Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records
Area code 307 prefixes
499 of the 786 possible NXX blocks are assigned in area code 307 (63.5% of capacity), spread across 92 rate centers and 52 holders. The largest holders are QWEST CORPORATION (83 blocks, 16.6%), UNION TELEPHONE COMPANY (65 blocks, 13.0%), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY (60 blocks, 12.0%). Grouped by brand, Lumen accounts for 124 blocks; brand-attributable holders cover 67% of the code, and the rest are CLECs, VoIP wholesalers and regional carriers that trade under their own names. The assignment records here run from 2001-01-29 to 2026-09-11, with 29 blocks handed out in 2002 alone. 279 blocks (56%) are in thousands-block pooling, meaning the block is shared between carriers in 1,000-number lots rather than held whole – which is why a single NXX can serve several carriers at once. 2 assigned blocks (493, 499) are not yet in service: assigned to a carrier but not open for calls, so a caller ID from one is spoofed. 69 were growth assignments – additional blocks to a carrier that had already filled its earlier ones.
499 assigned blocks of 786
92 rate centers
52 holders of record
56% in thousands-block pooling
Largest holders in 307
| Holder of record, as NANPA names it | Brand | Blocks | Share |
|---|---|---|---|
| QWEST CORPORATION | Lumen | 83 | 16.6% |
| UNION TELEPHONE COMPANY | – | 65 | 13% |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY | Verizon | 60 | 12% |
| NEW CINGULAR WIRELESS PCS, LLC | AT&T | 49 | 9.8% |
| ONVOY, LLC - WY | Onvoy | 40 | 8% |
| LEVEL 3 COMMUNICATIONS, LLC - WY | Lumen | 27 | 5.4% |
| BANDWIDTH.COM CLEC, LLC - WY | Bandwidth | 19 | 3.8% |
| RT COMMUNICATIONS | – | 17 | 3.4% |
| T-MOBILE USA, INC. | T-Mobile | 14 | 2.8% |
| UNION TEL. CO. | – | 11 | 2.2% |
| TRI-COUNTY TEL. ASSN., INC. | – | 9 | 1.8% |
| CHARTER IP ENABLED SERVICES, LLC | Charter | 8 | 1.6% |
Names are printed as they appear in the assignment records, which is the legal entity rather than the brand. Holding a block is not the same as serving the numbers in it: portability moves numbers between carriers and pooling splits a block between several.
Rate centers with their own page
Rate centers where at least three blocks are assigned, excluding the numbered metro zone codes. The remainder are in the full table below.
CHEYENNE 60CASPER 40JACKSON 21GILLETTE 21LARAMIE 18ROCK SPG 17SHERIDAN 17CODY 15RIVERTON 13EVANSTON 13LANDER 11POWELL 10GREENRIVER 10BUFFALO 9DOUGLAS 9RAWLINS 9AFTON 8WHEATLAND 8PINEDALE 7TORRINGTON 7LUSK 6KEMMERER 6NEWCASTLE 6SUNDANCE 5WORLAND 5LAKE 4COKEVILLE 4BORDER 4FREEDOM 4BIG PINEY 4GLENROCK 4WSPEARFISH 4HANNA 4LA GRANGE 4MT VIEW 4MORAN 4OLDFATHFUL 4THERMOPOLS 4LINGLE 3MAMMOTH 3DUBOIS 3FARSON 3JEFFREY CY 3WRIGHT 3SHOSHONI 3SARATOGA 3BAGGS 3MEDICINBOW 3LABARGE 3WBLLFOURCH 3LYMAN 3
All 499 assigned blocks
One row per NXX. “Pooled” means carriers draw 1,000-number lots from the block rather than holding all 10,000, so a pooled prefix can belong to several carriers at once. “Not in service” means assigned but not yet open for calls – a caller ID from one of those is necessarily spoofed. The holder column gives the brand where the legal entity maps to one; the full legal names are in the holders table above, exactly as NANPA records them.
| Prefix | Holder of record | Rate center | Assigned | Pooled | In service |
|---|---|---|---|---|---|
| 307-200 | Lumen | JACKSON | 2002-08-16 | yes | yes |
| 307-201 | Lumen | JACKSON | 2003-01-07 | yes | yes |
| 307-202 | AT&T | POWELL | 2003-01-21 | yes | yes |
| 307-203 | T-Mobile | JACKSON | 2001-03-14 | yes | yes |
| 307-204 | AIRUS, INC. - WY | CODY | 2018-02-06 | yes | yes |
| 307-205 | Lumen | LINGLE | 2016-11-16 | yes | yes |
| 307-206 | Verizon | LANDER | 2013-12-05 | yes | yes |
| 307-207 | AIRUS, INC. - WY | LAKE | 2018-12-06 | yes | yes |
| 307-209 | Verizon | ROCK SPG | 2014-12-19 | yes | yes |
| 307-210 | AT&T | SOUTHESRDN | 2020-04-03 | yes | yes |
| 307-212 | Lumen | ROCK SPG | 2002-07-16 | yes | yes |
| 307-213 | Lumen | CODY | 2002-07-16 | yes | yes |
