NumberResearchThousands-blocks in 251-650
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 251-650 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 251 blocks
Most active assignees, all time — NPA 251
New assignments by month
Sep 2026
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| — | 251-650-0XXX | 0000–0999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - AL | 5255 | MOBILE | AL |
| 2003-01-30 | 251-650-1XXX | 1000–1999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - AL | 5255 | MOBILE | AL |
| 2004-03-02 | 251-650-2XXX | 2000–2999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - AL | 5255 | MOBILE | AL |
| 2023-08-07 | 251-650-3XXX | 3000–3999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - GA | 6214 | MOBILE | AL |
| 2005-10-21 | 251-650-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - AL | 5255 | MOBILE | AL |
| 2021-12-30 | 251-650-5XXX | 5000–5999 | Assigned | ONVOY, LLC - AL | 604E | MOBILE | AL |
| 2023-08-07 | 251-650-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - GA | 6214 | MOBILE | AL |
| 2021-12-30 | 251-650-7XXX | 7000–7999 | Assigned | ONVOY, LLC - AL | 604E | MOBILE | AL |
| 2023-08-07 | 251-650-8XXX | 8000–8999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - GA | 6214 | MOBILE | AL |
| 2023-08-07 | 251-650-9XXX | 9000–9999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - GA | 6214 | MOBILE | AL |
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.