Diesel prices along
I-15.
I-15 runs south to north from San Diego to the Canadian border in Montana, crossing 6 states. Right now the cheapest median on the corridor is $5.60/gal in Montana and the most expensive is $7.86/gal in California, a $2.26/gal gap.
Data window: last 7 days · 1,488 observations · 720 truck stops on I-15
Where the cheap stops fall
Fuel in Montana, state 6 of 6 running south to north.
Running I-15 south to north, Montana is where the median drops lowest. A 250-gallon fill there runs about $565 less than the same fill in California, on one truck, on one fill, before any negotiated discount is applied.
State medians tell you which state to lean on. Which station, how many gallons, and whether the tank can make it there is what ValveRide Flow works out per dispatch, with your contract rates and state fuel-tax differences layered on top of the posted price.
State by state
I-15 diesel prices, California to Montana
States in road order, south to north. Cheap and expensive are the 10th and 90th percentile of tracked stations in each state; spread is the gap between them, and a wider spread means more room for a routed fleet to save inside that state.
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Questions, answered
I-15 diesel prices, explained.
Where is diesel cheapest along I-15 right now?
The lowest median diesel price on I-15 is $5.60 per gallon in Montana, across 56 tracked truck stops. The cheapest 10% of stations anywhere on the corridor are at or below $5.40/gal, in Montana.
Which states on I-15 have the most expensive diesel?
California has the highest median on I-15 at $7.86/gal, $2.26 above Montana. On a 250-gallon fill that gap is about $565 between the two states, before any negotiated discount.
How much does diesel cost along I-15 today?
State medians along I-15 currently range from $5.60 in Montana to $7.86 in California, based on 1,488 price observations from 720 truck stops in the last 7 days. Prices are pump-posted retail, not contract rates.
Prices are pump-posted retail percentiles from tracked truck stops in the 48 contiguous states, never contract or discounted rates. Methodology and the full state table live on the national diesel prices page.
Connecting corridors
Other interstates that share a state with I-15
All corridors: diesel prices by interstate. Origin-to-destination view: diesel prices by lane.
Your trucks run I-15.
Flow makes every fill count.
Live prices, your negotiated contracts, and state fuel-tax math, applied automatically on every dispatch, with every claimed dollar reconciled against a real transaction.