Why diesel costs more than gasoline

Diesel costs more than gasoline at the pump for four structural reasons: taxes, refining, competition for the same barrel and exports. For the week of Nov 2, 2026 the US average diesel price was $6.292 a gallon and regular gasoline $4.153, so diesel cost $2.14 a gallon more. Diesel has cost more than regular gasoline in every weekly survey since the week of Aug 31, 2015, 584 weeks in a row; the last week gasoline cost as much or more was Aug 24, 2015. None of the four reasons is a seasonal fluke. They are built into how diesel is taxed, made and used, which is why the diesel premium tends to persist rather than come and go.

Taxes

Start with the part set in law. The federal excise tax on diesel is 24.4 cents a gallon, a 24.3-cent excise plus a tenth-of-a-cent leaking-tank fee, against 18.4 cents on gasoline. That is a 6-cent gap Congress set in 1993 and has not changed since. Most states also tax diesel at a higher rate than gasoline. Every cent of it rides inside the DOE number, before a drop of fuel is even refined.

Refining

Diesel is a middle distillate, and turning crude into on-highway ULSD takes deeper processing than making gasoline, because the sulfur has to come down to 15 parts per million. A barrel of crude also yields more gasoline than distillate when it is refined, so diesel draws on a smaller slice of each barrel. Tighter spec and thinner yield both push the cost up.

Competing demand for the same barrel

Here is the one most drivers miss. Heating oil and diesel are practically the same fuel, per EIA, so every winter the furnaces of the Northeast compete with trucks and farms for the same middle-distillate barrel. Jet fuel and marine fuel pull from the same pool. When distillate demand runs hard, diesel can climb even in a stretch when gasoline is flat, because the barrel is being pulled in more directions than gasoline is.

Exports

The US ships a large volume of distillate abroad, which keeps a floor under the domestic diesel price even when US demand softens. Gasoline is far more of a domestic-only fuel, so it does not carry the same export pull.

The shared floor underneath both

It helps to remember what diesel and gasoline have in common. Both are refined from the same crude oil, and crude is the single biggest piece of either pump price. EIA puts crude at about 51 percent of the retail on-highway diesel price averaged from 2004 through 2025. So the two fuels rise and fall together on the crude that makes them, and the four reasons above are why diesel carries a premium on top of that shared base rather than why it moves day to day. When people ask why diesel is expensive, the short answer is that crude sets the floor and taxes, refining, distillate demand and exports build the diesel premium on top.

Worked example: the wedge you can see

The tax gap alone is 6 cents a gallon, diesel over gasoline, fixed and verifiable. On top of that, the retail-minus-spot gap, $1.895/gal for the US average in the week of Nov 2, 2026 and tabled on the diesel spot price page, is where all the taxes and the distribution cost sit between the wholesale hub and the pump. Diesel carries a heavier version of that wedge than gasoline does, and the refining and demand story stacks on top. Add it up and the pump premium follows.

Is diesel always more expensive than gas?

Not always, though it has been for years. Across all 1,703 paired weeks since Mar 21, 1994, diesel cost more in 81.0% of them. From 1994 through 2004, gasoline cost more than diesel in 270 of 563 weeks. EIA dates the turn to September 2004. Before then diesel was often the cheaper fuel, rising above gasoline mainly in winters when heating-oil demand ran high; since then, EIA says, growing worldwide demand for diesel and other distillates and the move to ultra-low sulfur diesel have kept it generally higher the year round. The widest gap on record is $2.14, for the week of Nov 2, 2026. The diesel price history chart tables both fuels by year.

Monday Diesel reports the diesel number and the retail layer that sits inside it. It explains why the premium exists and it does not forecast where the diesel-to-gasoline gap goes next.

Monday Diesel is a free weekly read of the DOE diesel number and what it does per mile. Built entirely from EIA's public data, in your inbox before dispatch, one email a week.