Stations in Illinois range from $4.80 at the cheap end to $5.40 at the expensive end. On a single 250-gallon tractor fill, the difference between a cheap-end station and a median-priced one is about $61 — on one fill, for one truck, before any negotiated discount is applied.
That spread is exactly where fuel optimization earns its keep: ValveRide Flow routes every dispatch to the right stop for the route, applies your negotiated contract rates on top of the posted price, and accounts for state fuel-tax differences so the net cost — not the pump sign — drives the decision.
Get a free, engine-generated fuel plan for any origin and destination — where to stop, how many gallons, at what price, with Illinois's live pricing baked in. In your inbox in about two minutes. No account needed.
Diesel runs $0.34/gal cheaper at the median across the border in Missouri. On routes that cross, where the truck fuels changes the cost of the load.
The median diesel price in Illinois is $5.04 per gallon across 361 tracked truck stops (last 7 days, 580 price observations). The cheapest 10% of stations are at or below $4.80/gal, and the most expensive 10% are at or above $5.40/gal.
Illinois runs +$0.14/gal versus the national median of $4.90, making it the 25th most expensive of 49 states with data. Fleets routing through Illinois often save by timing fills in cheaper neighboring states where the route allows.
The spread between the cheap end and expensive end in Illinois is $0.60/gal right now. On a 250-gallon fill, choosing a cheap-end station over a median-priced one saves about $61 — before contract discounts and IFTA tax positioning, which is what ValveRide Flow layers on automatically for fleets.
Methodology, percentile definitions, and the full 50-state table live on the national diesel prices page.
Live prices, your negotiated contracts, and state fuel-tax math — applied automatically on every dispatch, with every claimed dollar reconciled against a real transaction.