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 323
New assignments by month
Sep 2026
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2016-09-21 | 323-713-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 09 | CA |
| 2015-06-11 | 323-421-6XXX | 6000–6999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 12 | CA |
| 2015-04-01 | 323-553-6XXX | 6000–6999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 06 | CA |
| 2015-02-27 | 323-208-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 09 | CA |
| 2015-01-09 | 323-676-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 08 | CA |
| 2014-11-07 | 323-675-1XXX | 1000–1999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 03 | CA |
| 2014-10-02 | 323-870-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 11 | CA |
| 2014-09-17 | 323-943-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 05 | CA |
| 2014-08-14 | 323-553-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 06 | CA |
| 2014-08-14 | 323-745-0XXX | 0000–0999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 14 | CA |
| 2014-07-01 | 323-531-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 09 | CA |
| 2014-06-06 | 323-746-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 13 | CA |
| 2014-04-14 | 323-741-8XXX | 8000–8999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 02 | CA |
| 2013-12-13 | 323-484-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 06 | CA |
| 2013-10-09 | 323-389-8XXX | 8000–8999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 12 | CA |
| 2013-10-01 | 323-531-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 09 | CA |
| 2013-07-17 | 323-498-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 14 | CA |
| 2010-12-28 | 323-879-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 13 | CA |
| 2006-06-09 | 323-406-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 05 | CA |
| 2006-06-09 | 323-476-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 06 | CA |
| 2006-06-09 | 323-505-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 04 | CA |
| 2006-03-31 | 323-645-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 14 | CA |
| 2006-02-06 | 323-325-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 08 | CA |
| 2006-02-06 | 323-643-4XXX | 4000–4999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 11 | CA |
| 2006-02-06 | 323-696-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 09 | CA |
| 2006-02-06 | 323-792-4XXX | 4000–4999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 12 | CA |
| 2006-02-06 | 323-928-2XXX | 2000–2999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 02 | CA |
| 2006-02-06 | 323-999-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 03 | CA |
| 2006-01-26 | 323-424-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | LSAN DA 13 | CA |
| 2005-03-25 | 323-490-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | MONTEBELLO | 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.