Area Code 307
Area code 307 covers Cheyenne and nearby cities including Casper, Gillette, Laramie in Wyoming, in the Mountain Time.
Area code 307 quick facts
| Location | Cheyenne, Wyoming |
|---|---|
| Time zone | Mountain Time |
| In service | 1947-01-01 |
| Nearby codes | 748, 970, 303, 720, 983, 719 |
| Carrier coverage | 497 prefixes; 35% wireless |
| FTC complaint data | 350 complaints across 85 numbers |
| Data current as of | August 2, 2026 |
Is a call from 307 a scam? Who called me from 307?
FTC complaints involving 307 numbers
Numbers shown with area code 307 in the FTC's Do Not Call “Reported Calls” database (recent reporting window). Most common reported reasons: “Other”, “Reducing your debt (credit cards, mortgage, student loans)”, “No Subject Provided”.
Most-complained 307 numbers:
- (307) 200-4080 — 19 complaints
- (307) 355-3654 — 12 complaints
- (307) 212-6410 — 10 complaints
- (307) 224-6687 — 9 complaints
- (307) 683-0237 — 8 complaints
These are FTC Do Not Call complaints filed about specific numbers shown with this area code — frequently spoofed. The area code itself is not a scam. See the most-reported area codes and the most-reported phone numbers nationwide.
Cities in area code 307
Cheyenne, Casper, Gillette, Laramie
Area codes by city
Carriers in area code 307
Area code 307 spans 497 prefixes, about 35% wireless. Top carriers: ONVOY, LLC - WY, CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY, NEW CINGULAR WIRELESS PCS, LLC, QWEST CORPORATION. Look up the carrier and line type for a 307 number.
Nearby area codes
Frequently asked questions
Where is area code 307?
Area code 307 covers Cheyenne and nearby cities including Casper, Gillette, Laramie in Wyoming, in the Mountain Time.
What cities use area code 307?
Area code 307 serves Cheyenne, Casper, Gillette, Laramie in Wyoming.
What time zone is area code 307 in?
Area code 307 is in the Mountain Time (America/Denver).
How do you dial a 307 number?
Dial all 10 digits: 307 followed by the 7-digit local number. From abroad, dial +1 307 and the local number.
Is a call from area code 307 a scam?
A 307 number is geographically tied to Wyoming, but caller ID can be spoofed, so the displayed area code does not prove where a caller really is. If you did not expect the call, do not share personal information and consider looking the number up.
Is 307 a country code?
No. 307 is a US area code (a domestic 3-digit code), not a country code. The country (calling) code for the United States is +1, shared across the North American Numbering Plan. So a full 307 number written for international dialing looks like +1 307 followed by the 7-digit local number.
Sourced from the official NANPA (North American Numbering Plan Administrator) numbering database, current as of August 2, 2026. Refreshed monthly.