NumberResearchRecent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026
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 |
|---|---|---|---|---|---|---|
| — | 231-613 | 1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | SCOTTVILLE | MI |
| — | 231-620 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-632 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-633 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-645 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-709 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-715 | 1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 7 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-730 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | MUSKEGON | MI |
| — | 231-742 | 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | HART | MI |
| — | 231-750 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | MUSKEGON | MI |
| — | 231-818 | 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | CHEBOYGAN | MI |
| — | 231-852 | 1XXX3XXX8XXX9XXX · 2 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | LUDINGTON | MI |
| — | 231-855 | 4XXX5XXX6XXX7XXX8XXX9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | MUSKEGON | MI |
| — | 231-871 | 1XXX3XXX6XXX8XXX9XXX · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | BEULAH | MI |
| — | 231-872 | 2XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | REED CITY | MI |
| — | 231-881 | 8XXX9XXX · 2 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | PETOSKEY | MI |
| — | 231-883 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | TRAVERSECY | MI |
| — | 231-884 | 3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | CADILLAC | MI |
| — | 231-886 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | KALKASKA | MI |
| — | 231-887 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | MANISTEE | MI |
| — | 231-920 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | CADILLAC | MI |
| — | 231-955 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | MUSKEGON | MI |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.