Why Is Diesel More Expensive Than Gas (and Why So High)?

Prices as of September 16, 2026 · Updated September 16, 2026

The short answer

Diesel always costs more than gasoline because of a higher federal tax, a costlier fuel to make, and stronger demand. It costs far more in 2026 because Russian diesel exports collapsed and U.S. refineries are already running flat out.

Diesel averages $6.31 a gallon as of September 16, 2026 against $4.37 for regular, a gap of $1.94 (AAA). In EIA's weekly survey diesel is 66.9% higher than the $3.77 of a year ago.

U.S. average, diesel
$6.31
66.9% higher than a year ago (EIA weekly)
Diesel minus regular
$1.94
44% above the price of regular
100 gallons for a truck
$631
$252 more than a year ago
EIA projection for 2027
$4.40
vs $5.07 projected for 2026

Diesel prices today (September 16, 2026)

The AAA national average for diesel is $6.31 per gallon, against $4.37 for regular, fetched this morning. A tractor-trailer taking on 100 gallons pays $631, about $252 more than the same fill a year ago. A 26-gallon pickup tank costs $164.06.

Week ofDiesel ($/gal)ChangeRegular ($/gal)Gap
September 14, 2026$6.29 +31.8¢ $4.32$1.97
September 7, 2026$5.97 +36.8¢ $4.16$1.81
August 31, 2026$5.60 −5.3¢ $4.07$1.53
August 24, 2026$5.65 +19.8¢ $4.08$1.57
August 17, 2026$5.45 +19.7¢ $4.05$1.40

Weekly rows: EIA weekly U.S. averages, No. 2 diesel and regular all formulations, surveyed each Monday. Today's figures: AAA national averages, fetched once each morning. The $1.97 gap in the week of September 14, 2026 is the widest in EIA's weekly series, which begins in 1994.

Diesel and gasoline at the pump since 2020

The two fuels come from the same barrel and usually move together. In 2022 and again in 2026 diesel pulled away, which is the signature of a distillate problem rather than a crude oil problem.

Weekly U.S. average retail diesel and regular gasoline prices since 2020, dollars per gallon $0.00 $2.00 $4.00 $6.00 2020 2021 2022 2023 2024 2025 2026 Diesel and gasoline at the pump Diesel 2026: $6.29/gal Regular gasoline 2026: $4.32/gal Diesel Regular gasoline
EIA weekly U.S. average retail prices, dollars per gallon, through September 14, 2026.

Why diesel costs more than gasoline every year

EIA's own answer gives three structural reasons, and diesel has cost more than regular gasoline in every full year of its weekly survey since 2005:

  1. Taxes. The federal excise tax on highway diesel is 24.4¢ a gallon, against 18.4¢ on gasoline. That 6-cent gap is there in every gallon before anything else happens.
  2. The fuel itself. Highway diesel has been ultra-low-sulfur since 2006. Removing the sulfur takes hydrogen and processing capacity that gasoline does not need, so a gallon of diesel costs more to make and to distribute.
  3. Demand. Diesel is the fuel of trucks, trains, ships, farms and mines, and the same distillate cut of the barrel is heating oil. EIA points to strong distillate demand in the United States, Europe, China and India, and a large share of what U.S. refineries make is exported (the weekly export figure is below).
Annual average gap between U.S. diesel and regular gasoline prices, 1994 to 2026, dollars per gallon $0.00 $0.30 $0.60 $0.90 $1.20 1996 2006 2016 2026 The two fuels cost about the same until the mid-2000s Diesel minus regular 2026: $1.14/gal
Annual average of the weekly gap between U.S. diesel and regular gasoline prices, EIA, 1994 to 2026 (2026 through September 14, 2026).
YearDieselRegularGap
2015 $2.71$2.43 $0.28
2016 $2.30$2.14 $0.16
2017 $2.65$2.41 $0.24
2018 $3.18$2.72 $0.46
2019 $3.06$2.60 $0.45
2020 $2.55$2.17 $0.38
2021 $3.29$3.01 $0.28
2022 $4.99$3.95 $1.04
2023 $4.21$3.52 $0.70
2024 $3.76$3.30 $0.46
2025 $3.66$3.10 $0.56
2026 (through September 14, 2026) $4.93$3.79 $1.14

Annual averages of EIA's weekly U.S. survey. The 2026 average gap of $1.14 is already wider than any full year in the series; the previous record was $1.04 in 2022. Diesel averaged less than regular in 1999 and 2001 to 2004.

