Cheyenne, WY is currently using one area code which is area code 307. Area Code 307 covers the entire state of Wyoming and was the original area code assigned to Wyoming in 1947.
In addition to Cheyenne, WY area code 307 serves the larger cities and communities of Casper, Cheyenne, Cody, Evanston, Gillette, Green River, Jackson, Laramie, Rawlins, Riverton, Rock Springs and Sheridan in addition to many smaller communities throughout Wyoming.
Cheyenne, WY is located in Laramie County and observes the Mountain Time Zone. View our Times by Area Code tool.