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 |
|---|---|---|---|---|---|---|
| 2002-04-25 | 503-459 | 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | PORTLAND | OR |
| — | 503-416 | not yet reported which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | PORTLAND | OR |
| — | 503-479 | 0XXX2XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | CLACKAMAS | OR |
| — | 503-482 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | STFRD-SNDY | OR |
| — | 503-488 | 0XXX5XXX6XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | PORTLAND | OR |
| — | 503-512 | 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | GRESHAM | OR |
| — | 503-592 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | CANBYNEEDY | OR |
| — | 503-608 | 0XXX2XXX4XXX7XXX8XXX9XXX · 2 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | BEAVERTON | OR |
| — | 503-732 | 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | BEAVER CRK | OR |
| — | 503-734 | 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | PORTLAND | OR |
| — | 503-770 | 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | CHARBONNEU | OR |
| — | 503-773 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | NORTH PL | OR |
| — | 503-776 | 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | AURORA | OR |
| — | 503-840 | 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | BEAVERTON | OR |
| — | 503-850 | 0XXX2XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | CLACKAMAS | OR |
| — | 503-855 | 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | STFRD-SNDY | OR |
| — | 503-857 | 0XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | MCMINNVL | OR |
| — | 503-858 | 0XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | BEAVERTON | OR |
| — | 503-862 | 0XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | SHERWOOD | OR |
| — | 503-882 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | CLACKAMAS | OR |
| — | 503-899 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | NEWBERG | OR |
| — | 503-941 | 0XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → | LEVEL 3 TELECOM OF OREGON, LLC - OR | 7537 | BEAVERTON | OR |
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.