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 |
|---|---|---|---|---|---|---|
| 2022-01-31 | 608-816 | 0–9 XXXall 10 · 7 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | LA CROSSE | WI |
| 2021-11-05 | 608-810 | 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | PORTAGE | WI |
| 2019-10-08 | 608-668 | 0–9 XXXall 10 · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | LA CROSSE | WI |
| 2019-04-22 | 608-716 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| 2017-10-09 | 608-517 | 0XXX1XXX2XXX3XXX4XXX6XXX7XXX9XXX · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | FENNIMORE | WI |
| 2017-09-28 | 608-708 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | DEERFIELD | WI |
| 2014-11-25 | 608-699 | 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | CAMBRIDGE | WI |
| 2014-10-03 | 608-416 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| 2006-02-10 | 608-492 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | STOUGHTON | WI |
| 2005-11-09 | 608-729 | 0–9 XXXall 10 · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| 2003-04-17 | 608-498 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | LA CROSSE | WI |
| 2003-02-05 | 608-554 | 0XXX1XXX2XXX3XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | JANESVILLE | WI |
| 2002-10-21 | 608-561 | 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | EDGERTON | WI |
| 2002-05-13 | 608-466 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | BELOIT | WI |
| 2002-05-13 | 608-467 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| 2002-03-14 | 608-433 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | LA CROSSE | WI |
| — | 608-227 | none assigned yet which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| — | 608-229 | 1XXX which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| — | 608-327 | 5XXX9XXX · 2 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| — | 608-478 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | SUNPRAIRIE | WI |
| — | 608-512 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
| — | 608-713 | 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | BELOIT | WI |
| — | 608-807 | 2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - WI | 5489 | MADISON | WI |
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.