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 |
|---|---|---|---|---|---|---|
| 2022-01-27 | 475-548 | 0–9 XXXall 10 · 2 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | MERIDEN | CT |
| 2022-01-27 | 475-644 | 2XXX4XXX · 2 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | GEORGETOWN | CT |
| 2022-01-25 | 475-467 | 0–9 XXXall 10 · 8 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | TRUMBULL | CT |
| 2022-01-25 | 475-639 | 0XXX1XXX2XXX3XXX4XXX7XXX · 2 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | REDDING | CT |
| 2022-01-24 | 475-382 | 0–9 XXXall 10 · 4 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | BRANFORD | CT |
| 2022-01-18 | 475-463 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | SEYMOUR | CT |
| 2022-01-18 | 475-763 | 0–9 XXXall 10 · 4 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | NAUGATUCK | CT |
| 2022-01-17 | 475-622 | 0XXX1XXX2XXX3XXX5XXX8XXX · 5 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | WOLCOTT | CT |
| 2022-01-13 | 475-327 | 0–9 XXXall 10 · 4 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | MILFORD | CT |
| 2022-01-13 | 475-426 | 0–9 XXXall 10 · 5 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | RIDGEFIELD | CT |
| 2022-01-13 | 475-466 | 0–9 XXXall 10 · 5 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | MADISON | CT |
| 2022-01-13 | 475-887 | 0–9 XXXall 10 · 5 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | WESTPORT | CT |
| 2022-01-10 | 475-673 | 0–9 XXXall 10 · 3 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | NORWALK | CT |
| 2022-01-10 | 475-832 | 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | WILTON | CT |
| 2022-01-07 | 475-342 | 0–9 XXXall 10 · 4 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | ANSONIDRBY | CT |
| 2022-01-07 | 475-746 | 0–9 XXXall 10 · 6 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | STAMFORD | CT |
| 2020-10-29 | 475-837 | 0–9 XXXall 10 · 5 holders which blocks → | TON80 COMMUNICATIONS, LLC | 516J | NEW HAVEN | CT |
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.