Rocky Mountain (PADD 4) benchmark
Idaho Gas Prices
Regular gasoline, all formulations, including taxes · Week ending Oct 26, 2026
Regular gasoline · Oct 26, 2026
Rocky Mountain (PADD 4) regional average (state benchmark) average price per gallon
$4.458 −$0.010
vs. week earlier · -0.2%
+$0.189 vs U.S. average ($4.269)
- 4 weeks ago
- $4.486
- Year ago
- $2.972
- 52-week low
- $2.400
- 52-week high
- $4.590
5-year weekly trend
USD / gallonWeekly retail average, all formulations, including taxes. Source: U.S. Energy Information Administration. Latest available week: 2026-10-26.
All-time high
$5.000
Jul 4, 2022
All-time low (since 2000)
$1.090
Dec 24, 2001
What drivers in Idaho are paying this week
Idaho does not have a published weekly statewide average, so the reference number above is the Rocky Mountain (PADD 4) average of $4.458. That regional benchmark fell $0.010 week over week and is $0.189 above the national average of $4.269. Stations in Idaho typically trade within roughly 20 to 40 cents of the regional figure, depending on distance from the nearest terminal and local taxes.
Idaho keeps its fuel tax low, but the state has no refineries. Fuel is trucked in from Utah, Washington, and Montana, so prices in Boise and Coeur d’Alene can differ by 30 cents or more.
Why Idaho gas prices land where they do
- No in-state refineries; all supply is imported by pipeline and truck.
- Low state fuel tax partly offsets freight costs.
- Northern Idaho is supplied from Washington and is exposed to West Coast price spikes.
These are structural factors, not daily noise. They explain why Idaho tends to sit in the same part of the national price range week after week, even when the national average moves. For the general mechanics behind these forces, see our guide on how gas prices are set.
How Idaho compares
Neighboring states with a published weekly average give the clearest picture of the regional spread. The table below compares Idaho against those states and the national average.
| Market | Regular price | vs Idaho | Week change |
|---|---|---|---|
| Idaho | $4.458 | — | −$0.010 |
| Washington | $5.203 | +$0.745 | −$0.130 |
| U.S. average | $4.269 | −$0.189 | −$0.010 |
Ways to spend less on gas in Idaho
- Membership warehouses such as Costco, Sam’s Club, and BJ’s usually price 10 to 30 cents below nearby branded stations.
- Stations a few miles off the interstate are often cheaper than the first exit, because they pay less for land and rely on local traffic.
- Apps that show station-level prices are worth using for the last mile — our numbers give you the regional baseline, they give you the address.
- Keeping tires at the recommended pressure and removing roof racks can recover 3 to 6 percent of fuel economy, which is worth 10 to 20 cents a gallon at current prices.
Want a number instead of a rule of thumb? The commute cost calculator turns your own miles and MPG into a weekly and annual fuel bill, using the current Idaho price as the default.
How we source Idaho prices
Every figure on this page comes from the U.S. Energy Information Administration's weekly retail gasoline survey, which reports average retail prices in dollars per gallon including taxes. We rebuild the page every week after the survey is released, so the date on the price panel always matches the data behind it. We do not estimate missing state numbers; where the EIA does not publish a statewide series, we label the regional benchmark instead. Full details are in our methodology and data sources pages.
The bottom line for Idaho drivers
At the regional benchmark of $4.458 per gallon, a 12-gallon fill-up in Idaho costs about $53.50. Over a 15,000-mile year at 28 MPG, that implies roughly $2388 in fuel, before any local station discounts.
Idaho gas price FAQ
What is the average gas price in Idaho right now?
The U.S. Energy Information Administration does not publish a weekly statewide retail average for Idaho. The closest official benchmark is the Rocky Mountain (PADD 4) average, which was $4.458 per gallon for the week ending Oct 26, 2026. Local station prices in Idaho typically fall within roughly 20 to 40 cents of that regional figure.
Is gas cheaper in Idaho than the national average?
Idaho is compared against the Rocky Mountain (PADD 4) benchmark rather than a statewide number. The region averaged $4.458 versus the national average of $4.269, so Idaho stations are best described as tracking above the national figure.
Why are gas prices high in Idaho?
No in-state refineries; all supply is imported by pipeline and truck. Low state fuel tax partly offsets freight costs. Northern Idaho is supplied from Washington and is exposed to West Coast price spikes. These factors matter more than the national average in determining what local stations charge, because fuel markets are regional, not national.
Where can I find the cheapest gas in Idaho?
Station-level pricing is not part of the EIA dataset, so we do not publish a cheapest-station list. In practice, the lowest prices in Idaho are usually at membership warehouses, at high-volume stations on secondary roads rather than interstate exits, and at stations in lower-cost suburban counties. Use a station-level price app for the final address and our Idaho benchmark to judge whether the price you see is reasonable.
Will gas prices go down in Idaho?
Nobody can forecast a specific week with confidence. What can be said is mechanical: Idaho prices follow crude oil costs, regional refining capacity, seasonal fuel specifications, and local taxes. When crude falls and refineries run normally, prices usually follow within two to four weeks. When a refinery goes down or a hurricane threatens the Gulf Coast, the move can reverse within days.