| 307-214 | Verizon | CHEYENNE | 2003-01-06 | – | yes |
| 307-215 | Bandwidth | CASPER | 2001-07-26 | yes | yes |
| 307-216 | AT&T | LUSK | 2002-10-09 | yes | yes |
| 307-217 | AT&T | BUFFALO | 2002-10-09 | yes | yes |
| 307-218 | Onvoy | SHERIDAN | 2019-08-13 | yes | yes |
| 307-219 | Lumen | POWELL | 2015-03-26 | yes | yes |
| 307-220 | T-Mobile | CHEYENNE | – | yes | yes |
| 307-221 | T-Mobile | CHEYENNE | – | yes | yes |
| 307-222 | Lumen | CHEYENNE | – | yes | yes |
| 307-223 | Lumen | LARAMIE | – | yes | yes |
| 307-224 | Lumen | CASPER | – | yes | yes |
| 307-225 | Charter | LARAMIE | 2020-09-02 | yes | yes |
| 307-226 | Verizon | AFTON | 2015-12-28 | yes | yes |
| 307-227 | Onvoy | MAMMOTH | – | yes | yes |
| 307-228 | Bandwidth | GILLETTE | 2014-05-23 | yes | yes |
| 307-229 | AT&T | COKEVILLE | 2015-02-17 | yes | yes |
| 307-230 | Bandwidth | BORDER | 2022-07-19 | yes | yes |
| 307-231 | Verizon | PINEDALE | – | yes | yes |
| 307-232 | Lumen | CASPER | – | – | yes |
| 307-233 | Lumen | CASPER | – | – | yes |
| 307-234 | Lumen | CASPER | – | – | yes |
| 307-235 | Lumen | CASPER | – | – | yes |
| 307-236 | AT&T | BURNS | 2020-04-03 | yes | yes |
| 307-237 | Lumen | CASPER | – | – | yes |
| 307-238 | AT&T | HAMITNDOME | 2017-08-22 | yes | yes |
| 307-239 | AT&T | DUBOIS | 2015-11-05 | yes | yes |
| 307-240 | Verizon | RIVERTON | – | yes | yes |
| 307-241 | AT&T | WHEATLAND | – | yes | yes |
| 307-242 | Lumen | LAKE | – | yes | yes |
| 307-243 | Onvoy | CASPER | – | yes | yes |
| 307-244 | SILVER STAR TEL CO INC | FREEDOM | 2019-05-15 | yes | yes |
| 307-245 | RT COMMUNICATIONS | PINEBLUFFS | – | – | yes |
| 307-246 | RT COMMUNICATIONS | ALBIN | – | – | yes |
| 307-247 | AT&T | CASPER | – | yes | yes |
| 307-248 | Verizon | AFTON | 2003-03-25 | yes | yes |
| 307-249 | Telnyx | JACKSON | 2017-03-24 | yes | yes |
| 307-250 | Verizon | CODY | – | yes | yes |
| 307-251 | Verizon | CASPER | 2006-04-13 | – | yes |
| 307-252 | UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS | ROCK SPG | – | – | yes |
| 307-253 | Lumen | CASPER | 2008-03-10 | yes | yes |
| 307-254 | Verizon | POWELL | 2003-09-11 | yes | yes |
| 307-255 | UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS | EVANSTON | 2002-07-15 | – | yes |
| 307-256 | T-Mobile | CHEYENNE | 2004-01-05 | yes | yes |
| 307-257 | Lumen | GILLETTE | 2004-05-19 | yes | yes |
| 307-258 | Verizon | CASPER | – | – | yes |
| 307-259 | Verizon | CASPER | – | – | yes |
| 307-260 | UNION TELEPHONE COMPANY | BIG PINEY | – | – | yes |
| 307-261 | Lumen | CASPER | – | – | yes |
| 307-262 | Verizon | CASPER | – | – | yes |
| 307-263 | CSC WIRELESS, LLC | CHEYENNE | 2019-10-16 | yes | yes |
| 307-264 | Charter | JACKSON | 2014-03-24 | yes | yes |
| 307-265 | Lumen | CASPER | – | – | yes |
| 307-266 | Lumen | CASPER | – | – | yes |
| 307-267 | AT&T | CASPER | – | yes | yes |
| 307-268 | Lumen | CASPER | – | – | yes |
| 307-269 | Lumen | WHEATLAND | – | yes | yes |
| 307-270 | UNION TELEPHONE COMPANY | COKEVILLE | – | – | yes |
| 307-271 | Lumen | POWELL | 2004-05-26 | yes | yes |
| 307-272 | Verizon | CODY | – | – | yes |
| 307-273 | Lumen | FARSON | – | yes | yes |
| 307-274 | Verizon | CHEYENNE | 2004-07-14 | yes | yes |
| 307-275 | Verizon | CHEYENNE | 2005-01-12 | yes | yes |
| 307-276 | Lumen | BIG PINEY | – | yes | yes |
| 307-277 | Verizon | CASPER | 2003-08-21 | – | yes |
| 307-278 | Lumen | BUFFALO | 2004-05-19 | yes | yes |
| 307-279 | ALL WEST COMMUNICATIONS - WY | COKEVILLE | – | – | yes |
| 307-280 | UNION TELEPHONE COMPANY | FARSON | – | – | yes |
| 307-281 | Verizon | SUNDANCE | – | yes | yes |
| 307-282 | Verizon | SUNDANCE | – | yes | yes |
| 307-283 | RANGE TEL COOP INC | SUNDANCE | – | – | yes |
| 307-284 | SILVER STAR TELEPHONE COMPANY, INC. - WY | JACKSON | 2019-11-20 | yes | yes |
| 307-285 | AIRUS, INC. - WY | BUFFALO | 2020-05-21 | yes | yes |
| 307-286 | Verizon | CHEYENNE | 2004-01-19 | – | yes |
| 307-287 | Verizon | CHEYENNE | 2006-05-23 | – | yes |
| 307-288 | Lumen | EVANSTON | 2004-05-19 | yes | yes |
| 307-289 | Comcast | CHEYENNE | 2023-04-14 | yes | yes |
