Cheyenne, WY Area Code

Area code serving Cheyenne

Cheyenne sits in Wyoming, part of the West region and the Mountain Time zone. Its area code is 307, which covers the entire state of Wyoming. 307 has no overlay today, so every Cheyenne landline and mobile number with a local code starts with 307.

307 has served the area since 1947. If the region runs low on numbers, regulators will most likely add an overlay code on top rather than split the area, which would make 10-digit dialing mandatory.

Code	Area served	In service
307	The entire state of Wyoming	January 1, 1947

Nearby cities sharing this area code

• Casper
• Gillette
• Laramie
• Rock Springs
• Sheridan
• Green River
• Evanston
• Riverton
• Jackson
• Cody
• Rawlins
• Lander
• Torrington

Getting a Cheyenne phone number

Any new landline, mobile or VoIP number from a local carrier in Cheyenne gets the 307 area code. Numbers come from the blocks each carrier holds in the area; a number ported in from elsewhere keeps its original area code, so you may also see out-of-state codes locally.

Dialing in Cheyenne

Cheyenne is covered by the single area code 307 with no overlay, so some local calls may still connect with seven digits. Dialing all 10 digits (area code + seven-digit number) always works and is the safest habit. From outside the US, dial +1, then the area code and number. See 10-digit dialing and overlay area codes for the background. For every code in Wyoming, visit the Wyoming area codes page.