NumberResearchThousands-blocks in 520-350
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 520-350 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 520 blocks
Most active assignees, all time — NPA 520
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 |
|---|---|---|---|---|---|---|---|
| 2009-09-02 | 520-350-0XXX | 0000–0999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | CASAGRANDE | AZ |
| 2008-05-19 | 520-350-1XXX | 1000–1999 | Assigned | GILA LOCAL EXCHANGE CARRIER, INC. - AZ | 947E | CASAGRANDE | AZ |
| 2009-08-19 | 520-350-2XXX | 2000–2999 | Assigned | GILA LOCAL EXCHANGE CARRIER, INC. - AZ | 947E | CASAGRANDE | AZ |
| 2009-09-02 | 520-350-3XXX | 3000–3999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | CASAGRANDE | AZ |
| 2009-09-02 | 520-350-4XXX | 4000–4999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | CASAGRANDE | AZ |
| 2009-09-02 | 520-350-5XXX | 5000–5999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | CASAGRANDE | AZ |
| 2009-11-12 | 520-350-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | CASAGRANDE | AZ |
| 2009-04-24 | 520-350-7XXX | 7000–7999 | Assigned | ONVOY, LLC - AZ | 630E | CASAGRANDE | AZ |
| 2009-11-12 | 520-350-8XXX | 8000–8999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | CASAGRANDE | AZ |
| 2010-07-14 | 520-350-9XXX | 9000–9999 | Assigned | ONVOY, LLC - AZ | 630E | CASAGRANDE | AZ |
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.