CASPER prefixes in area code 307
NANPA records 40 assigned NXX blocks to rate center CASPER in area code 307, 8.0% of the 499 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 13 holders hold those blocks, the largest being QWEST CORPORATION (14), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY (6), LEVEL 3 COMMUNICATIONS, LLC - WY (3). The earliest assignment on record here is 2001-07-26 and the most recent 2025-05-06. 21 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots.
Prefixes assigned here
| Prefix | Holder of record | Assigned | Pooled | In service |
|---|---|---|---|---|
| 307-215 | Bandwidth BANDWIDTH.COM CLEC, LLC - WY | 2001-07-26 | yes | yes |
| 307-224 | Lumen LEVEL 3 COMMUNICATIONS, LLC - WY | – | yes | yes |
| 307-232 | Lumen QWEST CORPORATION | – | no | yes |
| 307-233 | Lumen QWEST CORPORATION | – | no | yes |
| 307-234 | Lumen QWEST CORPORATION | – | no | yes |
| 307-235 | Lumen QWEST CORPORATION | – | no | yes |
| 307-237 | Lumen QWEST CORPORATION | – | no | yes |
| 307-243 | Onvoy ONVOY, LLC - WY | – | yes | yes |
| 307-247 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | yes | yes |
| 307-251 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | 2006-04-13 | no | yes |
| 307-253 | Lumen QWEST CORPORATION | 2008-03-10 | yes | yes |
| 307-258 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | – | no | yes |
| 307-259 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | – | no | yes |
| 307-261 | Lumen QWEST CORPORATION | – | no | yes |
| 307-262 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | – | no | yes |
| 307-265 | Lumen QWEST CORPORATION | – | no | yes |
| 307-266 | Lumen QWEST CORPORATION | – | no | yes |
| 307-267 | AT&T NEW CINGULAR WIRELESS PCS, LLC | – | yes | yes |
| 307-268 | Lumen QWEST CORPORATION | – | no | yes |
| 307-277 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | 2003-08-21 | no | yes |
| 307-301 | IP HORIZON LLC | 2023-10-09 | yes | yes |
| 307-315 | Charter CHARTER IP ENABLED SERVICES, LLC | 2007-05-11 | yes | yes |
| 307-333 | NUSO, LLC | – | yes | yes |
| 307-337 | Charter CHARTER IP ENABLED SERVICES, LLC | 2011-01-07 | yes | yes |
| 307-377 | UNION TELEPHONE COMPANY | – | no | yes |
| 307-394 | T-Mobile T-MOBILE USA, INC. | 2021-05-21 | yes | yes |
| 307-439 | Lumen LEVEL 3 COMMUNICATIONS, LLC - WY | – | yes | yes |
| 307-441 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | – | yes | yes |
| 307-452 | Onvoy ONVOY, LLC - WY | 2024-05-30 | yes | yes |
| 307-458 | Dish BOOST SUBSCRIBERCO L.L.C. | 2021-12-10 | yes | yes |
| 307-462 | Lumen LEVEL 3 COMMUNICATIONS, LLC - WY | 2002-06-11 | yes | yes |
| 307-472 | Lumen QWEST CORPORATION | – | no | yes |
| 307-473 | Lumen QWEST CORPORATION | – | yes | yes |
| 307-485 | T-Mobile T-MOBILE USA, INC. | 2025-05-06 | yes | yes |
| 307-577 | Lumen QWEST CORPORATION | – | no | yes |
| 307-702 | UNION TELEPHONE COMPANY | 2002-12-27 | no | yes |
| 307-724 | UNION TELEPHONE COMPANY | 2003-06-16 | no | yes |
| 307-776 | Vonage VONAGE AMERICA LLC | 2018-03-09 | yes | yes |
| 307-797 | AT&T NEW CINGULAR WIRELESS PCS, LLC | 2001-10-03 | yes | yes |
| 307-995 | Lumen QWEST CORPORATION | – | yes | yes |
The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.
Who holds the blocks
| Holder | Brand | Blocks | Share here |
|---|---|---|---|
| QWEST CORPORATION | Lumen | 14 | 35% |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | Verizon | 6 | 15% |
| LEVEL 3 COMMUNICATIONS, LLC - WY | Lumen | 3 | 7.5% |
| NEW CINGULAR WIRELESS PCS, LLC | AT&T | 3 | 7.5% |
| UNION TELEPHONE COMPANY | – | 3 | 7.5% |
| ONVOY, LLC - WY | Onvoy | 2 | 5% |
| CHARTER IP ENABLED SERVICES, LLC | Charter | 2 | 5% |
| T-MOBILE USA, INC. | T-Mobile | 2 | 5% |
| BANDWIDTH.COM CLEC, LLC - WY | Bandwidth | 1 | 2.5% |
| IP HORIZON LLC | – | 1 | 2.5% |
| NUSO, LLC | – | 1 | 2.5% |
| BOOST SUBSCRIBERCO L.L.C. | Dish | 1 | 2.5% |
| VONAGE AMERICA LLC | Vonage | 1 | 2.5% |
Frequently asked
Which prefixes belong to CASPER in area code 307?
40 blocks: 215, 224, 232, 233, 234, 235, 237, 243, 247, 251, 253, 258 and 28 more, all listed in the table above.
Which carriers have numbers in CASPER?
QWEST CORPORATION (14 blocks), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY (6 blocks), LEVEL 3 COMMUNICATIONS, LLC - WY (3 blocks), NEW CINGULAR WIRELESS PCS, LLC (3 blocks), UNION TELEPHONE COMPANY (3 blocks), ONVOY, LLC - WY (2 blocks). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.
Is CASPER a city?
It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.