307 Area CodeCheyenne, WY
Area code 307 covers Cheyenne and nearby communities in Wyoming, in the Mountain Time (MT) zone, home to about 457,000 people across 203 cities. It's the only area code for this region, so the three digits alone place the caller.
Overview
- Major City
- Cheyenne
- State
- Wyoming (WY)
- Timezone
- Mountain Time (MT)
- Current Time
- Overlay
- No – unique area code
Where is area code 307?
Area code 307 serves part of Cheyenne, WY and the surrounding areas. It is a unique area code with no overlays.
Overview of the 307 Area Code
What is the 307 area code?
The 307 area code serves Cheyenne, Wyoming. When you see a 307 number, it indicates a local number within this geographic area.
Why was area code 307 created?
The 307 area code was established to serve the Cheyenne region in Wyoming. It provides telephone number coverage across 203 cities.
Geographic Coverage of the 307 Area Code
The 307 area code serves Cheyenne and surrounding areas in Wyoming. It operates within the Mountain Time (MT) time zone. This area code covers several key cities, including:
- Cheyenne
- Casper
- Gillette
- Laramie
- Rock Springs
- Sheridan
Got a call from a 307 number? It came from Cheyenne, WY. No other area code overlaps the 307 territory, so the prefix alone identifies where the caller is. Inside 307, Cheyenne holds about 14% of the population; the rest is split across 202 smaller cities.
Cheyenne Area Code Overview
The 307 area code provides comprehensive telephone coverage for Cheyenne and its surrounding communities. As the sole area code for this region, it uniquely identifies all local numbers within the service area.
What cities does area code 307 cover?
| City | State | Population | % of Area Code | % of City |
|---|---|---|---|---|
| Cheyenne | WY | 65,704 | 0% | 100% |
| Casper | WY | 58,823 | 0% | 100% |
| Gillette | WY | 33,846 | 0% | 100% |
| Laramie | WY | 32,957 | 0% | 100% |
| Rock Springs | WY | 22,967 | 0% | 100% |
| Sheridan | WY | 19,813 | 0% | 100% |
| Evanston | WY | 11,691 | 0% | 100% |
| Green River | WY | 11,474 | 0% | 100% |
| Riverton | WY | 10,953 | 0% | 100% |
| Jackson | WY | 10,680 | 0% | 100% |
* Sources: Population – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). Area code assignments – NANPA CO Code data. See our data methodology.
Has area code 307 been reported for unwanted calls?
Yes – 622 unwanted-call complaints were reported to the FTC for numbers showing a 307 area code (May 29 – Jul 2, 2026).
- 76% robocalls
- ↓ 20% vs prior period
Most-reported subjects
- Reducing your debt (credit cards, mortgage, student loans)41%254
- Other39%245
- Calls pretending to be government, businesses, or family and friends5%28
* Caller ID is easily spoofed, so these figures reflect the number shown on caller ID, not the caller's true location – an area code alone never identifies a caller. The FTC does not verify the facts in these complaints. Source: FTC Do Not Call (DNC) Reported Calls Data, retrieved 2026-07-05.
Which prefixes and exchanges belong to area code 307?
46% assigned to a telco
- 76% Landline
- 24% Wireless
- 0% Unknown
| Prefix | Usage | Carrier |
|---|---|---|
| (307)200- | Landline | Level 3 Communications |
| (307)201- | Landline | Level 3 Communications |
| (307)202- | Wireless | New Cingular Wireless Pcs |
| (307)203- | Wireless | T-Mobile Usa |
| (307)204- | Landline | Airus |
| (307)205- | Landline | Level 3 Communications |
| (307)206- | Landline | Mcimetro Access Transmission Services |
| (307)207- | Landline | Airus |
| (307)209- | Wireless | Verizon Wireless |
| (307)210- | Wireless | New Cingular Wireless Pcs |
Frequently Asked Questions about the 307 Area Code
Who called me from a 307 number?
A 307 number is assigned to Cheyenne, Wyoming, so a call may come from there. But caller ID is easy to fake, and scammers often spoof a local 307 code to look nearby, so a 307 number doesn't prove the caller is local. Recently, 622 unwanted-call complaints were reported to the FTC for numbers showing the 307 code (76% flagged as robocalls). If you don't recognize the number, let it go to voicemail; a real caller will leave a message.
Is 307 a scam area code?
No area code is a scam on its own. 307 is a normal, officially assigned code for Cheyenne, Wyoming. Spam callers spoof local codes to raise the odds you answer, so 307 on your caller ID says nothing about who is really calling. Recently, 622 unwanted-call complaints were reported to the FTC for numbers showing the 307 code (76% flagged as robocalls). Judge the call itself, not the area code.
Why do I keep getting calls from the 307 area code?
Repeated calls from different 307 numbers are usually spoofing: a robocaller rotates through 307 numbers so each call looks local and slips past simple blocks. Recently, 622 unwanted-call complaints were reported to the FTC for numbers showing the 307 code (76% flagged as robocalls). Blocking one number rarely helps; voicemail screening, your carrier spam filter, and the Do Not Call Registry work better.
Should I answer an unknown 307 number?
If you aren't expecting a 307 call, let it ring to voicemail. Legitimate callers leave a message, most robocallers hang up when no one picks up, and answering can mark your number as active and bring more calls.
How do I block calls from the 307 area code?
Block a single 307 number from your recent-calls list (iPhone: tap the number, then Block this Caller; Android: tap the number, then Block or report spam). To cut the volume, turn on Silence Unknown Callers on iPhone or spam protection on Android, enable spam filtering from your carrier, and register at DoNotCall.gov. Blocking the entire 307 code also stops legitimate local calls, so use it only as a last resort.
Where is area code 307?
Area code 307 covers Cheyenne and the surrounding area in Wyoming, spanning 203 cities with about 457,017 residents. No other code overlays this region, so 307 alone identifies the area.
Is 307 a real area code?
Yes. 307 is an active code in the North American Numbering Plan, assigned by NANPA and in service for Cheyenne, Wyoming. A real code can still show up on spoofed spam calls, so treat unknown 307 calls with normal caution.
What timezone is the 307 area code in?
The 307 area code is in the Mountain Time (MT). Because a number can be kept when someone moves or switches to VoIP, a specific 307 caller may not be in that zone.
How do I call a 307 number from abroad?
From outside the US, dial your country's exit code, then 1 (the US country code), then 307 and the seven-digit number. From a mobile phone you can usually just enter +1 307 followed by the number and let the phone add the exit code for you.