| 307-290 | AT&T | SUNDANCE | – | yes | yes |
| 307-291 | COMMIO, LLC | CODY | 2021-10-28 | yes | yes |
| 307-292 | HD CARRIER LLC | CHEYENNE | 2020-06-17 | yes | yes |
| 307-293 | Onvoy | GUERNSEY | 2021-03-02 | yes | yes |
| 307-294 | AT&T | BIG PINEY | 2023-08-01 | yes | yes |
| 307-295 | Onvoy | TORRINGTON | 2023-09-13 | yes | yes |
| 307-296 | Onvoy | CODY | – | yes | yes |
| 307-297 | UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS | GREENRIVER | – | – | yes |
| 307-298 | Lumen | DOUGLAS | 2004-05-19 | yes | yes |
| 307-299 | AT&T | GILLETTE | 2003-10-21 | – | yes |
| 307-300 | Onvoy | POWELL | 2019-10-10 | yes | yes |
| 307-301 | IP HORIZON LLC | CASPER | 2023-10-09 | yes | yes |
| 307-302 | Bandwidth | CODY | 2020-08-17 | yes | yes |
| 307-303 | Bandwidth | GREENRIVER | 2020-11-09 | yes | yes |
| 307-304 | AT&T | JEFFREY CY | 2020-09-17 | yes | yes |
| 307-305 | AT&T | MIDWEST | 2021-03-05 | yes | yes |
| 307-306 | STRATUS NETWORKS | DOUGLAS | 2020-12-21 | yes | yes |
| 307-309 | AT&T | GLENROCK | 2006-09-08 | yes | yes |
| 307-310 | Charter | CHEYENNE | 2019-10-23 | yes | yes |
| 307-312 | Bandwidth | WSPEARFISH | 2012-06-19 | yes | yes |
| 307-313 | Lumen | EVANSTON | – | yes | yes |
| 307-314 | Bandwidth | LARAMIE | – | yes | yes |
| 307-315 | Charter | CASPER | 2007-05-11 | yes | yes |
| 307-316 | Onvoy | CHEYENNE | 2006-03-20 | yes | yes |
| 307-317 | Onvoy | CHEYENNE | 2017-05-22 | yes | yes |
| 307-318 | Bandwidth | WRIGHT | 2021-01-15 | yes | yes |
| 307-319 | AT&T | SHOSHONI | 2020-09-17 | yes | yes |
| 307-320 | UNION TELEPHONE COMPANY | RAWLINS | – | – | yes |
| 307-321 | Verizon | RAWLINS | – | – | yes |
| 307-322 | Lumen | WHEATLAND | – | – | yes |
| 307-323 | Lumen | PINEDALE | 2019-07-22 | yes | yes |
| 307-324 | Lumen | RAWLINS | – | – | yes |
| 307-325 | UNION TEL. CO. | HANNA | – | – | yes |
| 307-326 | UNION TEL. CO. | SARATOGA | – | – | yes |
| 307-327 | UNION TEL. CO. | ENCAMPMENT | – | – | yes |
| 307-328 | Lumen | RAWLINS | – | yes | yes |
| 307-329 | UNION TELEPHONE COMPANY | SARATOGA | – | – | yes |
| 307-330 | UNION TELEPHONE COMPANY | LANDER | – | – | yes |
| 307-331 | Verizon | WHEATLAND | – | yes | yes |
| 307-332 | Lumen | LANDER | – | – | yes |
| 307-333 | NUSO, LLC | CASPER | – | yes | yes |
| 307-334 | Lumen | LUSK | – | yes | yes |
| 307-335 | Lumen | LANDER | – | yes | yes |
| 307-336 | Lumen | DANIEL | 2019-07-22 | yes | yes |
| 307-337 | Charter | CASPER | 2011-01-07 | yes | yes |
| 307-338 | Verizon | TORRINGTON | 2011-01-12 | yes | yes |
| 307-339 | UNION TELEPHONE COMPANY | HANNA | – | – | yes |
| 307-340 | Verizon | LUSK | – | yes | yes |
| 307-341 | PROJECT TEL. CO., INC. | SOUTHWYOLA | – | – | yes |
| 307-342 | Onvoy | JACKSON | – | yes | yes |
| 307-343 | Verizon | LARAMIE | 2009-07-16 | yes | yes |
| 307-344 | Lumen | MAMMOTH | – | yes | yes |
| 307-345 | UNION TELEPHONE COMPANY | LANDER | – | – | yes |
| 307-346 | Dish | CHEYENNE | 2021-07-14 | yes | yes |
| 307-347 | RT COMMUNICATIONS | WORLAND | – | – | yes |
| 307-348 | UNION TEL. CO. | HANNA | – | – | yes |
| 307-349 | Verizon | LANDER | – | – | yes |
| 307-350 | UNION TELEPHONE COMPANY | ROCK SPG | – | – | yes |
| 307-351 | AT&T | DOUGLAS | – | yes | yes |
| 307-352 | Lumen | ROCK SPG | – | yes | yes |
| 307-353 | COLUMBINE TELCO DBA SILVER STAR COMMUNICATIONS | ALTA | – | – | yes |
| 307-354 | UNION TELEPHONE COMPANY | ROCK SPG | 2001-03-27 | – | yes |
| 307-355 | T-Mobile | LA GRANGE | 2020-07-29 | yes | yes |
| 307-356 | UNION TEL. CO. | SHIRLEBSIN | – | – | yes |
| 307-357 | Onvoy | LARAMIE | 2023-10-01 | yes | yes |
| 307-358 | Lumen | DOUGLAS | – | – | yes |
| 307-359 | Verizon | DOUGLAS | – | yes | yes |
| 307-360 | UNION TELEPHONE COMPANY | PINEDALE | – | – | yes |
| 307-361 | AT&T | BAGGS | 2021-03-05 | yes | yes |
| 307-362 | Lumen | ROCK SPG | – | – | yes |
| 307-363 | Bandwidth | GILLETTE | 2010-08-30 | yes | yes |
| 307-364 | Bandwidth | GREENRIVER | 2014-05-23 | yes | yes |
| 307-365 | AT&T | CHEYENNE | 2008-03-03 | yes | yes |
| 307-366 | TRI-COUNTY TEL. ASSN., INC. | TEN SLEEP | – | – | yes |
