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Before You Call Back

Area code 307

Area code 307 serves Wyoming, including Cheyenne, Casper and Gillette (Mountain time). It has been in service since January 1, 1947.

Numbers starting with 307 drew 992 reports to the FTC from Aug 14, 2026 to Nov 11, 2026 and 546 complaints to the FCC since November 2023. The number on your screen can be faked, so a 307 number proves nothing about where a call came from.

Location
Wyoming
Time zone
Mountain
In service since
January 1, 1947
Overlay
None: the only code for its area
Local calls
Dial 7 digits
Exchanges in use
499 of 792held by 51 carriers
Projected to run out
2Q 2056NANPA forecast 2026.2

Complaints about 307 numbers

Reports where the number on the consumer's caller ID (or, for the FCC, the number the caller asked them to call back) starts with 307. These are counts of what people reported; the agencies do not verify them.

FTC reports, Aug 14, 2026 to Nov 11, 2026

992

FCC complaints since November 2023

546

Different 307 numbers reported

1,406

FCC complaints naming a 307 number, by month

November 2023 to October 2026. Source: FCC Consumer Complaints Data.

Show as a table
MonthComplaints
November 20238
December 20237
January 202413
February 20243
March 20245
April 202414
May 202410
June 202410
July 202417
August 202416
September 202412
October 202413
November 202421
December 20244
January 202524
February 202524
March 202514
April 202510
May 202511
June 202516
July 20259
August 202511
September 20259
October 20250
November 20253
December 20257
January 202648
February 202617
March 202619
April 202620
May 20268
June 202619
July 202648
August 202622
September 202617
October 202624

What people said 307 calls were about

Subjects picked in FTC reports, August 14, 2026 to November 11, 2026. 581 of 992 reports were robocalls.

Show as a table
SubjectReports
Other434
Reducing your debt (credit cards, mortgage, student loans)280
Calls pretending to be government, businesses, or family and friends53
Dropped call or no message44
Medical and prescriptions25
Home improvement and cleaning17

Places served by 307

NANPA lists 92 rate centers for 307. A rate center is the town or district a block of numbers is tied to for billing; sorted here by how many exchanges each holds.
  • Cheyenne60
  • Casper40
  • Gillette21
  • Jackson21
  • Laramie18
  • Rock Springs17
  • Sheridan17
  • Cody15
  • Evanston13
  • Riverton13
  • Lander11
  • Green River10
  • Powell10
  • Buffalo9
  • Douglas9
  • Rawlins9
  • Afton8
  • Wheatland8
  • Pinedale7
  • Torrington7
  • Kemmerer6
  • Lusk6
  • Newcastle6
  • Sundance5
Show all 92 rate centers

Worland, Big Piney, Border, Cokeville, Freedom, Glenrock, Hanna, Lagrange, Lake, Moran, Mountain View, Old Faithful, Thermopolis, West Spearfish, Baggs, Dubois, Farson, Jeffrey City, La Barge, Lingle, Lyman, Mammoth, Medicine Bow, Saratoga, Shoshoni, West Belle Fourche, Wright, Alpine, Basin, Burns, Daniel, Glendo, Greybull, Guernsey, Hamilton Dome, Lovell, Midwest, Moorcroft, Rock River, Shirley Basin, Southeast Sheridan, Upton, Urie, Albin, Alta, Arvada, Burlington, Carpenter, Chugwater, Clark, Clearmont, Crowheart, Decker, Encampment, Frannie, Gas Hills, Hulett, Hyattville, Kaycee, Leigh Canyon, Manila, Meeteetse, Pine Bluffs, South Alzada, South Wyola, Ten Sleep, West Edgemont, West Lyman.

Phone companies holding 307 exchanges

Each exchange (the three digits after the area code) is assigned to one carrier. 56% of these exchanges are pooled: their numbers are handed out in blocks of 1,000 to other carriers, so the holder below is not always the company serving a given number.

Exchanges held, top 8 of 51 carriers

NANPA central office code assignments, file of November 11, 2026.

Show as a table
Carrier (legal name)Exchanges
Qwest Corporation83
Union Telephone Company65
Cellco Partnership dba Verizon Wireless - WY60
New Cingular Wireless PCS, LLC49
Onvoy, LLC - WY40
Level 3 Communications, LLC - WY27
Bandwidth.com CLEC, LLC - WY19
Rt Communications17

When today's 307 exchanges were assigned

Exchanges still assigned, by year of assignment. Exchanges returned since are not counted.

Show as a table
YearExchanges
20016
200229
200322
200410
20058
20066
20076
20084
20092
20103
20115
20123
20132
20146
20156
20162
20177
20188
201911
202016
202126
20226
202316
20249
20259
20266

Check a 307 number

A check shows the carrier and rate center of the number's exchange and every FTC and FCC report about that exact number. Why the number on screen can be fake.

NANPA area code database and central office code file of November 11, 2026; FCC complaints November 1, 2023 to November 11, 2026; FTC reports August 14, 2026 to November 11, 2026. How the data is used.

Official sources (7)Show