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 |
|---|---|---|---|---|---|---|---|
| 2014-03-25 | 423-398-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | KINGSPORT | TN |
| 2014-03-25 | 423-422-8XXX | 8000–8999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | MOSHEIM | TN |
| 2014-03-25 | 423-481-7XXX | 7000–7999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | ROAN MT | TN |
| 2014-03-25 | 423-512-7XXX | 7000–7999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | STONEY CRK | TN |
| 2014-03-25 | 423-516-7XXX | 7000–7999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | SULIVNGDNS | TN |
| 2014-03-25 | 423-528-7XXX | 7000–7999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | BAILEYTON | TN |
| 2014-03-25 | 423-797-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | BRISTOL | TN |
| 2014-03-21 | 423-362-7XXX | 7000–7999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2014-03-21 | 423-362-8XXX | 8000–8999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2014-03-21 | 423-425-9XXX | 9000–9999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | CHATTNOOGA | TN |
| 2014-03-14 | 423-353-7XXX | 7000–7999 | Assigned | POWERTEL NASHVILLE LICENSES, INC. | 7476 | MORRISTOWN | TN |
| 2014-03-14 | 423-353-8XXX | 8000–8999 | Assigned | POWERTEL NASHVILLE LICENSES, INC. | 7476 | MORRISTOWN | TN |
| 2014-03-10 | 423-430-4XXX | 4000–4999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | JOHNSON CY | TN |
| 2014-03-10 | 423-430-5XXX | 5000–5999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | JOHNSON CY | TN |
| 2014-03-10 | 423-480-7XXX | 7000–7999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | KINGSPORT | TN |
| 2014-03-10 | 423-480-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | KINGSPORT | TN |
| 2014-03-10 | 423-602-6XXX | 6000–6999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2014-03-10 | 423-823-7XXX | 7000–7999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | GREENEVL | TN |
| 2014-03-05 | 423-760-6XXX | 6000–6999 | Assigned | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| 2014-03-03 | 423-551-7XXX | 7000–7999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | CHATTNOOGA | TN |
| 2014-03-03 | 423-635-7XXX | 7000–7999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | CHATTNOOGA | TN |
| 2014-03-03 | 423-900-8XXX | 8000–8999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | JOHNSON CY | TN |
| 2014-02-20 | 423-588-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | GREENEVL | TN |
| 2014-02-20 | 423-805-6XXX | 6000–6999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2014-02-20 | 423-805-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2014-02-18 | 423-607-9XXX | 9000–9999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | LIMESTONE | TN |
| 2014-02-13 | 423-458-6XXX | 6000–6999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | CLEVELAND | TN |
| 2014-02-07 | 423-480-6XXX | 6000–6999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | KINGSPORT | TN |
| 2014-02-06 | 423-701-0XXX | 0000–0999 | Assigned | UNITED STATES CELLULAR - TN | 6278 | ROBBINS | TN |
| 2014-01-30 | 423-390-1XXX | 1000–1999 | Assigned | CHARTER IP ENABLED SERVICES, LLC | 792K | KINGSPORT | TN |
| 2014-01-15 | 423-405-6XXX | 6000–6999 | Assigned | TELEPORT COMMUNICATIONS AMERICA, LLC - TN | 114F | ATHENS | TN |
| 2014-01-07 | 423-356-1XXX | 1000–1999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2014-01-07 | 423-356-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2014-01-07 | 423-356-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2014-01-07 | 423-430-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | JOHNSON CY | TN |
| 2014-01-07 | 423-458-5XXX | 5000–5999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CLEVELAND | TN |
| 2013-12-27 | 423-207-9XXX | 9000–9999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | MIDWAY | TN |
| 2013-12-26 | 423-805-4XXX | 4000–4999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2013-12-26 | 423-805-7XXX | 7000–7999 | Assigned | ELECTRIC POWER BOARD OF CHATTANOOGA | 4645 | CHATTNOOGA | TN |
| 2013-12-19 | 423-823-9XXX | 9000–9999 | Assigned | COMCAST IP PHONE, LLC | 318J | GREENEVL | TN |
| 2013-12-18 | 423-603-7XXX | 7000–7999 | Assigned | AT&T ENTERPRISES, LLC | 516C | FORK RIDGE | TN |
| 2013-12-12 | 423-353-5XXX | 5000–5999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | MORRISTOWN | TN |
| 2013-12-12 | 423-588-6XXX | 6000–6999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | GREENEVL | TN |
| 2013-12-09 | 423-430-2XXX | 2000–2999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | JOHNSON CY | TN |
| 2013-12-09 | 423-602-4XXX | 4000–4999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | CHATTNOOGA | TN |
| 2013-11-07 | 423-268-7XXX | 7000–7999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | JOHNSON CY | TN |
| 2013-11-07 | 423-353-3XXX | 3000–3999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | MORRISTOWN | TN |
| 2013-11-07 | 423-480-5XXX | 5000–5999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | KINGSPORT | TN |
| 2013-11-07 | 423-805-5XXX | 5000–5999 | Assigned | COMCAST IP PHONE, LLC | 318J | CHATTNOOGA | TN |
| 2013-10-09 | 423-617-9XXX | 9000–9999 | Assigned | POWERTEL NASHVILLE LICENSES, INC. | 7476 | ATHENS | 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.