NumberResearchThousands-blocks in 351-356
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/19/2026
The ten 1,000-number thousand-blocks inside prefix 351-356 and who was initially assigned each. Under pooling these blocks often belong to different carriers — the single prefix-level “assignee” is usually just the pool / code holder, not who holds the numbers. ← all 351 blocks
Most active assignees, all time — NPA 351
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
Mar 2026
Feb 2026
Jan 2026
Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2021-02-02 | 351-356-0XXX | 0000–0999 | Assigned | TELNYX LLC | 073H | LEOMINSTER | MA |
| 2021-03-23 | 351-356-1XXX | 1000–1999 | Assigned | ONVOY, LLC - MA | 892D | LEOMINSTER | MA |
| 2021-03-23 | 351-356-2XXX | 2000–2999 | Assigned | ONVOY, LLC - MA | 892D | LEOMINSTER | MA |
| 2024-08-20 | 351-356-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | 6387 | LEOMINSTER | MA |
| 2020-07-27 | 351-356-4XXX | 4000–4999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | LEOMINSTER | MA |
| — | 351-356-5XXX | 5000–5999 | Available | LEOMINSTER | MA | ||
| 2020-07-27 | 351-356-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | LEOMINSTER | MA |
| 2020-07-22 | 351-356-7XXX | 7000–7999 | Assigned | FRACTEL, LLC | 965H | LEOMINSTER | MA |
| 2021-03-10 | 351-356-8XXX | 8000–8999 | Assigned | ONVOY SPECTRUM, LLC | 624H | LEOMINSTER | MA |
| 2020-07-22 | 351-356-9XXX | 9000–9999 | Assigned | FRACTEL, LLC | 965H | LEOMINSTER | MA |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.