NumberResearchRecent thousands-block assignments
13 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, last 30 days — NPA 423
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 |
|---|---|---|---|---|---|---|---|
| 2011-10-13 | 423-800-0XXX | 0000–0999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2011-09-28 | 423-391-8XXX | 8000–8999 | Assigned | CHARTER IP ENABLED SERVICES, LLC | 792K | BLUFF CITY | TN |
| 2011-09-28 | 423-531-0XXX | 0000–0999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2011-09-28 | 423-531-6XXX | 6000–6999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2011-09-13 | 423-414-4XXX | 4000–4999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | CHATTNOOGA | TN |
| 2011-09-02 | 423-481-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | ROAN MT | TN |
| 2011-08-19 | 423-271-2XXX | 2000–2999 | Assigned | PAETEC ITEL, LLC | 829J | SWEETWATER | TN |
| 2011-08-19 | 423-405-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | ATHENS | TN |
| 2011-08-19 | 423-710-8XXX | 8000–8999 | Assigned | COMCAST IP PHONE, LLC | 318J | CHATTNOOGA | TN |
| 2011-08-17 | 423-228-9XXX | 9000–9999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SO PITTSBG | TN |
| 2011-08-17 | 423-454-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | DECATUR | TN |
| 2011-08-17 | 423-799-5XXX | 5000–5999 | Assigned | AT&T ENTERPRISES, LLC | 516C | SPRINGCITY | TN |
| 2011-08-17 | 423-815-4XXX | 4000–4999 | Assigned | AT&T ENTERPRISES, LLC | 516C | WHITWELL | TN |
| 2011-08-12 | 423-398-5XXX | 5000–5999 | Assigned | CHARTER IP ENABLED SERVICES, LLC | 792K | KINGSPORT | TN |
| 2011-08-08 | 423-437-8XXX | 8000–8999 | Assigned | COMCAST IP PHONE, LLC | 318J | LAFOLLETTE | TN |
| 2011-08-08 | 423-599-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CLEVELAND | TN |
| 2011-08-08 | 423-714-9XXX | 9000–9999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | MORRISTOWN | TN |
| 2011-08-08 | 423-913-4XXX | 4000–4999 | Assigned | COMCAST IP PHONE, LLC | 318J | JONESBORO | TN |
| 2011-07-27 | 423-464-7XXX | 7000–7999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | CLEVELAND | TN |
| 2011-07-22 | 423-264-0XXX | 0000–0999 | Assigned | COMCAST IP PHONE, LLC | 318J | VONORE | TN |
| 2011-07-22 | 423-398-3XXX | 3000–3999 | Assigned | ONVOY, LLC - TN | 525E | KINGSPORT | TN |
| 2011-07-22 | 423-588-4XXX | 4000–4999 | Assigned | ONVOY, LLC - TN | 525E | GREENEVL | TN |
| 2011-07-22 | 423-707-7XXX | 7000–7999 | Assigned | ONVOY, LLC - TN | 525E | ELIZABTHTN | TN |
| 2011-07-21 | 423-973-3XXX | 3000–3999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | SNEEDVILLE | TN |
| 2011-07-07 | 423-414-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2011-07-06 | 423-771-1XXX | 1000–1999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2011-07-06 | 423-771-2XXX | 2000–2999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2011-07-06 | 423-771-3XXX | 3000–3999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2011-07-06 | 423-771-5XXX | 5000–5999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2011-07-06 | 423-771-6XXX | 6000–6999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2011-07-06 | 423-771-8XXX | 8000–8999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2011-07-05 | 423-241-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - TN | 7278 | COPPERBSIN | TN |
| 2011-07-05 | 423-436-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - TN | 7278 | MADISONVL | TN |
| 2011-07-05 | 423-781-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - TN | 7278 | ETOWAH | TN |
| 2011-07-01 | 423-347-4XXX | 4000–4999 | Assigned | POWERTEL NASHVILLE LICENSES, INC. | 7476 | ROGERSVL | TN |
| 2011-07-01 | 423-492-1XXX | 1000–1999 | Assigned | POWERTEL NASHVILLE LICENSES, INC. | 7476 | MORRISTOWN | TN |
| 2011-07-01 | 423-492-2XXX | 2000–2999 | Assigned | POWERTEL NASHVILLE LICENSES, INC. | 7476 | MORRISTOWN | TN |
| 2011-06-28 | 423-460-1XXX | 1000–1999 | Assigned | CHARTER IP ENABLED SERVICES, LLC | 792K | MOUNTAINCY | TN |
| 2011-06-21 | 423-521-7XXX | 7000–7999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2011-06-21 | 423-521-8XXX | 8000–8999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2011-06-21 | 423-771-0XXX | 0000–0999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2011-06-09 | 423-588-2XXX | 2000–2999 | Assigned | SUNCOM DBA T-MOBILE USA | 8645 | GREENEVL | TN |
| 2011-06-07 | 423-207-5XXX | 5000–5999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | MIDWAY | TN |
| 2011-06-07 | 423-212-6XXX | 6000–6999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | BLOUNTVL | TN |
| 2011-06-07 | 423-291-6XXX | 6000–6999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | MOUNTAINCY | TN |
| 2011-06-07 | 423-352-7XXX | 7000–7999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | LAFOLLETTE | TN |
| 2011-06-07 | 423-398-1XXX | 1000–1999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | KINGSPORT | TN |
| 2011-06-07 | 423-415-4XXX | 4000–4999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | NEWPORT | TN |
| 2011-06-07 | 423-444-8XXX | 8000–8999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | LIMESTONE | TN |
| 2011-06-07 | 423-492-0XXX | 0000–0999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | MORRISTOWN | TN |
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.