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 |
|---|---|---|---|---|---|---|
| 2012-07-17 | 518-660 | 0–9 XXXall 10 · 6 holders which blocks → | AT&T - LOCAL | 7421 | HUDSON | NY |
| — | 518-306 | 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | AT&T - LOCAL | 7421 | SARATOGSPG | NY |
| — | 518-951 | 0XXX3XXX4XXX5XXX6XXX8XXX9XXX · 2 holders which blocks → | AT&T - LOCAL | 7421 | COLONIE | NY |
| — | 518-952 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → | AT&T - LOCAL | 7421 | SCHENCTADY | NY |
| — | 518-953 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | AT&T - LOCAL | 7421 | TROY | NY |
| — | 518-954 | 0XXX1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | AT&T - LOCAL | 7421 | AMSTERDAM | NY |
| — | 518-955 | 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | AT&T - LOCAL | 7421 | GLENSFALLS | NY |
| — | 518-956 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | AT&T - LOCAL | 7421 | ALBANY | NY |
| — | 518-957 | 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | AT&T - LOCAL | 7421 | PLATTSBG | NY |
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.