NumberResearchThousands-blocks in 909-331
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 909-331 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 909 blocks
Most active assignees, all time — NPA 909
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 |
|---|---|---|---|---|---|---|---|
| 2004-04-27 | 909-331-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA | 6006 | ONTARIO | CA |
| 2002-11-08 | 909-331-1XXX | 1000–1999 | Assigned | T-MOBILE USA, INC. | 6529 | ONTARIO | CA |
| 2002-11-08 | 909-331-2XXX | 2000–2999 | Assigned | T-MOBILE USA, INC. | 6529 | ONTARIO | CA |
| — | 909-331-3XXX | 3000–3999 | Reserved | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 7229 | ONTARIO | CA |
| 2001-03-26 | 909-331-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 7229 | ONTARIO | CA |
| 2002-11-08 | 909-331-5XXX | 5000–5999 | Assigned | T-MOBILE USA, INC. | 6529 | ONTARIO | CA |
| 2003-07-03 | 909-331-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | ONTARIO | CA |
| 2002-11-08 | 909-331-7XXX | 7000–7999 | Assigned | T-MOBILE USA, INC. | 6529 | ONTARIO | CA |
| 2002-11-08 | 909-331-8XXX | 8000–8999 | Assigned | T-MOBILE USA, INC. | 6529 | ONTARIO | CA |
| 2002-11-08 | 909-331-9XXX | 9000–9999 | Assigned | T-MOBILE USA, INC. | 6529 | ONTARIO | 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.