NumberResearchThousands-blocks in 530-728
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/19/2026
The ten 1,000-number thousand-blocks inside prefix 530-728 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 530 blocks
Most active assignees, all time — NPA 530
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
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Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2015-04-27 | 530-728-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | GRVY SOUTH | CA |
| 2021-07-14 | 530-728-1XXX | 1000–1999 | Assigned | ONVOY, LLC - CA | 649C | GRVY SOUTH | CA |
| 2019-01-28 | 530-728-2XXX | 2000–2999 | Assigned | ONVOY, LLC - CA | 649C | GRVY SOUTH | CA |
| 2014-02-11 | 530-728-3XXX | 3000–3999 | Assigned | CSC VOICE, LLC | 612K | GRVY SOUTH | CA |
| — | 530-728-4XXX | 4000–4999 | Available | GRVY SOUTH | CA | ||
| 2021-06-23 | 530-728-5XXX | 5000–5999 | Assigned | ONVOY, LLC - CA | 649C | GRVY SOUTH | CA |
| 2021-06-23 | 530-728-6XXX | 6000–6999 | Assigned | ONVOY, LLC - CA | 649C | GRVY SOUTH | CA |
| — | 530-728-7XXX | 7000–7999 | Available | GRVY SOUTH | CA | ||
| 2019-01-28 | 530-728-8XXX | 8000–8999 | Assigned | ONVOY, LLC - CA | 649C | GRVY SOUTH | CA |
| 2021-05-04 | 530-728-9XXX | 9000–9999 | Assigned | PEERLESS NETWORK OF CALIFORNIA, LLC - CA | 373F | GRVY SOUTH | CA |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.