NumberResearchRecent thousands-block assignments
0 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/19/2026
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 951
New assignments by month
Sep 2026
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2017-01-17 | 951-433-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | TEMSCL CNY | CA |
| 2016-10-12 | 951-602-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | ARLINGTON | CA |
| 2015-09-03 | 951-475-1XXX | 1000–1999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2015-05-14 | 951-429-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | WOODCREST | CA |
| 2015-05-13 | 951-772-0XXX | 0000–0999 | Assigned | AT&T ENTERPRISES, LLC | 516C | ARLINGTON | CA |
| 2015-04-09 | 951-456-0XXX | 0000–0999 | Assigned | AT&T ENTERPRISES, LLC | 516C | MIRA LOMA | CA |
| 2014-08-06 | 951-394-8XXX | 8000–8999 | Assigned | AT&T ENTERPRISES, LLC | 516C | RIVERSIDE | CA |
| 2014-07-09 | 951-432-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2011-08-19 | 951-299-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | ARLINGTON | CA |
| 2011-07-15 | 951-356-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2010-09-09 | 951-893-1XXX | 1000–1999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2010-08-04 | 951-289-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | RIVERSIDE | CA |
| 2010-03-25 | 951-427-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2010-03-11 | 951-525-3XXX | 3000–3999 | Assigned | AT&T ENTERPRISES, LLC | 516C | ARLINGTON | CA |
| 2009-10-12 | 951-268-6XXX | 6000–6999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2007-08-09 | 951-934-3XXX | 3000–3999 | Assigned | AT&T ENTERPRISES, LLC | 516C | MIRA LOMA | CA |
| 2006-06-22 | 951-427-3XXX | 3000–3999 | Assigned | AT&T ENTERPRISES, LLC | 516C | CORONA | CA |
| 2006-03-09 | 951-638-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | TEMSCL CNY | CA |
| 2006-03-09 | 951-729-6XXX | 6000–6999 | Assigned | AT&T ENTERPRISES, LLC | 516C | ARLINGTON | CA |
| 2006-03-09 | 951-742-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | RIVERSIDE | CA |
| 2006-02-06 | 951-776-8XXX | 8000–8999 | Assigned | AT&T ENTERPRISES, LLC | 516C | WOODCREST | CA |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.