NumberResearchThousands-blocks in 336-617
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/20/2026
The ten 1,000-number thousand-blocks inside prefix 336-617 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 336 blocks
Most active assignees, all time — NPA 336
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
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Jan 2026
Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2009-03-04 | 336-617-0XXX | 0000–0999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2012-05-14 | 336-617-1XXX | 1000–1999 | Assigned | SUNCOM DBA T-MOBILE USA | 8645 | GREENSBORO | NC |
| 2004-07-13 | 336-617-2XXX | 2000–2999 | Assigned | LEVEL 3 TELECOM OF NORTH CAROLINA, LP - NC | 7973 | GREENSBORO | NC |
| 2006-09-11 | 336-617-3XXX | 3000–3999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2006-09-11 | 336-617-4XXX | 4000–4999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2006-09-11 | 336-617-5XXX | 5000–5999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2006-09-11 | 336-617-6XXX | 6000–6999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2008-05-27 | 336-617-7XXX | 7000–7999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2008-05-27 | 336-617-8XXX | 8000–8999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | GREENSBORO | NC |
| 2010-10-13 | 336-617-9XXX | 9000–9999 | Assigned | BANDWIDTH.COM CLEC, LLC - NC | 998E | GREENSBORO | NC |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.