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 |
|---|---|---|---|---|---|---|
| 2015-03-09 | 641-854 | 0–9 XXXall 10 · 6 holders which blocks → | QWEST CORPORATION | 9631 | MARSHALLTN | IA |
| 2010-08-18 | 641-428 | 0–9 XXXall 10 · 3 holders which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| 2001-04-24 | 641-752 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MARSHALLTN | IA |
| 2001-04-24 | 641-753 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MARSHALLTN | IA |
| 2001-04-24 | 641-754 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MARSHALLTN | IA |
| — | 641-228 | 0XXX which blocks → | QWEST CORPORATION | 9631 | CHARLES CY | IA |
| — | 641-257 | 7XXX8XXX9XXX which blocks → | QWEST CORPORATION | 9631 | CHARLES CY | IA |
| — | 641-324 | 5XXX6XXX7XXX8XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | NORTHWOOD | IA |
| — | 641-380 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| — | 641-421 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| — | 641-422 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| — | 641-423 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| — | 641-424 | not yet reported which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| — | 641-435 | 0XXX1XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | NASHUA | IA |
| — | 641-454 | 0XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | QWEST CORPORATION | 9631 | MANLY | IA |
| — | 641-456 | 6XXX7XXX8XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | HAMPTON | IA |
| — | 641-458 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | GENEVA | IA |
| — | 641-494 | 4XXX6XXX7XXX8XXX9XXX which blocks → | QWEST CORPORATION | 9631 | MASON CITY | IA |
| — | 641-632 | 0XXX1XXX2XXX3XXX4XXX6XXX7XXX9XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | ROSE HILL | IA |
| — | 641-648 | not yet reported which blocks → | QWEST CORPORATION | 9631 | IOWA FALLS | IA |
| — | 641-672 | 4XXX5XXX6XXX7XXX · 4 holders which blocks → | QWEST CORPORATION | 9631 | OSKALOOSA | IA |
| — | 641-673 | not yet reported which blocks → | QWEST CORPORATION | 9631 | OSKALOOSA | IA |
| — | 641-682 | not yet reported which blocks → | QWEST CORPORATION | 9631 | OTTUMWA | IA |
| — | 641-683 | not yet reported which blocks → | QWEST CORPORATION | 9631 | OTTUMWA | IA |
| — | 641-684 | not yet reported which blocks → | QWEST CORPORATION | 9631 | OTTUMWA | IA |
| — | 641-732 | 0XXX2XXX7XXX8XXX9XXX · 5 holders which blocks → | QWEST CORPORATION | 9631 | OSAGE | IA |
| — | 641-843 | 0XXX6XXX7XXX8XXX · 4 holders which blocks → | QWEST CORPORATION | 9631 | BRITT | IA |
| — | 641-844 | 3XXX4XXX7XXX8XXX · 2 holders which blocks → | QWEST CORPORATION | 9631 | MARSHALLTN | IA |
| — | 641-847 | 0XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | ACKLEY | IA |
| — | 641-923 | 1XXX7XXX8XXX · 3 holders which blocks → | QWEST CORPORATION | 9631 | GARNER | 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.