NumberResearchThousands-blocks in 586-203
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 586-203 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
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2005-06-25 | 586-203-0XXX | 0000–0999 | Assigned | ACD TELECOM, INC. - MI | 3535 | MT CLEMENS | MI |
| 2004-02-25 | 586-203-1XXX | 1000–1999 | Assigned | PEERLESS NETWORK OF MICHIGAN, LLC - MI | 933G | MT CLEMENS | MI |
| 2005-06-21 | 586-203-2XXX | 2000–2999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 7279 | MT CLEMENS | MI |
| 2017-06-30 | 586-203-3XXX | 3000–3999 | Assigned | ONVOY, LLCV - MI | 543C | MT CLEMENS | MI |
| 2005-06-21 | 586-203-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 7279 | MT CLEMENS | MI |
| 2004-02-25 | 586-203-5XXX | 5000–5999 | Assigned | PEERLESS NETWORK OF MICHIGAN, LLC - MI | 933G | MT CLEMENS | MI |
| 2004-02-25 | 586-203-6XXX | 6000–6999 | Assigned | PEERLESS NETWORK OF MICHIGAN, LLC - MI | 933G | MT CLEMENS | MI |
| 2005-07-07 | 586-203-7XXX | 7000–7999 | Assigned | OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 2964 | MT CLEMENS | MI |
| — | 586-203-8XXX | 8000–8999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | MT CLEMENS | MI |
| — | 586-203-9XXX | 9000–9999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | MT CLEMENS | 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.