Area Code 307: Cheyenne, Wyoming
307 is a telephone area code serving Wyoming, including Cheyenne, Casper. It is part of the North American Numbering Plan and is dialed with the country code +1.
Numbers beginning with 307 are located in Wyoming, United States (NANP region: Statewide). The code covers Cheyenne, Casper.
How to Dial Area Code 307
| Calling from | What to dial |
|---|---|
| Anywhere in the US or Canada | 1 307 XXX-XXXX (10-digit dialing: 307 + 7-digit number) |
| Local call inside the same area code | 7-digit number in most areas; 10 digits where an overlay code is active |
| From the UK or Europe | 00 1 307 XXX XXXX |
| From Australia | 0011 1 307 XXX XXXX |
| From a mobile phone anywhere | +1 307 XXX XXXX |
Whatever country you are calling from, the + symbol replaces the exit code. Save the contact as +1 307 XXXXXXX and it will dial correctly from any phone in the world.
Time Zone for Area Code 307
Calls to a 307 number ring in the America/Denver time zone, standard offset UTC-07:00. Daylight saving time applies here, so the offset moves forward one hour from March to November.
Cities and Communities Served by 307
The following places fall inside the 307 calling area:
Other Area Codes in Wyoming
These codes also serve Wyoming. Area codes are assigned by the North American Numbering Plan Administration (NANPA).
| Area Code | Cities / Coverage |
|---|
See all 1 area codes in Wyoming →
Frequently Asked Questions
Where is area code 307?
Area code 307 is in Wyoming, United States. It covers Cheyenne, Casper.
What time zone is area code 307 in?
Area code 307 rings in the America/Denver time zone (UTC-07:00 standard).
Do I need to dial 1 before area code 307?
Yes, for a long-distance call inside the US and Canada you dial 1 first, then 307, then the seven-digit number. The 1 is the North American long-distance trunk prefix — it is not the country code. From outside North America you dial your exit code then 1 then 307.
Is area code 307 toll-free?
No. 307 is a standard geographic area code, so normal long-distance rates apply unless your plan includes them. Toll-free NANP codes are 800, 833, 844, 855, 866, 877 and 888.