Guides
US diesel, explained
How the numbers on this site actually work: the Monday DOE number, regional spreads, the pump-over-spot margin, cost per mile. Each guide is built on the same live data as the trackers, so the examples are real and current.
The DOE number and the surcharge
What is the DOE diesel price?
The DOE diesel price is the US average retail price of on-highway diesel that the Energy Information Administration surveys every week and posts as the price for Monday. It is the number almost every fuel surcharge in US trucking is written against, which is why the whole trade watches for it.
How fuel surcharges work
A fuel surcharge passes fuel-price risk from the carrier to the shipper. A schedule sets a base fuel price, then adds a set amount per mile for every increment the DOE diesel number sits above that base, at a stated miles-per-gallon figure.
Cost per mile: fuel math for an owner-operator
Fuel cost per mile is the diesel price per gallon divided by the truck's miles per gallon. At the DOE number for the week of Oct 5, 2026, $6.199 a gallon, a truck getting 6.5 mpg spends about 95.4 cents a mile on fuel.
Do diesel prices predict freight rates?
No. Diesel is a cost the fuel surcharge passes through, and truckload rates are set by how many trucks are chasing how many loads. From February to April 2026 the DOE number's monthly average rose 48 percent while Cass's truckload linehaul index, which leaves fuel out, rose 2.7 percent.
The price map
What are PADDs?
A PADD is a Petroleum Administration for Defense District, one of five regions the federal government groups the states into for petroleum data. EIA reports diesel prices by these districts, so reading a regional diesel number starts with the map.
Why the West Coast pays more
The West Coast pays the highest diesel prices in the country, and California the most of all. Three things drive it: a stricter state fuel spec, higher state taxes and fees, and a refining map that leaves the region supplying most of its own fuel.
Prices and how they move
Retail, rack and spot: the diesel price ladder
There is no single diesel price. A gallon carries a different number at each step from refinery to truck: a spot price at the trading hub, a rack price at the terminal, and the taxed retail price at the pump. Each sits above the last.
Why diesel costs more than gasoline
Diesel usually costs more than gasoline for four structural reasons: higher taxes, costlier refining to hit ultra-low sulfur, export demand and competition for the same middle-distillate barrel from heating oil and jet fuel.
Winter diesel: blends, gelling and the seasonal premium
Winter diesel is regular diesel treated or blended so it keeps flowing in the cold. Below a certain temperature the wax in diesel crystallizes, and if enough forms the fuel gels and stops passing through the filter, which is why northern diesel changes with the season and costs a little more. The basic, standard and premium labels at the pump are the seller's marketing, not grades in the fuel standard.
How do crude oil futures move diesel prices?
Crude oil futures move diesel prices indirectly: the main US contract, NYMEX light sweet crude, prices WTI for future delivery at Cushing, Oklahoma, while diesel itself trades off the New York Harbor ULSD futures contract. Terminal racks reprice off that diesel market every evening, and the weekly DOE number catches the result only at its Monday snapshot.
What is ULSD?
ULSD is ultra-low sulfur diesel: diesel with no more than 15 parts per million of sulfur, the only diesel sold for US highway use since EPA's 2006 to 2010 phase-in. It is the price benchmark because it is the fuel trucks burn, the grade behind EIA's pump and spot prices, and since May 2013 the grade the main US diesel futures contract delivers.
Diesel gel temperature: when does diesel gel?
Diesel gel temperature depends on the grade: ordinary No. 2 diesel starts forming wax at its cloud point, capped at 15.8°F in winter pipeline specs, and stops pouring near its pour point, capped at 0°F. No. 1 diesel clouds at -40°F or colder, which is why winter blends mix the two.