NumberResearchThousands-blocks in 603-338
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 603-338 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 603 blocks
Most active assignees, all time — NPA 603
New assignments by month
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2015-08-27 | 603-338-0XXX | 0000–0999 | Assigned | TWC IP ENABLED SERVICES, LLC | 793K | KEENE | NH |
| 2021-09-02 | 603-338-1XXX | 1000–1999 | Assigned | OMNIPOINT MIAMI E LICENSE, LLC | 6889 | KEENE | NH |
| 2022-09-08 | 603-338-2XXX | 2000–2999 | Assigned | TELNYX LLC | 073H | KEENE | NH |
| 2023-03-08 | 603-338-3XXX | 3000–3999 | Assigned | ONVOY, LLC - NH | 637E | KEENE | NH |
| 2002-09-07 | 603-338-4XXX | 4000–4999 | Assigned | OTEL TELEKOM, INC. - NH | 9827 | KEENE | NH |
| 2004-01-16 | 603-338-5XXX | 5000–5999 | Assigned | TELEPORT COMMUNICATIONS AMERICA, LLC - NH | 8299 | KEENE | NH |
| 2022-10-31 | 603-338-6XXX | 6000–6999 | Assigned | ONVOY, LLC - NH | 637E | KEENE | NH |
| 2016-03-25 | 603-338-7XXX | 7000–7999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | KEENE | NH |
| 2015-01-29 | 603-338-8XXX | 8000–8999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | KEENE | NH |
| — | 603-338-9XXX | 9000–9999 | Reserved | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH | 7778 | KEENE | NH |
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.