NumberResearchRecent prefix assignments
374 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 10/01/2026
The Code holder is who opened each NPA-NXX prefix — not necessarily who holds the numbers. A prefix is 10,000 numbers, but under pooling its ten 1,000-number blocks are handed out individually, often to different carriers; the code holder may hold only one block, or none. The Thousands-blocks column shows how the ten blocks are really split — click which blocks → to see who holds each 1,000-number block and its last-4-digit range. Assignments are initial assignments; the current serving carrier may differ due to portability.
Most active assignees, last 30 days
New assignments by month
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Quick find in this area code:
| Assigned | NPA-NXX | Thousands-blocks taken (last-4 opening) | Code holder | OCN | Rate center | State |
|---|---|---|---|---|---|---|
| — | 423-467 | 5XXX which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | MIDWAY | TN |
| — | 423-468 | 0–9 XXXall 10 · 4 holders which blocks → | ONVOY, LLC - TN | 525E | CHATTNOOGA | TN |
| — | 423-469 | not yet reported which blocks → | SPOK, INC. | 6630 | NEWPORT | TN |
| — | 423-472 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CLEVELAND | TN |
| — | 423-473 | 3XXX which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CLEVELAND | TN |
| — | 423-474 | not yet reported which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | STONEY CRK | TN |
| — | 423-476 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CLEVELAND | TN |
| — | 423-477 | not yet reported which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | MIDWAY | TN |
| — | 423-478 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CLEVELAND | TN |
| — | 423-479 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CLEVELAND | TN |
| — | 423-485 | 3XXX which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-487 | 1XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | NEWPORT | TN |
| — | 423-488 | not yet reported which blocks → | NEW CINGULAR WIRELESS PCS, LLC - GA | 6214 | CHATTNOOGA | TN |
| — | 423-490 | 5XXX7XXX9XXX · 2 holders which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-493 | 3XXX which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-495 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-496 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | COPPERBSIN | TN |
| — | 423-499 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-500 | 0–9 XXXall 10 · 6 holders which blocks → | ONVOY, LLC - TN | 525E | ROGERSVL | TN |
| — | 423-502 | not yet reported which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | MIDWAY SUL | TN |
| — | 423-503 | none assigned yet which blocks → | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| — | 423-504 | none assigned yet which blocks → | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| — | 423-505 | none assigned yet which blocks → | POWERTEL ATLANTA LICENSES, INC. | 7473 | CHATTNOOGA | TN |
| — | 423-506 | 9XXX which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | ATHENS | TN |
| — | 423-507 | none assigned yet which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | ATHENS | TN |
| — | 423-508 | 2XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → | TELEPORT COMMUNICATIONS AMERICA, LLC - TN | 114F | CHATTNOOGA | TN |
| — | 423-510 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-511 | not yet reported which blocks → | MULTIPLE OCN LISTING | MULT | XXXXXXXXXX | TN |
| — | 423-514 | not yet reported which blocks → | SPOK, INC. | 6630 | CHATTNOOGA | TN |
| — | 423-517 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-519 | none assigned yet which blocks → | UNITED STATES CELLULAR - TN | 6278 | TELLICO PL | TN |
| — | 423-520 | 0XXX2XXX4XXX6XXX7XXX8XXX · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | MADISONVL | TN |
| — | 423-526 | none assigned yet which blocks → | BRIGHTSPEED OF EASTERN TENNESSEE, LLC | 0557 | NEWTAZWELL | TN |
| — | 423-528 | 0–9 XXXall 10 · 6 holders which blocks → | BANDWIDTH.COM CLEC, LLC - TN | 124F | BAILEYTON | TN |
| — | 423-532 | 0XXX4XXX7XXX8XXX9XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | NEWPORT | TN |
| — | 423-533 | not yet reported which blocks → | BLEDSOE TEL. COOP. | 0554 | NINE MILE | TN |
| — | 423-534 | not yet reported which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | BRISTOL | TN |
| — | 423-536 | 6XXX7XXX8XXX9XXX · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | SWEETWATER | TN |
| — | 423-537 | 4XXX6XXX8XXX which blocks → | PAETEC ITEL, LLC | 829J | BULLS GAP | TN |
| — | 423-538 | not yet reported which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | BLUFF CITY | TN |
| — | 423-539 | 0XXX1XXX2XXX4XXX5XXX6XXX7XXX9XXX · 2 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - GA | 6214 | ONEIDA | TN |
| — | 423-540 | 0–9 XXXall 10 · 4 holders which blocks → | ONVOY, LLC - TN | 525E | NEWPORT | TN |
| — | 423-542 | not yet reported which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | ELIZABTHTN | TN |
| — | 423-543 | not yet reported which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | ELIZABTHTN | TN |
| — | 423-547 | not yet reported which blocks → | UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN | 4510 | ELIZABTHTN | TN |
| — | 423-552 | 2XXX7XXX8XXX9XXX · 2 holders which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN | 6673 | GREENEVL | TN |
| — | 423-553 | not yet reported which blocks → | BELLSOUTH TELECOMM INC DBA SOUTH CENTRAL BELL TEL | 9419 | CHATTNOOGA | TN |
| — | 423-554 | not yet reported which blocks → | BLEDSOE TEL. COOP. | 0554 | COLLEGESTA | TN |
| — | 423-555 | not yet reported which blocks → | MULTIPLE OCN LISTING | MULT | DIR ASST | TN |
| — | 423-558 | 0–9 XXXall 10 · 3 holders which blocks → | ONVOY, LLC - TN | 525E | CHATTNOOGA | TN |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 10/01/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.