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 |
|---|---|---|---|---|---|---|
| 2019-03-26 | 413-305 | 0XXX1XXX2XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | TC SYSTEMS, INC. | 7135 | SOUTHWICK | MA |
| 2009-05-15 | 413-350 | 0XXX1XXX2XXX3XXX5XXX6XXX9XXX · 5 holders which blocks → | TC SYSTEMS, INC. | 7135 | SO DEERFLD | MA |
| — | 413-225 | 1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → | TC SYSTEMS, INC. | 7135 | NORTHFIELD | MA |
| — | 413-231 | 0XXX2XXX3XXX4XXX6XXX7XXX8XXX which blocks → | TC SYSTEMS, INC. | 7135 | SPRINGFLD | MA |
| — | 413-240 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → | TC SYSTEMS, INC. | 7135 | CHICOPEE | MA |
| — | 413-275 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | TC SYSTEMS, INC. | 7135 | HOLYOKE | MA |
| — | 413-325 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | TC SYSTEMS, INC. | 7135 | GREENFIELD | MA |
| — | 413-429 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | TC SYSTEMS, INC. | 7135 | GREATBNGTN | MA |
| — | 413-449 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | TC SYSTEMS, INC. | 7135 | PITTSFIELD | MA |
| — | 413-475 | 0–9 XXXall 10 · 7 holders which blocks → | TC SYSTEMS, INC. | 7135 | GREENFIELD | MA |
| — | 413-504 | 2XXX3XXX8XXX9XXX · 2 holders which blocks → | TC SYSTEMS, INC. | 7135 | SPRINGFLD | MA |
| — | 413-559 | 0XXX1XXX2XXX3XXX7XXX8XXX9XXX · 3 holders which blocks → | TC SYSTEMS, INC. | 7135 | AMHRSTFKLN | MA |
| — | 413-579 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | TC SYSTEMS, INC. | 7135 | WESTFIELD | MA |
| — | 413-588 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | TC SYSTEMS, INC. | 7135 | NORTHAMPTN | MA |
| — | 413-631 | 1XXX4XXX6XXX which blocks → | TC SYSTEMS, INC. | 7135 | LUDLOW | MA |
| — | 413-672 | 0XXX1XXX2XXX3XXX4XXX7XXX8XXX9XXX · 6 holders which blocks → | TC SYSTEMS, INC. | 7135 | NORTHADAMS | MA |
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.