NumberResearchRecent thousands-block assignments
0 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/20/2026
Most carrier growth happens here, not at the prefix level: under number pooling, carriers receive individual 1,000-number blocks (e.g. 626-470-0XXX) within already-assigned prefixes. Assignments are initial assignments — the current serving carrier of individual numbers may differ due to portability.
Most active assignees, all time — NPA 424
New assignments by month
Sep 2026
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| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2016-11-01 | 424-541-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | INGLEWOOD | CA |
| 2015-05-13 | 424-376-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | TORRANCE | CA |
| 2015-01-09 | 424-381-4XXX | 4000–4999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CMTN CMTN | CA |
| 2014-10-30 | 424-364-0XXX | 0000–0999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SAN PEDRO | CA |
| 2014-10-09 | 424-351-8XXX | 8000–8999 | Assigned | AT&T ENTERPRISES, LLC | 516C | INGLEWOOD | CA |
| 2014-09-11 | 424-361-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CULVERCITY | CA |
| 2014-07-22 | 424-347-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LOMITA | CA |
| 2014-06-19 | 424-338-6XXX | 6000–6999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CMTN CMTN | CA |
| 2014-06-12 | 424-348-8XXX | 8000–8999 | Assigned | AT&T ENTERPRISES, LLC | 516C | HAWTHORNE | CA |
| 2014-03-31 | 424-329-3XXX | 3000–3999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CMTN GRDN | CA |
| 2014-01-28 | 424-335-0XXX | 0000–0999 | Assigned | AT&T ENTERPRISES, LLC | 516C | BEVERLYHLS | CA |
| 2013-10-01 | 424-287-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SAN PEDRO | CA |
| 2013-07-17 | 424-331-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | INGLEWOOD | CA |
| 2013-06-13 | 424-296-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CMTN CMTN | CA |
| 2009-12-14 | 424-738-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | AVALON | CA |
| 2006-06-21 | 424-603-4XXX | 4000–4999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CULVERCITY | CA |
| 2006-03-23 | 424-263-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LOMITA | CA |
| 2006-03-23 | 424-264-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SAN PEDRO | CA |
| 2006-03-23 | 424-558-3XXX | 3000–3999 | Assigned | AT&T ENTERPRISES, LLC | 516C | TORRANCE | CA |
| 2006-03-23 | 424-675-4XXX | 4000–4999 | Assigned | AT&T ENTERPRISES, LLC | 516C | HAWTHORNE | CA |
| 2006-03-23 | 424-702-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | INGLEWOOD | 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.