NumberResearchThousands-blocks in 406-300
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/20/2026
The ten 1,000-number thousand-blocks inside prefix 406-300 and who was initially assigned each. Under pooling these blocks often belong to different carriers — the single prefix-level “assignee” is usually just the pool / code holder, not who holds the numbers. ← all 406 blocks
Most active assignees, all time — NPA 406
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
Mar 2026
Feb 2026
Jan 2026
Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2016-04-06 | 406-300-0XXX | 0000–0999 | Assigned | ONVOY, LLC - MT | 453F | KALISPELL | MT |
| 2013-07-19 | 406-300-1XXX | 1000–1999 | Assigned | CHARTER IP ENABLED SERVICES, LLC | 792K | KALISPELL | MT |
| 2014-06-17 | 406-300-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT | 6564 | KALISPELL | MT |
| 2017-05-03 | 406-300-3XXX | 3000–3999 | Assigned | ONVOY, LLC - MT | 453F | KALISPELL | MT |
| 2016-06-29 | 406-300-4XXX | 4000–4999 | Assigned | ONVOY, LLC - MT | 453F | KALISPELL | MT |
| 2017-10-23 | 406-300-5XXX | 5000–5999 | Assigned | ONVOY, LLC - MT | 453F | KALISPELL | MT |
| 2014-05-13 | 406-300-6XXX | 6000–6999 | Assigned | TELEPORT COMMUNICATIONS AMERICA MT - LLC | 771G | KALISPELL | MT |
| 2014-04-30 | 406-300-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | KALISPELL | MT |
| 2018-04-30 | 406-300-8XXX | 8000–8999 | Assigned | METROPCS, INC. | 5562 | KALISPELL | MT |
| 2020-07-02 | 406-300-9XXX | 9000–9999 | Assigned | METROPCS, INC. | 5562 | KALISPELL | MT |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.