NumberResearchThousands-blocks in 818-583
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 818-583 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 818 blocks
Most active assignees, all time — NPA 818
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 |
|---|---|---|---|---|---|---|---|
| 2013-02-27 | 818-583-0XXX | 0000–0999 | Assigned | ONVOY, LLC - CA | 649C | PSDN LACN | CA |
| 2002-01-08 | 818-583-1XXX | 1000–1999 | Assigned | PAETEC ITEL, LLC | 829J | PSDN LACN | CA |
| 2003-09-23 | 818-583-2XXX | 2000–2999 | Assigned | IP HORIZON LLC | 515J | PSDN LACN | CA |
| 2003-09-23 | 818-583-3XXX | 3000–3999 | Assigned | IP HORIZON LLC | 515J | PSDN LACN | CA |
| 2006-03-02 | 818-583-4XXX | 4000–4999 | Assigned | U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | 671J | PSDN LACN | CA |
| 2006-06-07 | 818-583-5XXX | 5000–5999 | Assigned | UTILITY TELECOM GROUP, LLC - CA | 9262 | PSDN LACN | CA |
| 2010-02-23 | 818-583-6XXX | 6000–6999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | PSDN LACN | CA |
| 2011-01-24 | 818-583-7XXX | 7000–7999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | PSDN LACN | CA |
| 2010-02-11 | 818-583-8XXX | 8000–8999 | Assigned | ONVOY, LLC - CA | 649C | PSDN LACN | CA |
| — | 818-583-9XXX | 9000–9999 | Reserved | TELEPORT COMMUNICATIONS AMERICA, LLC - CA | 7139 | PSDN LACN | CA |
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.