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 |
|---|---|---|---|---|---|---|
| 2001-03-08 | 617-944 | 0–9 XXXall 10 · 4 holders which blocks → | COMCAST IP PHONE, LLC | 318J | EVERETT | MA |
| — | 617-207 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → | COMCAST IP PHONE, LLC | 318J | WINTHROP | MA |
| — | 617-294 | 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | COMCAST IP PHONE, LLC | 318J | EVERETT | MA |
| — | 617-322 | 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → | COMCAST IP PHONE, LLC | 318J | MILTON | MA |
| — | 617-466 | 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | COMCAST IP PHONE, LLC | 318J | CHELSEA | MA |
| — | 617-481 | 3XXX4XXX6XXX7XXX8XXX · 2 holders which blocks → | COMCAST IP PHONE, LLC | 318J | QUINCY | MA |
| — | 617-744 | 2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | COMCAST IP PHONE, LLC | 318J | WATERTOWN | MA |
| — | 617-764 | 3XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → | COMCAST IP PHONE, LLC | 318J | SOMERVILLE | MA |
| — | 617-910 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → | COMCAST IP PHONE, LLC | 318J | HYDE PARK | MA |
| — | 617-916 | 3XXX4XXX6XXX7XXX8XXX which blocks → | COMCAST IP PHONE, LLC | 318J | NEWTON | MA |
| — | 617-945 | 3XXX4XXX6XXX8XXX · 2 holders which blocks → | COMCAST IP PHONE, LLC | 318J | CAMBRIDGE | MA |
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.