| 307-367 | Lumen | PINEDALE | – | yes | yes |
| 307-368 | Verizon | AFTON | 2021-02-10 | yes | yes |
| 307-369 | Charter | CHEYENNE | 2011-01-10 | yes | yes |
| 307-370 | Verizon | RAWLINS | – | yes | yes |
| 307-371 | Verizon | ROCK SPG | – | – | yes |
| 307-372 | Onvoy | DOUGLAS | 2020-08-10 | yes | yes |
| 307-373 | Charter | GREYBULL | – | yes | yes |
| 307-374 | Vonage | ROCK SPG | – | yes | yes |
| 307-375 | RT COMMUNICATIONS | WORLAND | – | – | yes |
| 307-376 | AT&T | ALPINE | 2021-08-11 | – | yes |
| 307-377 | UNION TELEPHONE COMPANY | CASPER | – | – | yes |
| 307-378 | UNION TEL. CO. | ROCK RIVER | – | – | yes |
| 307-379 | Lumen | MEDICINBOW | – | yes | yes |
| 307-380 | UNION TELEPHONE COMPANY | BAGGS | – | – | yes |
| 307-381 | Bandwidth | SHERIDAN | 2021-04-23 | yes | yes |
| 307-382 | Lumen | ROCK SPG | – | – | yes |
| 307-383 | DUBOIS TEL. EXCH., INC. | BAGGS | – | – | yes |
| 307-384 | COMMIO, LLC | AFTON | 2021-11-03 | yes | yes |
| 307-385 | T-Mobile | JACKSON | 2025-11-06 | yes | yes |
| 307-386 | UNION TEL. CO. | LABARGE | – | – | yes |
| 307-387 | Bandwidth | GILLETTE | 2021-10-01 | yes | yes |
| 307-388 | AT&T | WORLAND | – | yes | yes |
| 307-389 | Verizon | ROCK SPG | – | – | yes |
| 307-390 | UNION TELEPHONE COMPANY | LABARGE | – | – | yes |
| 307-391 | AT&T | MOORCROFT | 2005-03-14 | yes | yes |
| 307-392 | Lumen | BORDER | 2006-06-21 | yes | yes |
| 307-393 | AIRUS, INC. - WY | EVANSTON | 2021-03-31 | yes | yes |
| 307-394 | T-Mobile | CASPER | 2021-05-21 | yes | yes |
| 307-395 | Bandwidth | LARAMIE | 2021-08-11 | yes | yes |
| 307-396 | Bandwidth | GREENRIVER | 2021-10-20 | yes | yes |
| 307-397 | AT&T | HANNA | 2021-11-05 | yes | yes |
| 307-398 | AT&T | LABARGE | 2021-11-05 | yes | yes |
| 307-399 | Verizon | LARAMIE | 2002-05-16 | – | yes |
| 307-400 | TERRA NOVA TELECOM INC. | CHEYENNE | 2020-01-24 | yes | yes |
| 307-401 | AT&T | TORRINGTON | – | yes | yes |
| 307-402 | AT&T | MT VIEW | 2021-11-05 | yes | yes |
| 307-403 | Bandwidth | MORAN | 2022-02-22 | yes | yes |
| 307-404 | AT&T | MEDICINBOW | 2018-05-23 | yes | yes |
| 307-405 | Onvoy | WBLLFOURCH | 2023-05-24 | yes | yes |
| 307-407 | Onvoy | WSPEARFISH | 2020-08-10 | yes | yes |
| 307-408 | AT&T | LYMAN | 2021-11-05 | yes | yes |
| 307-409 | AT&T | LA GRANGE | 2018-02-20 | yes | yes |
| 307-410 | T-Mobile | POWELL | 2022-03-22 | yes | yes |
| 307-412 | AT&T | CHEYENNE | 2022-09-23 | yes | yes |
| 307-413 | AT&T | JACKSON | 2001-01-29 | – | yes |
| 307-414 | AIRUS, INC. - WY | CHEYENNE | 2015-08-24 | yes | yes |
| 307-415 | NUSO, LLC | CHEYENNE | 2023-03-03 | yes | yes |
| 307-416 | Lumen | PINEDALE | 2023-05-24 | yes | yes |
| 307-417 | Onvoy | RAWLINS | – | yes | yes |
| 307-418 | AT&T | JACKSON | 2023-06-09 | yes | yes |
| 307-419 | T-Mobile | CODY | 2022-03-24 | yes | yes |
| 307-420 | Onvoy | LINGLE | 2023-05-24 | yes | yes |
| 307-421 | Verizon | CHEYENNE | – | – | yes |
| 307-422 | CHUGWATER TEL. CO. | CHUGWATER | – | – | yes |
| 307-423 | Bandwidth | BUFFALO | 2021-11-05 | yes | yes |
| 307-424 | Onvoy | LAKE | 2023-05-24 | yes | yes |
| 307-425 | ADVANCED COMMUNICATIONS TECHNOLOGY, INC. - WY | BUFFALO | 2011-03-30 | – | yes |
| 307-426 | Charter | CHEYENNE | 2007-05-22 | yes | yes |
| 307-427 | Onvoy | MAMMOTH | 2023-05-24 | yes | yes |
| 307-428 | T-Mobile | DOUGLAS | 2023-12-01 | yes | yes |
| 307-429 | Bandwidth | SHERIDAN | 2013-05-23 | yes | yes |
| 307-430 | Onvoy | OLDFATHFUL | 2023-12-11 | yes | yes |
| 307-431 | Verizon | WORLAND | – | yes | yes |
| 307-432 | Lumen | CHEYENNE | – | yes | yes |
| 307-433 | Lumen | CHEYENNE | – | yes | yes |
| 307-434 | Onvoy | GILLETTE | 2024-02-05 | yes | yes |
| 307-435 | T-Mobile | SHERIDAN | 2025-12-03 | yes | yes |
| 307-436 | Lumen | GLENROCK | – | – | yes |
| 307-437 | RT COMMUNICATIONS | MIDWEST | – | – | yes |
| 307-438 | Verizon | LANDER | 2007-06-19 | yes | yes |
| 307-439 | Lumen | CASPER | – | yes | yes |
| 307-440 | Charter | BASIN | – | yes | yes |
| 307-441 | Verizon | CASPER | – | yes | yes |
| 307-442 | Onvoy | EVANSTON | 2024-02-29 | yes | yes |
