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 617
New assignments by month
Sep 2026
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| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2019-03-27 | 617-655-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | BOSTON | MA |
| 2019-03-27 | 617-655-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | BOSTON | MA |
| 2017-06-12 | 617-334-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | SO BOSTON | MA |
| 2017-06-12 | 617-829-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | QUINCY | MA |
| 2017-06-08 | 617-545-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | EVERETT | MA |
| 2017-06-08 | 617-716-7XXX | 7000–7999 | Assigned | IP HORIZON LLC | 515J | EASTBOSTON | MA |
| 2016-06-01 | 617-334-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | SO BOSTON | MA |
| 2016-06-01 | 617-612-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | WATERTOWN | MA |
| 2016-06-01 | 617-932-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | BELMONT | MA |
| 2016-05-27 | 617-370-9XXX | 9000–9999 | Assigned | IP HORIZON LLC | 515J | CHELSEA | MA |
| 2013-07-29 | 617-318-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | ROXBURY | MA |
| 2013-07-29 | 617-446-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | DORCHESTER | MA |
| 2013-07-29 | 617-454-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | NEWTON | MA |
| 2013-07-29 | 617-764-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | SOMERVILLE | MA |
| 2013-03-18 | 617-483-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | QUINCY | MA |
| 2013-03-15 | 617-360-5XXX | 5000–5999 | Assigned | IP HORIZON LLC | 515J | HYDE PARK | MA |
| 2013-03-15 | 617-370-7XXX | 7000–7999 | Assigned | IP HORIZON LLC | 515J | CHELSEA | MA |
| 2013-03-15 | 617-398-8XXX | 8000–8999 | Assigned | IP HORIZON LLC | 515J | CHARLESTN | MA |
| 2013-03-15 | 617-545-2XXX | 2000–2999 | Assigned | IP HORIZON LLC | 515J | EVERETT | MA |
| 2013-02-19 | 617-982-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | BOSTON | MA |
| 2002-05-29 | 617-833-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | HYDE PARK | MA |
| 2002-05-29 | 617-843-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | EVERETT | MA |
| 2002-05-29 | 617-952-4XXX | 4000–4999 | Assigned | IP HORIZON LLC | 515J | CHARLESTN | MA |
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.