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 |
|---|---|---|---|---|---|---|
| 2014-10-01 | 224-478 | 0–9 XXXall 10 · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | DESPLAINES | IL |
| 2012-04-20 | 224-215 | 0–9 XXXall 10 · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | WILMETTE | IL |
| 2010-09-22 | 224-999 | 0–9 XXXall 10 · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | EVANSTON | IL |
| 2010-08-03 | 224-888 | 0–9 XXXall 10 · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | CARY | IL |
| 2006-10-09 | 224-788 | 0–9 XXXall 10 · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | ANTIOCH | IL |
| 2006-06-19 | 224-678 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | ALGONQUIN | IL |
| 2006-05-12 | 224-699 | 0XXX2XXX3XXX4XXX5XXX9XXX · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | DUNDEE | IL |
| 2006-04-03 | 224-513 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | LIBERTYVL | IL |
| 2005-12-30 | 224-655 | 0–9 XXXall 10 · 7 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | BARRINGTON | IL |
| 2005-12-29 | 224-585 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | PARK RIDGE | IL |
| 2005-09-01 | 224-286 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | LAKEZURICH | IL |
| 2005-06-29 | 224-603 | 0–9 XXXall 10 · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | ANTIOCH | IL |
| 2005-03-30 | 224-366 | 0–9 XXXall 10 · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | ELK GROVE | IL |
| 2005-03-11 | 224-543 | 0–9 XXXall 10 · 7 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | HALF DAY | IL |
| 2005-03-11 | 224-778 | 0–9 XXXall 10 · 8 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | MUNDELEIN | IL |
| 2005-03-11 | 224-993 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 7 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | WAUCONDA | IL |
| 2005-02-28 | 224-633 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | BARRINGTON | IL |
| 2004-12-16 | 224-267 | 0–9 XXXall 10 · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | ANTIOCH | IL |
| — | 224-677 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | LAKEZURICH | IL |
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.