NumberResearchRecent thousands-block assignments
0 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/25/2026
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 667
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
Mar 2026
Feb 2026
Jan 2026
Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2021-07-29 | 667-343-0XXX | 0000–0999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-1XXX | 1000–1999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-2XXX | 2000–2999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-5XXX | 5000–5999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-6XXX | 6000–6999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-7XXX | 7000–7999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-8XXX | 8000–8999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-07-29 | 667-343-9XXX | 9000–9999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CAMBRIDGE | MD |
| 2021-04-07 | 667-257-6XXX | 6000–6999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | COLUMBIA | MD |
| 2021-01-26 | 667-296-6XXX | 6000–6999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2021-01-26 | 667-296-7XXX | 7000–7999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2021-01-26 | 667-296-8XXX | 8000–8999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2020-09-23 | 667-296-2XXX | 2000–2999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2020-09-23 | 667-296-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2020-09-23 | 667-296-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2020-09-10 | 667-254-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | CHESTERTN | MD |
| 2020-02-14 | 667-221-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | SALISBURY | MD |
| 2020-01-28 | 667-276-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BEL AIR | MD |
| 2019-02-21 | 667-264-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | DELMAR | MD |
| 2019-02-11 | 667-727-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | SUDLERSVL | MD |
| 2018-12-27 | 667-259-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2018-12-27 | 667-259-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2018-12-27 | 667-259-5XXX | 5000–5999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | REISTERSTN | MD |
| 2018-11-05 | 667-312-5XXX | 5000–5999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2017-01-30 | 667-312-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2016-03-02 | 667-786-7XXX | 7000–7999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | COLUMBIA | MD |
| 2015-12-17 | 667-313-0XXX | 0000–0999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-1XXX | 1000–1999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-2XXX | 2000–2999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-5XXX | 5000–5999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-6XXX | 6000–6999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-7XXX | 7000–7999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-8XXX | 8000–8999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-12-17 | 667-313-9XXX | 9000–9999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | PIKESVILLE | MD |
| 2015-11-04 | 667-312-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2015-08-05 | 667-228-5XXX | 5000–5999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | ABERDEEN | MD |
| 2015-07-31 | 667-218-7XXX | 7000–7999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2015-01-05 | 667-205-2XXX | 2000–2999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2014-07-18 | 667-214-2XXX | 2000–2999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2014-02-25 | 667-214-1XXX | 1000–1999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
| 2013-11-22 | 667-205-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 7228 | BALTIMORE | MD |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/25/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.