Recent prefix assignments
347 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/29/2026
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 |
|---|---|---|---|---|---|---|
| — | 586-349 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | MT CLEMENS | MI |
| — | 586-350 | 0XXX2XXX · 2 holders which blocks → | METROPCS, INC. | 5562 | ROSEVILLE | MI |
| — | 586-353 | 5XXX8XXX which blocks → | PAETEC ITEL, LLC | 829J | CENTERLINE | MI |
| — | 586-354 | 0–9 XXXall 10 · 3 holders which blocks → | 123.NET, LLC | 2550 | WARREN | MI |
| — | 586-360 | 0XXX1XXX2XXX9XXX · 4 holders which blocks → | METROPCS, INC. | 5562 | ROSEVILLE | MI |
| — | 586-361 | not yet reported which blocks → | SPOK, INC. | 6630 | ROMEO | MI |
| — | 586-362 | 0XXX1XXX2XXX3XXX7XXX8XXX9XXX · 6 holders which blocks → | METROPCS, INC. | 5562 | ROSEVILLE | MI |
| — | 586-363 | not yet reported which blocks → | SPOK, INC. | 6630 | MT CLEMENS | MI |
| — | 586-372 | 0–9 XXXall 10 · 6 holders which blocks → | OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 2964 | ROMEO | MI |
| — | 586-380 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | ROMEO | MI |
| — | 586-381 | 5XXX7XXX · 2 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-382 | 9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-383 | 9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-393 | 0XXX2XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | AT&T ENTERPRISES, LLC | 516C | CENTERLINE | MI |
| — | 586-402 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | WARREN | MI |
| — | 586-403 | not yet reported which blocks → | SPOK, INC. | 6630 | MT CLEMENS | MI |
| — | 586-405 | none assigned yet which blocks → | OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 2964 | MT CLEMENS | MI |
| — | 586-406 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | WARREN | MI |
| — | 586-408 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | MT CLEMENS | MI |
| — | 586-409 | not yet reported which blocks → | SPOK, INC. | 6630 | MT CLEMENS | MI |
| — | 586-411 | not yet reported which blocks → | MULTIPLE OCN LISTING | MULT | XXXXXXXXXX | MI |
| — | 586-412 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
| — | 586-413 | 7XXX9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-415 | none assigned yet which blocks → | MICHIGAN BELL TEL CO | 9323 | ROSEVILLE | MI |
| — | 586-416 | 9XXX which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
| — | 586-418 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | WARREN | MI |
| — | 586-419 | not yet reported which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 6003 | MT CLEMENS | MI |
| — | 586-420 | 0XXX1XXX2XXX7XXX8XXX · 3 holders which blocks → | METROPCS, INC. | 5562 | ROSEVILLE | MI |
| — | 586-421 | 4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
| — | 586-427 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | CENTERLINE | MI |
| — | 586-430 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - MI | 770E | RICHMOND | MI |
| — | 586-431 | 6XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-435 | 4XXX9XXX · 2 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | ROSEVILLE | MI |
| — | 586-436 | 2XXX3XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-438 | 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-439 | 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 7279 | ROSEVILLE | MI |
| — | 586-443 | 0XXX1XXX3XXX6XXX8XXX9XXX which blocks → | MICHIGAN BELL TEL CO | 9323 | ROSEVILLE | MI |
| — | 586-445 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | ROSEVILLE | MI |
| — | 586-446 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | WARREN | MI |
| — | 586-447 | 2XXX6XXX7XXX · 2 holders which blocks → | MICHIGAN BELL TEL CO | 9323 | ROSEVILLE | MI |
| — | 586-450 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | MT CLEMENS | MI |
| — | 586-451 | not yet reported which blocks → | AMERICAN MESSAGING SERVICES, LLC | 9748 | ROSEVILLE | MI |
| — | 586-457 | 2XXX3XXX5XXX6XXX7XXX8XXX9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | WARREN | MI |
| — | 586-461 | 7XXX8XXX9XXX · 2 holders which blocks → | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 7279 | MT CLEMENS | MI |
| — | 586-463 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
| — | 586-464 | 7XXX which blocks → | PAETEC ITEL, LLC | 829J | MT CLEMENS | MI |
| — | 586-465 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
| — | 586-466 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
| — | 586-467 | 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 7279 | CENTERLINE | MI |
| — | 586-468 | not yet reported which blocks → | MICHIGAN BELL TEL CO | 9323 | MT CLEMENS | MI |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/29/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.