Boise gas prices to spike ‘just before Memorial Day.’ What you’ll pay
If you’re planning a road trip for Memorial Day weekend, be ready for higher prices at the pump.
Gas experts say drivers could face some of the most expensive fuel prices of the year as summer travel season begins.
In 2026, Memorial Day falls on Monday, May 25, marking the unofficial start of summer across Idaho, according to The Old Farmer’s Almanac.
Though gas prices have already been rising across the country since the start of the war in Iran, the “next gas price spike could arrive just before Memorial Day,” according to price-tracking website GasBuddy.
Global oil supply remains tight, meaning gas prices could rise even more if tensions worsen or supplies are disrupted, according to Patrick De Haan, head of petroleum analysis at GasBuddy.
“As a result, gasoline and diesel prices are likely to remain volatile, and with Memorial Day approaching, any sustained increase in oil prices could begin pushing retail fuel prices higher again in the weeks ahead,” Da Haan said in a Monday, May 18, news release.
How much can Idaho drivers expect to pay for gas?
Here’s what to know:
What are current gas prices in Idaho?
As of Thursday, May 21, Idaho was No. 11 on AAA’s list of the U.S. states with the most expensive gas.
The average price for a gallon of regular gas in Idaho was about $4.69 as of Thursday, with per-gallon averages in some Idaho counties topping $5, according to AAA.
That’s roughly 13 cents more than the national average of $4.56 per gallon.
“The national average is at the same range as it was in 2022, the year gas prices hit record highs,” AAA said in a May 14 news release.
In July 2022, Idaho’s average price for regular gasoline climbed to a record high of $5.25 per gallon during the start of the Russian-Ukraine War.
“Travelers are preparing to hit the road in record numbers next week, and drivers will be facing the highest Memorial Day gas prices in four years,” AAA said in the news release.
How much does gas cost in my Idaho city?
As of Thursday, May 21, these were the average per-gallon prices for regular gasoline at cities across Idaho:
- Boise: $4.69 a gallon
- Coeur D’Alene: $4.60
- Idaho Falls: $4.65
- Lewiston: $4.58
- Pocatello: $4.68
- Twin Falls: $4.72
Which Idaho counties have the most expensive gas?
According to AAA, these were Idaho’s top 10 most expensive counties to fill up as of Thursday, May 21:
- Boise County: $5.10 per gallon
- Clark: $5.09
- Camas: $5.03
- Fremont: $4.921
- Shoshone: $4.88
- Blaine: $4.874
- Butte: $4.872
- Cluster: $4.82
- Lemhi: $4.81
- Valley: $4.80
Where is the most affordable gas in Idaho?
As of Thursday, these Idaho counties had the lowest prices for regular gas, AAA said:
- Nez Perce: $4.57
- Kootenai: $4.60
- Bonner: $4.62
- Bonneville: $4.63
- Franklin: $4.63
- Power: $4.65
- Gem: $4.66
- Madison: $4.67
- Bannock: $4.68
- Jefferson: $4.68
How to find cheapest gas stations
GasBuddy is designed to help motorists find the cheapest gas prices in their areas.
You can search for the most affordable gas stations in your area on the GasBuddy website.
Why is gas so expensive in Idaho?
Idaho gas prices have been steadily rising since late February as tensions in the Middle East increased and concerns about global oil supplies grew.
Since then, prices have climbed by more than $1.50 a gallon, bringing the state close to the record-breaking fuel prices seen in 2022.
Diesel prices have also surged.
As of Thursday, Idaho’s average diesel price hit a record $5.64 per gallon.
This story was originally published May 21, 2026 at 10:22 AM with the headline "Boise gas prices to spike ‘just before Memorial Day.’ What you’ll pay."
