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 |
|---|---|---|---|---|---|---|
| — | 406-342 | 2XXX which blocks → | RANGE TEL COOP INC | 2251 | HYSHAM | MT |
| — | 406-347 | not yet reported which blocks → | RANGE TEL COOP INC | 2251 | ROSEBUD | MT |
| — | 406-421 | 0XXX2XXX which blocks → | RANGE TEL COOP INC | 2251 | SOMILES CY | MT |
| — | 406-427 | not yet reported which blocks → | RANGE TEL COOP INC | 2251 | SO BROADUS | MT |
| — | 406-436 | 8XXX which blocks → | RANGE TEL COOP INC | 2251 | BROADUS | MT |
| — | 406-477 | 1XXX which blocks → | RANGE TEL COOP INC | 2251 | LAME DEER | MT |
| — | 406-554 | not yet reported which blocks → | RANGE TEL COOP INC | 2251 | NO BROADUS | MT |
| — | 406-592 | none assigned yet which blocks → | RANGE TEL COOP INC | 2251 | BUSBY | MT |
| — | 406-757 | 7XXX which blocks → | RANGE TEL COOP INC | 2251 | DECKER | MT |
| — | 406-784 | none assigned yet which blocks → | RANGE TEL COOP INC | 2251 | ASHLAND | MT |
| — | 406-828 | 8XXX which blocks → | RANGE TEL COOP INC | 2251 | ALZADA | MT |
| — | 406-984 | none assigned yet which blocks → | RANGE TEL COOP INC | 2251 | BIRNEY | MT |
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.