Gas prices in Idaho
Regular gas costs an average of $4.49 a gallon in Idaho, and diesel $6.41, based on the Rocky Mountain regional figure for the week of September 28, 2026. That's 2 cents above the national average.
EIA doesn't publish a separate average for Idaho, so this is the Rocky Mountain average, which covers Idaho. Prices at individual stations vary.
| Fuel | Idaho | U.S. average |
|---|---|---|
| Regular | $4.49 | $4.47 |
| Diesel | $6.41 | $6.38 |
What gas costs in Idaho
Filling a 15-gallon tank with regular costs about $67.35. A 300-mile road trip in a car that gets 25 mpg uses 12 gallons, which comes to about $53.88.
Frequently asked questions
How much is gas in Idaho right now?
Regular gas averages $4.49 a gallon based on the Rocky Mountain regional figure for the week of September 28, 2026.
How much is diesel in Idaho?
Diesel averages $6.41 a gallon based on the Rocky Mountain figure.
How much does it cost to fill up in Idaho?
A 15-gallon tank of regular costs about $67.35 at the average price.
Where do these prices come from?
The U.S. Energy Information Administration surveys retail gas stations every week and publishes averages for the nation, regions and nine states every Monday.
Gas prices in Rocky Mountain over time
Since 6 October 2025, the typical price of regular gas has risen by 142 cents.
Weekly averages from the U.S. Energy Information Administration. See national price history.
Gas prices in other states
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida
- Georgia
- Hawaii
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming