NumberResearchRecent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/22/2026
The Code holder is who opened each NPA-NXX prefix — not necessarily who holds the numbers. A prefix is 10,000 numbers, but under pooling its ten 1,000-number blocks are handed out individually, often to different carriers; the code holder may hold only one block, or none. The Thousands-blocks column shows how the ten blocks are really split — click which blocks → to see who holds each 1,000-number block and its last-4-digit range. Assignments are initial assignments; the current serving carrier may differ due to portability.
| Assigned | NPA-NXX | Thousands-blocks taken (last-4 opening) | Code holder | OCN | Rate center | State |
|---|---|---|---|---|---|---|
| 2001-01-26 | 951-965 | 0XXX2XXX4XXX5XXX · 2 holders which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-283 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | CORONA | CA |
| — | 951-334 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-347 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-378 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | PERRIS | CA |
| — | 951-426 | 0–9 XXXall 10 · 4 holders which blocks → | T-MOBILE USA, INC. | 6529 | HEMT SNJC | CA |
| — | 951-436 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → | T-MOBILE USA, INC. | 6529 | PERRIS | CA |
| — | 951-442 | 0–9 XXXall 10 · 3 holders which blocks → | T-MOBILE USA, INC. | 6529 | PERRIS | CA |
| — | 951-453 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-515 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | CORONA | CA |
| — | 951-536 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-538 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-544 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-550 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → | T-MOBILE USA, INC. | 6529 | PERRIS | CA |
| — | 951-575 | 0–9 XXXall 10 · 5 holders which blocks → | T-MOBILE USA, INC. | 6529 | PERRIS | CA |
| — | 951-662 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-667 | 0–9 XXXall 10 · 9 holders which blocks → | T-MOBILE USA, INC. | 6529 | TEMSCL CNY | CA |
| — | 951-712 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-830 | none assigned yet which blocks → | T-MOBILE USA, INC. | 6529 | RIVERSIDE | CA |
| — | 951-973 | 0–9 XXXall 10 · 5 holders which blocks → | T-MOBILE USA, INC. | 6529 | MURRIETA | CA |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/22/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.