| 307-443 | COMMIO, LLC | CHEYENNE | 2019-06-18 | yes | yes |
| 307-444 | ALL WEST/WYOMING, INC. | EVANSTON | – | – | yes |
| 307-445 | Onvoy | KEMMERER | 2021-02-05 | yes | yes |
| 307-446 | Onvoy | WSPEARFISH | 2023-05-24 | yes | yes |
| 307-447 | Lumen | SARATOGA | 2015-10-08 | yes | yes |
| 307-448 | Verizon | ROCK SPG | 2011-05-12 | yes | yes |
| 307-449 | AT&T | ROCK SPG | – | yes | yes |
| 307-450 | UNION TELEPHONE COMPANY | DUBOIS | – | – | yes |
| 307-451 | Vonage | ROCK SPG | 2024-05-06 | yes | yes |
| 307-452 | Onvoy | CASPER | 2024-05-30 | yes | yes |
| 307-453 | Onvoy | JACKSON | 2024-06-06 | yes | yes |
| 307-454 | Onvoy | RIVERTON | 2024-06-07 | yes | yes |
| 307-455 | DUBOIS TEL. EXCH., INC. | DUBOIS | – | – | yes |
| 307-456 | Lumen | BIG PINEY | 2019-07-22 | yes | yes |
| 307-457 | RT COMMUNICATIONS | GAS HILLS | – | – | yes |
| 307-458 | Dish | CASPER | 2021-12-10 | yes | yes |
| 307-459 | Lumen | CHEYENNE | 2002-06-11 | yes | yes |
| 307-460 | Lumen | LARAMIE | 2002-06-11 | yes | yes |
| 307-461 | Lumen | SHERIDAN | 2002-06-11 | yes | yes |
| 307-462 | Lumen | CASPER | 2002-06-11 | yes | yes |
| 307-463 | Lumen | RIVERTON | 2002-06-11 | yes | yes |
| 307-464 | Lumen | WRIGHT | – | yes | yes |
| 307-465 | RT COMMUNICATIONS | NEWCASTLE | – | – | yes |
| 307-466 | Verizon | GREENRIVER | – | yes | yes |
| 307-467 | RT COMMUNICATIONS | HULETT | – | – | yes |
| 307-468 | RT COMMUNICATIONS | UPTON | – | – | yes |
| 307-469 | TRI-COUNTY TEL. ASSN., INC. | HYATTVILLE | – | – | yes |
| 307-471 | AT&T | LUSK | 2024-09-10 | yes | yes |
| 307-472 | Lumen | CASPER | – | – | yes |
| 307-473 | Lumen | CASPER | – | yes | yes |
| 307-474 | Onvoy | CODY | 2024-12-12 | yes | yes |
| 307-475 | Telnyx | CHEYENNE | 2016-12-21 | yes | yes |
| 307-476 | Onvoy | LARAMIE | 2025-01-09 | yes | yes |
| 307-477 | UNION TELEPHONE COMPANY | CHEYENNE | – | – | yes |
| 307-478 | T-Mobile | LA GRANGE | 2025-02-05 | yes | yes |
| 307-479 | Onvoy | POWELL | 2025-02-12 | yes | yes |
| 307-480 | AT&T | THERMOPOLS | 2005-06-15 | yes | yes |
| 307-481 | Onvoy | LUSK | 2007-03-14 | yes | yes |
| 307-482 | T-Mobile | WHEATLAND | 2025-04-08 | yes | yes |
| 307-483 | AT&T | RAWLINS | 2025-04-30 | yes | yes |
| 307-484 | WAVENATION, LLC | CHEYENNE | 2026-01-07 | yes | yes |
| 307-485 | T-Mobile | CASPER | 2025-05-06 | yes | yes |
| 307-486 | DUBOIS TEL. EXCH., INC. | CROWHEART | – | – | yes |
| 307-487 | Verizon | GILLETTE | 2018-10-09 | yes | yes |
| 307-488 | Bandwidth | LANDER | 2018-04-19 | yes | yes |
| 307-489 | AT&T | SHIRLEBSIN | 2018-05-30 | yes | yes |
| 307-490 | Charter | UPTON | 2026-02-25 | yes | yes |
| 307-493 | UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS | URIE | 2026-09-11 | yes | no |
| 307-496 | EXIANT COMMUNICATIONS LLC | LAKE | 2026-03-31 | yes | yes |
| 307-497 | ALL WEST COMMUNICATIONS - WY | EVANSTON | – | – | yes |
| 307-499 | UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS | LYMAN | 2026-09-11 | yes | no |
| 307-500 | Onvoy | BORDER | 2021-02-05 | yes | yes |
| 307-507 | WIDE VOICE, LLC - WY | CHEYENNE | 2025-04-03 | yes | yes |
| 307-509 | Bandwidth | CHEYENNE | 2008-09-05 | yes | yes |
| 307-514 | Charter | CHEYENNE | – | yes | yes |
| 307-520 | UNION TELEPHONE COMPANY | MEDICINBOW | – | – | yes |
| 307-522 | AIRUS, INC. - WY | ROCK SPG | 2017-08-07 | yes | yes |
| 307-527 | Lumen | CODY | – | yes | yes |
| 307-529 | Onvoy | CHEYENNE | 2009-08-25 | yes | yes |
| 307-532 | Lumen | TORRINGTON | – | – | yes |
| 307-533 | Verizon | SHERIDAN | 2006-12-05 | yes | yes |
| 307-534 | Lumen | TORRINGTON | – | yes | yes |
| 307-537 | Lumen | PINEDALE | – | – | yes |
| 307-540 | UNION TELEPHONE COMPANY | JEFFREY CY | – | – | yes |
| 307-541 | UNION TELEPHONE COMPANY | MORAN | – | – | yes |
| 307-543 | Lumen | MORAN | – | yes | yes |
| 307-544 | RT COMMUNICATIONS | JEFFREY CY | – | – | yes |
| 307-545 | Lumen | OLDFATHFUL | – | yes | yes |
| 307-547 | RT COMMUNICATIONS | BURNS | – | – | yes |
| 307-548 | TRI-COUNTY TEL. ASSN., INC. | LOVELL | – | – | yes |
| 307-549 | UNION TELEPHONE COMPANY | OLDFATHFUL | – | – | yes |
