NumberResearchRecent thousands-block assignments
0 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/21/2026
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 857
New assignments by month
Sep 2026
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2018-01-29 | 857-757-4XXX | 4000–4999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | CAMBRIDGE | MA |
| 2018-01-29 | 857-757-5XXX | 5000–5999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | CAMBRIDGE | MA |
| 2018-01-29 | 857-757-6XXX | 6000–6999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | CAMBRIDGE | MA |
| 2018-01-29 | 857-757-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | CAMBRIDGE | MA |
| 2017-10-18 | 857-306-9XXX | 9000–9999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2017-10-18 | 857-315-4XXX | 4000–4999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-07-21 | 857-762-0XXX | 0000–0999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-07-21 | 857-762-5XXX | 5000–5999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-07-21 | 857-762-6XXX | 6000–6999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-07-21 | 857-762-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-07-21 | 857-762-8XXX | 8000–8999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-07-05 | 857-406-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
| 2016-05-12 | 857-414-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BRIGHTON | MA |
| 2014-05-16 | 857-273-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | JAMAICA PL | MA |
| 2014-05-16 | 857-345-4XXX | 4000–4999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | HYDE PARK | MA |
| 2014-03-25 | 857-201-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | WINTHROP | MA |
| 2014-03-25 | 857-256-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | EASTBOSTON | MA |
| 2014-03-25 | 857-267-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | MILTON | MA |
| 2014-03-25 | 857-271-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | DORCHESTER | MA |
| 2014-03-25 | 857-304-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | WATERTOWN | MA |
| 2014-03-25 | 857-401-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | SO BOSTON | MA |
| 2013-08-28 | 857-323-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | CHELSEA | MA |
| 2013-03-08 | 857-317-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BOSTON | MA |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/21/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.