NumberResearchThousands-blocks in 586-540
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 586-540 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 586 blocks
Most active assignees, all time — NPA 586
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 |
|---|---|---|---|---|---|---|---|
| 2025-06-16 | 586-540-0XXX | 0000–0999 | Assigned | TERRA NOVA TELECOM INC. | 145J | ROMEO | MI |
| — | 586-540-1XXX | 1000–1999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | ROMEO | MI |
| 2021-09-16 | 586-540-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 6003 | ROMEO | MI |
| 2005-11-09 | 586-540-3XXX | 3000–3999 | Assigned | ACD TELECOM, INC. - MI | 3535 | ROMEO | MI |
| — | 586-540-4XXX | 4000–4999 | Available | ROMEO | MI | ||
| 2021-09-21 | 586-540-5XXX | 5000–5999 | Assigned | ONVOY SPECTRUM, LLC | 624H | ROMEO | MI |
| 2009-10-21 | 586-540-6XXX | 6000–6999 | Assigned | CLEAR RATE COMMUNICATIONS, LLC | 046L | ROMEO | MI |
| 2006-10-06 | 586-540-7XXX | 7000–7999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 6003 | ROMEO | MI |
| 2005-01-20 | 586-540-8XXX | 8000–8999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 7279 | ROMEO | MI |
| 2025-09-05 | 586-540-9XXX | 9000–9999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | ROMEO | MI |
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.