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 |
|---|---|---|---|---|---|---|
| 2008-08-12 | 608-665 | 0–9 XXXall 10 · 4 holders which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| 2004-06-17 | 608-333 | 0–9 XXXall 10 · 2 holders which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| 2002-02-15 | 608-443 | 6XXX7XXX8XXX9XXX which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| 2001-05-08 | 608-442 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-203 | 5XXX6XXX8XXX9XXX which blocks → | TDS METROCOM, LLC | 520K | MIDDLETON | WI |
| — | 608-204 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-205 | 2XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | TDS METROCOM, LLC | 520K | STOUGHTON | WI |
| — | 608-210 | 9XXX which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-230 | 0XXX5XXX6XXX which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-308 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-310 | 4XXX5XXX which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-313 | 2XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → | TDS METROCOM, LLC | 520K | BELOIT | WI |
| — | 608-314 | 4XXX5XXX6XXX7XXX which blocks → | TDS METROCOM, LLC | 520K | JANESVILLE | WI |
| — | 608-321 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-441 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-446 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-661 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-662 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MIDDLETON | WI |
| — | 608-663 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MADISON | WI |
| — | 608-664 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | MIDDLETON | WI |
| — | 608-750 | not yet reported which blocks → | TDS METROCOM, LLC | 520K | JANESVILLE | WI |
| — | 608-855 | 0XXX1XXX2XXX4XXX5XXX7XXX8XXX9XXX · 7 holders which blocks → | TDS METROCOM, LLC | 520K | SPARTA | 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.