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 |
|---|---|---|---|---|---|---|
| — | 586-958 | not yet reported which blocks → | MI | |||
| — | 586-959 | not yet reported which blocks → | MI | |||
| — | 586-960 | 3XXX4XXX5XXX6XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | ROMEO | MI |
| — | 586-961 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 6003 | MT CLEMENS | MI |
| — | 586-974 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | WARREN | MI |
| — | 586-975 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | MT CLEMENS | MI |
| — | 586-976 | not yet reported which blocks → | MI | |||
| — | 586-977 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | WARREN | MI |
| — | 586-978 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | WARREN | MI |
| — | 586-979 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | WARREN | MI |
| — | 586-980 | 6XXX which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 6003 | MT CLEMENS | MI |
| — | 586-981 | 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | WARREN | MI |
| — | 586-983 | 6XXX8XXX9XXX · 3 holders which blocks → | MICHIGAN BELL TEL CO | 9323 | WARREN | MI |
| — | 586-986 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | CENTERLINE | MI |
| — | 586-988 | not yet reported which blocks → | MI | |||
| — | 586-989 | not yet reported which blocks → | MI | |||
| — | 586-994 | 7XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-995 | 7XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-996 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-997 | 7XXX8XXX · 2 holders which blocks → | MICHIGAN BELL TEL CO | 9323 | UTICA | MI |
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.