NumberResearchThousands-blocks in 574-821
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 574-821 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 574 blocks
Most active assignees, all time — NPA 574
New assignments by month
Sep 2026
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| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| — | 574-821-0XXX | 0000–0999 | Reserved | FRONTIER NORTH, INC.. - IN | 0772 | MIDDLEBURY | IN |
| — | 574-821-1XXX | 1000–1999 | Reserved | FRONTIER NORTH, INC.. - IN | 0772 | MIDDLEBURY | IN |
| 2019-08-12 | 574-821-2XXX | 2000–2999 | Assigned | PEERLESS NETWORK OF INDIANA, LLC - IN | 279F | MIDDLEBURY | IN |
| 2025-06-06 | 574-821-3XXX | 3000–3999 | Assigned | TWILIO INTERNATIONAL, INC. | 506J | MIDDLEBURY | IN |
| 2005-03-08 | 574-821-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - IN | 4803 | MIDDLEBURY | IN |
| 2020-04-16 | 574-821-5XXX | 5000–5999 | Assigned | ONVOY, LLC - IN | 097D | MIDDLEBURY | IN |
| 2020-04-16 | 574-821-6XXX | 6000–6999 | Assigned | ONVOY, LLC - IN | 097D | MIDDLEBURY | IN |
| 2021-02-24 | 574-821-7XXX | 7000–7999 | Assigned | ONVOY, LLC - IN | 097D | MIDDLEBURY | IN |
| 2020-06-15 | 574-821-8XXX | 8000–8999 | Assigned | TELNYX LLC | 073H | MIDDLEBURY | IN |
| 2015-09-21 | 574-821-9XXX | 9000–9999 | Assigned | PEERLESS NETWORK OF INDIANA, LLC - IN | 279F | MIDDLEBURY | IN |
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.