NumberResearchThousands-blocks in 256-373
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 256-373 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 256 blocks
Most active assignees, all time — NPA 256
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 |
|---|---|---|---|---|---|---|---|
| — | 256-373-0XXX | 0000–0999 | Reserved | TELEPORT COMMUNICATIONS AMERICA, LLC - AL | 8271 | DADEVILLE | AL |
| 2005-06-08 | 256-373-1XXX | 1000–1999 | Assigned | SOUTHERN COMMUNICATIONS SERVICES, INC. | 6744 | DADEVILLE | AL |
| 2010-10-05 | 256-373-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | DADEVILLE | AL |
| 2012-04-30 | 256-373-3XXX | 3000–3999 | Assigned | CHARTER IP ENABLED SERVICES, LLC | 792K | DADEVILLE | AL |
| 2019-04-05 | 256-373-4XXX | 4000–4999 | Assigned | CORETEL ALABAMA, INC. - AL | 476F | DADEVILLE | AL |
| 2004-05-19 | 256-373-5XXX | 5000–5999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - AL | 5255 | DADEVILLE | AL |
| 2019-04-05 | 256-373-6XXX | 6000–6999 | Assigned | CORETEL ALABAMA, INC. - AL | 476F | DADEVILLE | AL |
| 2013-09-24 | 256-373-7XXX | 7000–7999 | Assigned | PAETEC ITEL, LLC | 829J | DADEVILLE | AL |
| 2017-08-23 | 256-373-8XXX | 8000–8999 | Assigned | TELNYX LLC | 073H | DADEVILLE | AL |
| 2026-04-13 | 256-373-9XXX | 9000–9999 | Assigned | BANDWIDTH.COM CLEC, LLC - AL | 072F | DADEVILLE | AL |
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.