| 307-554 | Onvoy | GLENROCK | – | yes | yes |
| 307-556 | Onvoy | RIVERTON | 2021-02-05 | yes | yes |
| 307-567 | UNION TELEPHONE COMPANY | GILLETTE | – | – | yes |
| 307-568 | TRI-COUNTY TEL. ASSN., INC. | BASIN | – | – | yes |
| 307-575 | Verizon | TORRINGTON | 2002-06-28 | yes | yes |
| 307-576 | COLUMBINE TELCO DBA SILVER STAR COMMUNICATIONS | LEIGHCNYON | – | – | yes |
| 307-577 | Lumen | CASPER | – | – | yes |
| 307-578 | Lumen | CODY | – | yes | yes |
| 307-586 | TRI TEL, INC. | CODY | 2005-04-01 | – | yes |
| 307-587 | Lumen | CODY | – | – | yes |
| 307-600 | UNION TELEPHONE COMPANY | COKEVILLE | – | – | yes |
| 307-620 | Verizon | BUFFALO | – | yes | yes |
| 307-621 | Verizon | BUFFALO | – | yes | yes |
| 307-622 | AT&T | GILLETTE | 2010-11-24 | yes | yes |
| 307-624 | AT&T | DOUGLAS | 2001-10-03 | yes | yes |
| 307-629 | AT&T | NEWCASTLE | 2004-12-21 | yes | yes |
| 307-630 | Verizon | CHEYENNE | – | – | yes |
| 307-631 | Verizon | CHEYENNE | – | – | yes |
| 307-632 | Lumen | CHEYENNE | – | – | yes |
| 307-633 | Lumen | CHEYENNE | – | yes | yes |
| 307-634 | Lumen | CHEYENNE | – | – | yes |
| 307-635 | Lumen | CHEYENNE | – | – | yes |
| 307-637 | Lumen | CHEYENNE | – | – | yes |
| 307-638 | Lumen | CHEYENNE | – | – | yes |
| 307-639 | EXIANT COMMUNICATIONS LLC | LANDER | 2026-03-31 | yes | yes |
| 307-640 | AT&T | CHEYENNE | – | yes | yes |
| 307-643 | Lumen | WSPEARFISH | – | – | yes |
| 307-645 | PROJECT TEL. CO., INC. | CLARK | – | – | yes |
| 307-649 | RT COMMUNICATIONS | CARPENTER | – | – | yes |
| 307-650 | AIRUS, INC. - WY | CHEYENNE | – | yes | yes |
| 307-654 | SILVER STAR TEL CO INC | ALPINE | – | – | yes |
| 307-655 | Lumen | SHERIDAN | – | yes | yes |
| 307-660 | AT&T | GILLETTE | – | – | yes |
| 307-663 | GOLDEN WEST TEL COOP INC DBA GOLDEN WEST TELECOMM | W EDGEMONT | – | – | yes |
| 307-664 | TRI-COUNTY TEL. ASSN., INC. | FRANNIE | – | – | yes |
| 307-666 | FRACTEL, LLC | CHEYENNE | 2019-05-23 | yes | yes |
| 307-667 | Onvoy | RAWLINS | 2021-02-28 | yes | yes |
| 307-670 | Verizon | GILLETTE | – | yes | yes |
| 307-672 | Lumen | SHERIDAN | – | – | yes |
| 307-673 | Lumen | SHERIDAN | – | – | yes |
| 307-674 | Lumen | SHERIDAN | – | – | yes |
| 307-675 | ADVANCED COMMUNICATIONS TECHNOLOGY, INC. - WY | SHERIDAN | 2003-01-30 | – | yes |
| 307-677 | Verizon | EVANSTON | – | yes | yes |
| 307-679 | Verizon | EVANSTON | – | – | yes |
| 307-680 | AT&T | GILLETTE | – | – | yes |
| 307-681 | ADVANCED COMMUNICATIONS TECHNOLOGY, INC. - WY | GILLETTE | 2010-04-16 | – | yes |
| 307-682 | Lumen | GILLETTE | – | – | yes |
| 307-683 | Lumen | SHERIDAN | – | yes | yes |
| 307-684 | Lumen | BUFFALO | – | – | yes |
| 307-685 | Lumen | GILLETTE | – | – | yes |
| 307-686 | Lumen | GILLETTE | – | – | yes |
| 307-687 | Lumen | GILLETTE | – | – | yes |
| 307-688 | Lumen | GILLETTE | 2004-05-24 | – | yes |
| 307-689 | Verizon | GILLETTE | – | – | yes |
| 307-690 | Verizon | JACKSON | – | – | yes |
| 307-696 | AT&T | GILLETTE | 2008-09-22 | yes | yes |
| 307-699 | Verizon | JACKSON | – | yes | yes |
| 307-701 | UNION TELEPHONE COMPANY | CHEYENNE | 2002-12-27 | – | yes |
| 307-702 | UNION TELEPHONE COMPANY | CASPER | 2002-12-27 | – | yes |
| 307-703 | UNION TELEPHONE COMPANY | LARAMIE | 2002-12-27 | – | yes |
| 307-704 | UNION TELEPHONE COMPANY | GILLETTE | 2002-12-27 | – | yes |
| 307-705 | UNION TELEPHONE COMPANY | ROCK SPG | 2003-06-16 | – | yes |
| 307-706 | UNION TELEPHONE COMPANY | SHERIDAN | 2002-12-27 | – | yes |
| 307-707 | UNION TELEPHONE COMPANY | GREENRIVER | 2003-06-26 | – | yes |
| 307-708 | UNION TELEPHONE COMPANY | EVANSTON | 2003-06-16 | – | yes |
| 307-709 | UNION TELEPHONE COMPANY | RIVERTON | 2003-06-16 | – | yes |
| 307-710 | UNION TELEPHONE COMPANY | RAWLINS | 2003-06-16 | – | yes |
| 307-712 | UNION TELEPHONE COMPANY | CODY | 2002-12-27 | – | yes |
| 307-713 | UNION TELEPHONE COMPANY | JACKSON | 2003-06-16 | – | yes |
| 307-714 | UNION TELEPHONE COMPANY | LANDER | 2003-06-16 | – | yes |
| 307-715 | UNION TELEPHONE COMPANY | TORRINGTON | 2002-12-27 | – | yes |
| 307-716 | UNION TELEPHONE COMPANY | POWELL | 2002-12-27 | – | yes |
