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 |
|---|---|---|---|---|---|---|
| 2002-02-04 | 815-215 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → | FIRST COMMUNICATIONS, LLC | 460K | NEW LENOX | IL |
| 2001-10-23 | 815-518 | 1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 7 holders which blocks → | FIRST COMMUNICATIONS, LLC | 460K | COAL CITY | IL |
| — | 815-330 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | CRESCENTCY | IL |
| — | 815-413 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | MORRIS | IL |
| — | 815-418 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → | FIRST COMMUNICATIONS, LLC | 460K | MANHATTAN | IL |
| — | 815-430 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | MCHENRY | IL |
| — | 815-460 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | JOLIET | IL |
| — | 815-487 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | PLAINFIELD | IL |
| — | 815-502 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | WOODSTOCK | IL |
| — | 815-504 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | GARDNER | IL |
| — | 815-512 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | LOCKPORT | IL |
| — | 815-602 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | KANKAKEE | IL |
| — | 815-606 | not yet reported which blocks → | FIRST COMMUNICATIONS, LLC | 460K | OTTAWA | IL |
| — | 815-717 | 0XXX1XXX3XXX4XXX6XXX8XXX · 5 holders which blocks → | FIRST COMMUNICATIONS, LLC | 460K | NEW LENOX | 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.