NumberResearchThousands-blocks in 661-977
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 661-977 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 661 blocks
Most active assignees, all time — NPA 661
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 |
|---|---|---|---|---|---|---|---|
| — | 661-977-0XXX | 0000–0999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SNCA SGCC | CA |
| 2010-03-15 | 661-977-1XXX | 1000–1999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SNCA SGCC | CA |
| 2023-05-22 | 661-977-2XXX | 2000–2999 | Assigned | BOOST SUBSCRIBERCO L.L.C. | 490J | SNCA SGCC | CA |
| — | 661-977-3XXX | 3000–3999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SNCA SGCC | CA |
| — | 661-977-4XXX | 4000–4999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SNCA SGCC | CA |
| 2005-09-26 | 661-977-5XXX | 5000–5999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA | 7240 | SNCA SGCC | CA |
| 2013-12-09 | 661-977-6XXX | 6000–6999 | Assigned | BANDWIDTH.COM CLEC, LLC - CA | 981E | SNCA SGCC | CA |
| 2018-07-09 | 661-977-7XXX | 7000–7999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | SNCA SGCC | CA |
| 2012-12-04 | 661-977-8XXX | 8000–8999 | Assigned | ONVOY, LLC - CA | 649C | SNCA SGCC | CA |
| — | 661-977-9XXX | 9000–9999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - CA | 8826 | SNCA SGCC | 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.