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 |
|---|---|---|---|---|---|---|
| 2016-11-14 | 563-253 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | TIPTON | IA |
| 2015-10-30 | 563-339 | 3XXX5XXX9XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | SUMNER | IA |
| 2015-06-25 | 563-635 | 1XXX3XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | LE CLAIRE | IA |
| 2015-06-25 | 563-655 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | DE WITT | IA |
| 2015-06-24 | 563-228 | 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 7 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | BELLEVUE | IA |
| — | 563-237 | 0XXX2XXX3XXX4XXX7XXX8XXX · 5 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | FREDECKSBG | IA |
| — | 563-289 | 7XXX8XXX · 2 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | LE CLAIRE | IA |
| — | 563-522 | 0XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | LOW MOOR | IA |
| — | 563-578 | 6XXX7XXX9XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | SUMNER | IA |
| — | 563-649 | 0XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | ATALISSA | IA |
| — | 563-659 | 6XXX7XXX · 2 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | DE WITT | IA |
| — | 563-674 | 2XXX3XXX6XXX7XXX8XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | DELMAR | IA |
| — | 563-677 | 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | CHARLOTTE | IA |
| — | 563-687 | 4XXX7XXX8XXX · 2 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | SABULA | IA |
| — | 563-724 | 2XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | MOSCOW | IA |
| — | 563-785 | 2XXX3XXX5XXX7XXX8XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | DURANT | IA |
| — | 563-872 | 2XXX6XXX7XXX8XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | BELLEVUE | IA |
| — | 563-886 | 4XXX5XXX7XXX8XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | TIPTON | IA |
| — | 563-893 | 3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | BENNETT | IA |
| — | 563-944 | 0XXX3XXX4XXX6XXX8XXX9XXX · 5 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | LOWDEN | IA |
| — | 563-945 | 2XXX4XXX5XXX7XXX · 3 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | STANWOOD | IA |
| — | 563-946 | 4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → | WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS | 1170 | ROCHESTER | IA |
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.