NumberResearchThousands-blocks in 423-375
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 423-375 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 423 blocks
Most active assignees, all time — NPA 423
New assignments by month
Sep 2026
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2012-09-24 | 423-375-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | BENTON | TN |
| 2015-08-12 | 423-375-1XXX | 1000–1999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | BENTON | TN |
| 2012-08-06 | 423-375-2XXX | 2000–2999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | BENTON | TN |
| 2016-12-05 | 423-375-3XXX | 3000–3999 | Assigned | PAETEC ITEL, LLC | 829J | BENTON | TN |
| 2016-02-29 | 423-375-4XXX | 4000–4999 | Assigned | ONVOY, LLC - TN | 525E | BENTON | TN |
| 2010-03-18 | 423-375-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | BENTON | TN |
| 2024-03-13 | 423-375-6XXX | 6000–6999 | Assigned | TWIN LAKES COMMUNICATIONS, INC. - TN | 204G | BENTON | TN |
| 2026-08-20 | 423-375-7XXX | 7000–7999 | Assigned | OPENTACT INC. | 824J | BENTON | TN |
| 2016-02-29 | 423-375-8XXX | 8000–8999 | Assigned | ONVOY, LLC - TN | 525E | BENTON | TN |
| 2014-10-28 | 423-375-9XXX | 9000–9999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | BENTON | TN |
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.