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 |
|---|---|---|---|---|---|---|
| 2006-12-14 | 513-746 | 0–9 XXXall 10 · 2 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CINCINNATI | OH |
| 2006-08-21 | 513-878 | 0–9 XXXall 10 · 4 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CINCINNATI | OH |
| 2001-12-20 | 513-261 | 7XXX8XXX9XXX which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | MIDDLETOWN | OH |
| — | 513-338 | 3XXX4XXX6XXX7XXX9XXX · 2 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CINCINNATI | OH |
| — | 513-354 | 0XXX9XXX · 2 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CINCINNATI | OH |
| — | 513-492 | 0XXX1XXX2XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | MASON | OH |
| — | 513-618 | not yet reported which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CINCINNATI | OH |
| — | 513-619 | 0XXX which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CINCINNATI | OH |
| — | 513-644 | 0XXX2XXX3XXX5XXX6XXX9XXX · 5 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | BETHANY | OH |
| — | 513-645 | 3XXX6XXX7XXX · 2 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | HAMILTON | OH |
| — | 513-685 | 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | CLERMONT | OH |
| — | 513-695 | not yet reported which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | LEBANON | OH |
| — | 513-696 | 2XXX6XXX7XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | LEBANON | OH |
| — | 513-701 | 8XXX9XXX · 2 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | MASON | OH |
| — | 513-707 | 2XXX8XXX which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | LTL MIAMI | OH |
| — | 513-788 | 1XXX2XXX3XXX4XXX6XXX7XXX8XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OHIO, LLC - OH | 7460 | HARRISON | OH |
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.