 | 831-406-7XXX | 7000–7999 | Assigned | T-MOBILE USA, INC. | 6529 | WATSONVL | CA |
| 2005-09-14 | 831-756-7XXX | 7000–7999 | Assigned | UTILITY TELECOM GROUP, LLC - CA | 9262 | SALINAS | CA |
| 2005-09-02 | 831-776-4XXX | 4000–4999 | Assigned | METROPCS, INC. | 5562 | SALINAS | CA |
| 2005-08-25 | 831-222-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 7229 | FELTON | CA |
| 2005-08-17 | 831-207-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | HOLLISTER | CA |
| 2005-08-17 | 831-207-1XXX | 1000–1999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | HOLLISTER | CA |
| 2005-08-17 | 831-233-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | MONTEREY | CA |
| 2005-08-17 | 831-241-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | MONTEREY | CA |
| 2005-08-16 | 831-217-1XXX | 1000–1999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | BOULDERCRK | CA |
| 2005-08-16 | 831-718-9XXX | 9000–9999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | 7240 | MONTEREY | CA |
| 2005-08-11 | 831-233-4XXX | 4000–4999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | MONTEREY | CA |
| 2005-08-11 | 831-430-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | SANTA CRUZ | CA |
| 2005-08-10 | 831-444-2XXX | 2000–2999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | SALINAS | CA |
| 2005-08-10 | 831-444-5XXX | 5000–5999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | SALINAS | CA |
| 2005-08-05 | 831-535-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2005-08-05 | 831-535-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2005-08-05 | 831-535-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2005-08-05 | 831-535-9XXX | 9000–9999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | SANTA CRUZ | CA |
| 2005-07-22 | 831-840-9XXX | 9000–9999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | WATSONVL | CA |
| 2005-07-20 | 831-295-1XXX | 1000–1999 | Assigned | T-MOBILE USA, INC. | 6529 | SANTA CRUZ | CA |
| 2005-07-13 | 831-240-6XXX | 6000–6999 | Assigned | T-MOBILE USA, INC. | 6529 | SALINAS | CA |
| 2005-07-11 | 831-609-5XXX | 5000–5999 | Assigned | ONVOY, LLC - CA | 649C | BEN LOMOND | CA |
| 2005-07-06 | 831-207-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | HOLLISTER | CA |
| 2005-07-06 | 831-221-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SAN ARDO | CA |
| 2005-07-06 | 831-223-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SOLEDAD | CA |
| 2005-07-06 | 831-240-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SALINAS | CA |
| 2005-07-06 | 831-263-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | KING CITY | CA |
| 2005-07-06 | 831-536-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | WATSONVL | CA |
| 2005-07-06 | 831-623-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SAN JUAN | CA |
| 2005-07-06 | 831-675-6XXX | 6000–6999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | GONZALES | CA |
| 2005-07-06 | 831-778-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SAN LUCAS | CA |
| 2005-07-06 | 831-856-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | GREENFIELD | CA |
| 2005-07-01 | 831-539-8XXX | 8000–8999 | Assigned | METROPCS, INC. | 5562 | WATSONVL | CA |
| 2005-06-28 | 831-250-6XXX | 6000–6999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | CARMEL | CA |
| 2005-06-28 | 831-298-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | CARMEL VLY | CA |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.