NumberResearchRecent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026
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 |
|---|---|---|---|---|---|---|
| 2020-08-28 | 310-565 | 0–9 XXXall 10 · 3 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | EL SEGUNDO | CA |
| 2017-07-03 | 310-682 | 0–9 XXXwhole prefix which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | HAWTHORNE | CA |
| — | 310-228 | 0XXX7XXX8XXX which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | BEVERLYHLS | CA |
| — | 310-237 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | CULVERCITY | CA |
| — | 310-242 | 0XXX1XXX3XXX7XXX8XXX · 3 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | INGLEWOOD | CA |
| — | 310-309 | 0XXX1XXX7XXX9XXX which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | SNMN SNMN | CA |
| — | 310-341 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | EL SEGUNDO | CA |
| — | 310-343 | 0XXX1XXX2XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | EL SEGUNDO | CA |
| — | 310-357 | 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | TORRANCE | CA |
| — | 310-369 | not yet reported which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | BEVERLYHLS | CA |
| — | 310-525 | 0XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | CMTN GRDN | CA |
| — | 310-531 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | HAWTHORNE | CA |
| — | 310-598 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | BEVERLYHLS | CA |
| — | 310-633 | 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | SNMN SNMN | CA |
| — | 310-683 | 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 6 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | REDONDO | CA |
| — | 310-689 | 4XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | W ANGELES | CA |
| — | 310-744 | 0XXX1XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | EL SEGUNDO | CA |
| — | 310-754 | 0XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | SNMN MRVS | CA |
| — | 310-969 | not yet reported which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | BEVERLYHLS | CA |
| — | 310-981 | 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | INGLEWOOD | CA |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.