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 551
New assignments by month
Sep 2026
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2020-04-29 | 551-221-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | BAYONNE | NJ |
| 2020-04-29 | 551-282-5XXX | 5000–5999 | Assigned | IP HORIZON LLC | 515J | WESTWOOD | NJ |
| 2020-04-29 | 551-282-6XXX | 6000–6999 | Assigned | IP HORIZON LLC | 515J | WESTWOOD | NJ |
| 2020-04-29 | 551-297-2XXX | 2000–2999 | Assigned | IP HORIZON LLC | 515J | BAYONNE | NJ |
| 2020-04-29 | 551-336-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | HACKENSACK | NJ |
| 2020-04-28 | 551-266-7XXX | 7000–7999 | Assigned | IP HORIZON LLC | 515J | FAIR LAWN | NJ |
| 2020-04-28 | 551-266-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | FAIR LAWN | NJ |
| 2020-04-28 | 551-304-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | RUTHERFORD | NJ |
| 2020-04-28 | 551-304-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | RUTHERFORD | NJ |
| 2020-04-28 | 551-336-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | HACKENSACK | NJ |
| 2020-04-28 | 551-356-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | KEARNY | NJ |
| 2020-04-28 | 551-356-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | KEARNY | NJ |
| 2020-04-28 | 551-465-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | LEONIA | NJ |
| 2020-04-28 | 551-465-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | LEONIA | NJ |
| 2020-04-28 | 551-529-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | UNION CITY | NJ |
| 2020-04-28 | 551-529-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | UNION CITY | NJ |
| 2020-04-28 | 551-557-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | PARK RIDGE | NJ |
| 2020-04-28 | 551-758-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2020-04-28 | 551-758-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2019-04-17 | 551-298-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2019-04-17 | 551-298-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2019-04-17 | 551-302-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | HACKENSACK | NJ |
| 2017-06-15 | 551-250-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | FAIR LAWN | NJ |
| 2017-06-15 | 551-272-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | LEONIA | NJ |
| 2017-06-15 | 551-274-6XXX | 6000–6999 | Assigned | IP HORIZON LLC | 515J | KEARNY | NJ |
| 2016-03-07 | 551-202-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | CLIFFSIDE | NJ |
| 2016-03-07 | 551-240-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | UNION CITY | NJ |
| 2016-03-07 | 551-241-5XXX | 5000–5999 | Assigned | IP HORIZON LLC | 515J | BAYONNE | NJ |
| 2016-03-07 | 551-255-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | HACKENSACK | NJ |
| 2016-03-07 | 551-255-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | HACKENSACK | NJ |
| 2016-03-07 | 551-256-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2016-03-07 | 551-263-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2016-03-07 | 551-900-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | DUMONT | NJ |
| 2015-10-14 | 551-248-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | CLOSTER | NJ |
| 2015-10-14 | 551-263-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | JERSEYCITY | NJ |
| 2015-10-14 | 551-264-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | RAMSEY | NJ |
| 2015-02-23 | 551-232-5XXX | 5000–5999 | Assigned | IP HORIZON LLC | 515J | BAYONNE | NJ |
| 2015-02-23 | 551-800-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | WESTWOOD | NJ |
| 2015-02-23 | 551-900-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | DUMONT | NJ |
| 2015-02-20 | 551-236-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | CLOSTER | NJ |
| 2015-02-20 | 551-252-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | RAMSEY | NJ |
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.