| 307-717 | UNION TELEPHONE COMPANY | DOUGLAS | 2002-12-27 | – | yes |
| 307-718 | UNION TELEPHONE COMPANY | WORLAND | 2002-12-27 | – | yes |
| 307-719 | UNION TELEPHONE COMPANY | BUFFALO | 2002-12-27 | – | yes |
| 307-720 | UNION TELEPHONE COMPANY | WHEATLAND | 2002-12-27 | – | yes |
| 307-721 | Lumen | LARAMIE | – | – | yes |
| 307-722 | UNION TELEPHONE COMPANY | THERMOPOLS | 2002-12-27 | – | yes |
| 307-723 | UNION TELEPHONE COMPANY | KEMMERER | 2003-06-16 | – | yes |
| 307-724 | UNION TELEPHONE COMPANY | CASPER | 2003-06-16 | – | yes |
| 307-727 | UNION TELEPHONE COMPANY | KEMMERER | – | – | yes |
| 307-728 | UNION TELEPHONE COMPANY | SHOSHONI | – | – | yes |
| 307-730 | UNION TELEPHONE COMPANY | JACKSON | – | – | yes |
| 307-731 | UNION TELEPHONE COMPANY | LOVELL | 2002-12-27 | – | yes |
| 307-732 | Lumen | JACKSON | – | – | yes |
| 307-733 | Lumen | JACKSON | – | – | yes |
| 307-734 | Lumen | JACKSON | – | – | yes |
| 307-735 | Lumen | GLENDO | – | yes | yes |
| 307-736 | RANGE TEL COOP INC | ARVADA | – | – | yes |
| 307-737 | RANGE TEL COOP INC | SOUTHESRDN | – | – | yes |
| 307-738 | RT COMMUNICATIONS | KAYCEE | – | – | yes |
| 307-739 | Lumen | JACKSON | – | – | yes |
| 307-740 | UNION TELEPHONE COMPANY | JACKSON | – | – | yes |
| 307-741 | UNION TELEPHONE COMPANY | GLENROCK | 2002-12-27 | – | yes |
| 307-742 | Lumen | LARAMIE | – | – | yes |
| 307-744 | UNION TELEPHONE COMPANY | NEWCASTLE | 2002-12-27 | – | yes |
| 307-745 | Lumen | LARAMIE | – | – | yes |
| 307-746 | RT COMMUNICATIONS | NEWCASTLE | – | yes | yes |
| 307-747 | UNION TELEPHONE COMPANY | MT VIEW | 2003-06-16 | – | yes |
| 307-749 | UNION TELEPHONE COMPANY | PINEDALE | 2003-10-20 | – | yes |
| 307-750 | RANGE TEL COOP INC | DECKER | – | – | yes |
| 307-751 | AT&T | SHERIDAN | – | yes | yes |
| 307-752 | Verizon | SHERIDAN | – | – | yes |
| 307-754 | Lumen | POWELL | – | – | yes |
| 307-755 | Lumen | LARAMIE | – | – | yes |
| 307-756 | RT COMMUNICATIONS | MOORCROFT | – | yes | yes |
| 307-757 | Verizon | CHEYENNE | – | yes | yes |
| 307-758 | RANGE TEL COOP INC | CLEARMONT | – | – | yes |
| 307-759 | UNION TELEPHONE COMPANY | LUSK | 2003-10-20 | – | yes |
| 307-760 | Verizon | LARAMIE | – | – | yes |
| 307-761 | AT&T | LARAMIE | – | yes | yes |
| 307-762 | TRI-COUNTY TEL. ASSN., INC. | BURLINGTON | – | – | yes |
| 307-763 | Verizon | SHERIDAN | – | yes | yes |
| 307-764 | TRI TEL, INC. | POWELL | 2005-04-01 | – | yes |
| 307-765 | TRI-COUNTY TEL. ASSN., INC. | GREYBULL | – | – | yes |
| 307-766 | Lumen | LARAMIE | – | – | yes |
| 307-770 | ALL WEST/WYOMING, INC. | FARSON | 2020-05-07 | yes | yes |
| 307-771 | Lumen | CHEYENNE | – | – | yes |
| 307-772 | Lumen | CHEYENNE | – | yes | yes |
| 307-773 | Lumen | CHEYENNE | – | – | yes |
| 307-774 | AT&T | JACKSON | 2005-06-22 | – | yes |
| 307-775 | Lumen | CHEYENNE | – | – | yes |
| 307-776 | Vonage | CASPER | 2018-03-09 | yes | yes |
| 307-777 | Lumen | CHEYENNE | – | – | yes |
| 307-778 | Lumen | CHEYENNE | – | – | yes |
| 307-779 | UNION TELEPHONE COMPANY | WHEATLAND | 2003-10-20 | – | yes |
| 307-780 | UNION TELEPHONE COMPANY | MT VIEW | – | – | yes |
| 307-782 | UNION TEL. CO. | MT VIEW | – | – | yes |
| 307-783 | Lumen | EVANSTON | – | – | yes |
| 307-785 | Onvoy | WBLLFOURCH | 2017-04-19 | yes | yes |
| 307-786 | UNION TEL. CO. | URIE | – | – | yes |
| 307-787 | UNION TEL. CO. | LYMAN | – | – | yes |
| 307-788 | Lumen | WEST LYMAN | – | yes | yes |
| 307-789 | Lumen | EVANSTON | – | – | yes |
| 307-790 | UNION TELEPHONE COMPANY | SUNDANCE | 2003-12-18 | – | yes |
| 307-797 | AT&T | CASPER | 2001-10-03 | yes | yes |
| 307-798 | UNION TELEPHONE COMPANY | ROCK RIVER | 2007-11-06 | – | yes |
| 307-799 | UNION TELEPHONE COMPANY | EVANSTON | – | – | yes |
| 307-800 | Onvoy | KEMMERER | 2012-11-19 | yes | yes |
| 307-823 | AT&T | CHEYENNE | 2012-08-01 | yes | yes |
| 307-828 | Lumen | KEMMERER | – | yes | yes |
| 307-829 | Lumen | CHEYENNE | 2014-11-21 | yes | yes |
| 307-834 | Lumen | LA GRANGE | – | yes | yes |
| 307-836 | Lumen | GUERNSEY | – | yes | yes |
| 307-837 | Lumen | LINGLE | – | yes | yes |
