NumberResearchThousands-blocks in 331-757
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 331-757 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 331 blocks
Most active assignees, all time — NPA 331
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
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Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2017-04-12 | 331-757-0XXX | 0000–0999 | Assigned | TELNYX LLC | 073H | LEMONT | IL |
| 2017-06-13 | 331-757-1XXX | 1000–1999 | Assigned | ONVOY, LLC | 224C | LEMONT | IL |
| 2017-03-29 | 331-757-2XXX | 2000–2999 | Assigned | TELEPORT COMMUNICATIONS AMERICA, LLC - IL | 7136 | LEMONT | IL |
| 2017-12-18 | 331-757-3XXX | 3000–3999 | Assigned | ONVOY, LLC | 224C | LEMONT | IL |
| 2017-05-03 | 331-757-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL | 7196 | LEMONT | IL |
| 2016-08-11 | 331-757-5XXX | 5000–5999 | Assigned | COMCAST IP PHONE, LLC | 318J | LEMONT | IL |
| 2017-12-18 | 331-757-6XXX | 6000–6999 | Assigned | ONVOY, LLC | 224C | LEMONT | IL |
| 2016-10-12 | 331-757-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LEMONT | IL |
| 2016-07-13 | 331-757-8XXX | 8000–8999 | Assigned | T-MOBILE USA, INC. | 6529 | LEMONT | IL |
| 2016-07-13 | 331-757-9XXX | 9000–9999 | Assigned | T-MOBILE USA, INC. | 6529 | LEMONT | IL |
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.