Why does diesel cost more than gasoline?
Diesel now runs about a dollar a gallon above regular gas — but it was the cheaper fuel until the mid-2000s. Here's what our data shows about the flip, and the well-documented reasons behind the premium.
Diesel runs about 100.7¢ above regular
This part isn’t in dispute — it’s EIA retail price data we hold directly. As of the week of June 15, 2026, diesel averaged $5.06 a gallon against $4.05 for regular gasoline — a gap of about 100.7¢, or roughly 25%.
But diesel hasn’t always been pricier. Our EIA series begins in 2000, and in those early years the two fuels traded places: diesel’s annual average sat below regular gasoline in 2001–2004. Diesel crossed into a persistent premium in 2005 and has stayed above regular every year since — widening to as much as 160.7¢ a gallon in 2022.
Source: U.S. Energy Information Administration, weekly U.S. average retail price — No. 2 diesel and regular (all-formulations) gasoline. Our diesel series begins in 2000 (EIA’s weekly retail diesel data does not go back further), so the chart starts there.
Why diesel carries a premium
The EIA addresses this question directly. It says diesel has been priced above regular gasoline “almost continuously since September 2004,” and gives three main reasons: relatively high demand for diesel and other distillate fuels, the higher cost of producing lower-sulfur diesel, and a higher federal excise tax. [1] Here is each, with the supporting detail.
A cleaner, costlier fuel to refine. Since 2006, EPA rules have required on-highway diesel to be ultra-low-sulfur (no more than 15 parts per million of sulfur, phased in by 2010), down from a 500 ppm standard set in 1993 and roughly 3,000 ppm before that. [2] Stripping sulfur out takes extra refinery processing — “catalytic hydrotreating” — and the EIA says that transition to lower-sulfur diesel “affected diesel fuel production and distribution costs.” [1] (The EIA doesn’t publish a specific per-gallon figure for that cost, so we don’t put a number on it.)
Higher taxes. The federal excise tax on on-highway diesel is 24.4¢ a gallon — 6¢ higher than the 18.4¢ on gasoline. [3] Those federal rates have been fixed since 1993. [7] State taxes tilt the same way: as of July 2024 the average state tax was 34.8¢ a gallon on diesel versus 32.6¢ on gasoline. [3]
It competes with winter heating oil. Diesel and heating oil are both “middle distillates” made from the same part of the barrel. The EIA notes that “during the fall and winter, the demand for heating oil affects diesel fuel prices” — the two compete for the same supply, which can push diesel up in colder months. [4] Historically that was the main time diesel ever cost more than gas; today the premium is year-round.
Strong, global demand. Diesel/distillate demand has been high “especially in Europe, China, India, and the United States,” [1] and the EIA notes “international demand for distillate fuel affects U.S. diesel fuel prices.” [4] In 2022 it flagged that U.S. distillate demand had been high since early 2021 on increased trucking and rail freight. [6]
Tight supply widens the gap. Distillate inventories are thin and sensitive to refining hiccups. The EIA reported that by October 2022 the U.S. had 25 days of distillate supply — the fewest since 2008 — and pointed to reduced U.S. and global refining capacity since 2020 as a main reason. [5] That episode drove the widest diesel-over-gasoline gap in our record.
It hits truckers, fleets, and diesel drivers hardest
A diesel premium isn’t just a line item for diesel drivers. Diesel moves most U.S. freight — long-haul trucks, trains, ships, and farm and construction equipment — so when diesel runs 25% above gasoline, that cost flows into shipping, delivery, and ultimately the price of goods. For a household with a gasoline car the gap is mostly academic; for a trucker, fleet operator, or farmer it’s a direct hit. The structural pieces — the cleaner-fuel standard and the tax gap — aren’t going away, so diesel is likely to keep its premium; how wide it gets swings with demand, the season, and how tight distillate supply is.
Diesel vs. gas, answered
- Why does diesel cost more than gasoline?
- According to the U.S. Energy Information Administration, diesel has cost more than regular gasoline almost continuously since 2004 for three main reasons: relatively high demand for diesel and other distillate fuels (in the U.S. and abroad), the higher cost of producing today's cleaner, lower-sulfur diesel, and a higher federal excise tax on diesel (24.4 cents per gallon versus 18.4 cents on gasoline). Seasonal heating-oil demand and tight distillate supply can widen the gap further.
- How much more does diesel cost than gas right now?
- As of the week of June 15, 2026, the U.S. average for diesel was $5.06 per gallon versus $4.05 for regular gasoline — about 100.7¢ more, or roughly 25%, per EIA data.
- Has diesel always been more expensive than gas?
- No. In our EIA data, which begins in 2000, diesel's annual average was actually below regular gasoline in 2001–2004. Diesel moved to a persistent premium starting in 2005 and has stayed above regular every year since.
- Why are higher diesel prices a big deal?
- Diesel powers most of the trucks, trains, and equipment that move freight and goods, so a higher diesel price feeds into shipping and delivery costs. It matters most for truckers, fleet operators, farmers, and anyone driving a diesel vehicle.
Where the causal claims come from
- [1]U.S. EIA, Frequently Asked Questions — “Why are diesel fuel prices higher than gasoline prices?”
- [2]U.S. EIA, Today in Energy — “Large reduction in distillate fuel sulfur content has only minor effect on energy content” (Feb 24, 2015)
- [3]U.S. EIA, FAQ — “How much tax do we pay on a gallon of gasoline and on a gallon of diesel fuel?” (rates as of Jul 1, 2024)
- [4]U.S. EIA, Diesel fuel explained — “Factors affecting diesel prices”
- [5]U.S. EIA, Today in Energy — “Strong demand for diesel leads to high prices and tight inventories going into winter” (Nov 10, 2022)
- [6]U.S. EIA, Today in Energy — “Increased demand and low inventories drive U.S. distillate prices higher” (Mar 10, 2022)
- [7]U.S. Congressional Budget Office — “Increase Excise Taxes on Motor Fuels…” (federal 18.4¢ gasoline / 24.4¢ diesel, fixed since 1993)
Price data throughout is from the U.S. Energy Information Administration and held in our own database. Figures are nominal (not inflation-adjusted); our weekly diesel and gasoline series both begin in 2000.