| 307-840 | Verizon | RIVERTON | – | yes | yes |
| 307-849 | Lumen | BORDER | – | – | yes |
| 307-850 | UNION TELEPHONE COMPANY | RIVERTON | – | – | yes |
| 307-851 | Verizon | RIVERTON | – | – | yes |
| 307-854 | ADVANCED COMMUNICATIONS TECHNOLOGY, INC. - WY | RIVERTON | 2007-12-10 | yes | yes |
| 307-855 | Lumen | RIVERTON | – | yes | yes |
| 307-856 | Lumen | RIVERTON | – | – | yes |
| 307-857 | Lumen | RIVERTON | – | yes | yes |
| 307-858 | UNION TELEPHONE COMPANY | RIVERTON | – | – | yes |
| 307-859 | Lumen | DANIEL | – | yes | yes |
| 307-864 | RT COMMUNICATIONS | THERMOPOLS | – | – | yes |
| 307-867 | TRI-COUNTY TEL. ASSN., INC. | HAMITNDOME | – | – | yes |
| 307-868 | TRI-COUNTY TEL. ASSN., INC. | MEETEETSE | – | – | yes |
| 307-870 | UNION TELEPHONE COMPANY | GREENRIVER | – | – | yes |
| 307-871 | Verizon | GREENRIVER | – | – | yes |
| 307-872 | Lumen | GREENRIVER | – | – | yes |
| 307-874 | UNION TEL. CO. | MANILA | – | – | yes |
| 307-875 | Lumen | GREENRIVER | – | – | yes |
| 307-876 | RT COMMUNICATIONS | SHOSHONI | – | – | yes |
| 307-877 | Lumen | KEMMERER | – | yes | yes |
| 307-878 | RANGE TEL COOP INC | SO ALZADA | – | – | yes |
| 307-880 | GOLD STAR COMMUNICATIONS, LLC | FREEDOM | 2005-06-22 | – | yes |
| 307-881 | ADVANCED COMMUNICATIONS TECHNOLOGY, INC. - WY | WHEATLAND | 2014-11-21 | yes | yes |
| 307-883 | SILVER STAR TEL CO INC | FREEDOM | – | – | yes |
| 307-884 | UNION TELEPHONE COMPANY | AFTON | – | – | yes |
| 307-885 | SILVER STAR TEL CO INC | AFTON | – | – | yes |
| 307-886 | Lumen | AFTON | – | yes | yes |
| 307-887 | GOLD STAR COMMUNICATIONS, LLC | AFTON | 2005-06-22 | – | yes |
| 307-888 | Telnyx | OLDFATHFUL | 2017-02-22 | yes | yes |
| 307-890 | UNION TELEPHONE COMPANY | FREEDOM | – | – | yes |
| 307-895 | Twilio | CHEYENNE | 2022-03-31 | yes | yes |
| 307-896 | Lumen | WBLLFOURCH | – | – | yes |
| 307-899 | AT&T | CODY | – | – | yes |
| 307-900 | FRACTEL, LLC | GLENDO | 2020-06-10 | yes | yes |
| 307-910 | Onvoy | CHEYENNE | 2021-04-23 | yes | yes |
| 307-920 | T-Mobile | CHEYENNE | – | yes | yes |
| 307-921 | Verizon | THERMOPOLS | – | yes | yes |
| 307-922 | Verizon | ROCK SPG | – | yes | yes |
| 307-939 | Lumen | WRIGHT | – | yes | yes |
| 307-941 | Verizon | NEWCASTLE | – | yes | yes |
| 307-949 | Verizon | NEWCASTLE | – | yes | yes |
| 307-977 | UNION TELEPHONE COMPANY | LARAMIE | – | – | yes |
| 307-990 | COMMIO, LLC | LANDER | 2023-04-04 | yes | yes |
| 307-995 | Lumen | CASPER | – | yes | yes |
| 307-996 | Onvoy | CHEYENNE | – | yes | yes |
| 307-998 | Onvoy | SHERIDAN | 2024-06-14 | yes | yes |
| 307-999 | Telnyx | MORAN | 2017-02-28 | yes | yes |
Frequently asked
How many prefixes does area code 307 have?
499 NXX blocks are assigned of 786 possible. Each block is 10,000 consecutive numbers, so the code currently covers about 4,990 thousand-number ranges across 92 rate centers.
What do the first three digits after 307 tell me?
They identify the block, which tells you the rate center it was allocated to and the carrier that received it. They do not tell you who serves the number today: portability moves numbers between carriers, and pooling splits a block between several of them.
Is a 307 prefix tied to a specific town?
To a rate center, which is billing geography rather than a town. NANPA abbreviates rate center names to ten characters and in large metros uses zone codes, so the name is a NANPA label, not a place name.
What does “pooled” mean in the 307 table?
That the block is in thousands-block pooling: carriers draw 1,000-number lots from it instead of taking all 10,000. 279 of 307's blocks are pooled, which is how regulators slowed down area code exhaustion – and why one prefix can belong to several carriers.
Source and limits
NANPA CO Code Assignment Records, all states, utilized codes, file updated 11/01/2026 – the rows where the record's Use field is “AS” (assigned). Unavailable codes are excluded. The records say who received a block and when, not who serves a particular number today.
More about this code: overview · carriers · spam complaints · local time