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 |
|---|---|---|---|---|---|---|
| 2014-04-09 | 857-377 | 0–9 XXXwhole prefix which blocks → | PAETEC ITEL, LLC | 829J | BOSTON | MA |
| 2012-08-16 | 857-285 | 0–9 XXXall 10 · 5 holders which blocks → | PAETEC ITEL, LLC | 829J | CAMBRIDGE | MA |
| 2011-10-03 | 857-213 | 0–9 XXXwhole prefix which blocks → | PAETEC ITEL, LLC | 829J | BOSTON | MA |
| 2011-08-02 | 857-368 | 0–9 XXXwhole prefix which blocks → | PAETEC ITEL, LLC | 829J | BOSTON | MA |
| 2010-02-15 | 857-293 | 0–9 XXXall 10 · 5 holders which blocks → | PAETEC ITEL, LLC | 829J | EASTBOSTON | MA |
| 2001-07-12 | 857-228 | 0–9 XXXall 10 · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | WATERTOWN | MA |
| 2001-04-23 | 857-252 | 1XXX which blocks → | PAETEC ITEL, LLC | 829J | QUINCY | MA |
| 2001-04-23 | 857-253 | 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | CAMBRIDGE | MA |
| 2001-04-23 | 857-254 | 1XXX8XXX9XXX · 2 holders which blocks → | PAETEC ITEL, LLC | 829J | BOSTON | MA |
| 2001-04-23 | 857-255 | 1XXX9XXX which blocks → | PAETEC ITEL, LLC | 829J | NEWTON | MA |
| 2001-03-20 | 857-220 | 7XXX8XXX9XXX which blocks → | PAETEC ITEL, LLC | 829J | DORCHESTER | MA |
| 2001-03-20 | 857-364 | 0–9 XXXall 10 · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | BROOKLINE | MA |
| 2001-03-20 | 857-373 | 7XXX8XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | BELMONT | MA |
| 2001-03-20 | 857-401 | 7XXX8XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | SO BOSTON | MA |
| 2001-03-20 | 857-403 | 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | QUINCY | MA |
| 2001-03-20 | 857-547 | 7XXX8XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | JAMAICA PL | MA |
| 2001-03-20 | 857-574 | 0–9 XXXall 10 · 6 holders which blocks → | PAETEC ITEL, LLC | 829J | EASTBOSTON | MA |
| — | 857-223 | none assigned yet which blocks → | PAETEC ITEL, LLC | 829J | BOSTON | MA |
| — | 857-229 | 0–9 XXXall 10 · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | NEWTON | MA |
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.