Why diesel is so high in 2026

The structural gap is a few tens of cents. The 2026 gap is $1.94. The difference is a world short of distillate, and three things explain most of it.

1. Russia, which shipped 2.5 million tons of diesel a month a year ago, all but stopped

Russia has published no production data since 2022, so this section quotes what has been reported, dated and sourced. The pattern is consistent: Ukrainian drone strikes on refineries cut Russian distillate output through the spring and summer, Moscow restricted and then banned diesel exports to protect its domestic market, and the barrels Russia's customers used to buy had to come from somewhere else. The IEA's reading, in its October 2025 report, was that the drop in Russian middle-distillate exports "reverberated globally" as regular buyers bid up diesel and jet cracks to secure alternative supply.

2. Less crude through Hormuz, and the diesel-rich kind

The crude oil shock that lifted gasoline lifted diesel too, and by more. Trade-press analysis (FreightWaves, August 20, 2026) adds that the Middle East and Russian grades taken off the market are heavier crudes that yield more distillate than the light shale crude the U.S. produces, so the barrels lost were the diesel-rich ones. The gasoline explainer covers the crude side and the Hormuz numbers cover what the chokepoint decline does and does not measure.

3. U.S. refineries are already running flat out

When the world wants more diesel, the first place it looks is the U.S. Gulf Coast. EIA's weekly survey put refinery utilization at 96.8% of operable capacity for the week ending September 11, 2026. That is the 15th consecutive week at or above 95%, a run that began the week of June 5, 2026 and peaked at 98.0% in the week of August 28, 2026. It is the longest such run since 1998, when refiners held above 95% for 24 straight weeks. Utilization that high is the signal of a tight market: refiners run every unit they can when product margins reward each extra barrel, and there is no idle capacity left to bring on when demand rises.

Weekly U.S. refinery utilization since 2016, percent of operable capacity, with a 95% reference line 60% 70% 80% 90% 100% 2016 2018 2020 2022 2024 2026 Refineries have run near their ceiling all summer Percent of operable capacity Utilization 2026: 97% 95% line 2026: 95% Utilization 95% line
EIA weekly percent utilization of U.S. operable refinery capacity through September 11, 2026. Dashed line at 95%. The 2020 trough is the pandemic.
YearWeeks at 95% or aboveWeeks at 96% or above
1997 3027
1998 2824
2026 (through September 11, 2026) 1613
2018 2112
1994 2011
2004 159
2000 168
2005 86

The eight calendar years with the most weeks at 96% or above, EIA weekly series since 1990. Utilization is measured against operable capacity, which has shrunk as refineries closed; see the refining page for the count and capacity history.

What the market signals say

Diesel crack spread
$102/bbl
vs $46 for gasoline, week of September 4, 2026
Distillate inventories
107.9 mb
13% below the 2021–2025 same-week average
Distillate exports
1,674 kb/d
4-week average, 25% more than a year ago

The crack spread is a benchmark of what a barrel of product is worth over the crude that made it (not a profit figure). For the week of September 4, 2026 the New York Harbor diesel crack was $102.19 a barrel against $45.99 for gasoline, and $34.01 for diesel in the same week of 2025. The difference between the two cracks is worth about 134¢ a gallon at the pump, which is most of the gap between the two fuels. The diesel crack ranks 5th of 1,056 weeks since 2006; the record is $113.90 in the week of May 13, 2022.

U.S. distillate inventories stood at 107.9 million barrels in the week ending September 11, 2026, 13% below the 2021–2025 average for the same week and below the bottom of that five-year range (116.0 to 131.9 million). Exports of distillate averaged 1,674 thousand barrels a day over the past four weeks, against 1,340 in the same weeks a year earlier. Refineries running at capacity, inventories below the range, and exports up: that is a market drawing down what it has because it cannot make more.

Why your state is different

Crude and distillate trade on world markets, so the spread between states comes from state taxes and fees, low-carbon and low-sulfur fuel rules, and distance from a refinery. This week California averages $8.27 for diesel against $5.85 in Colorado, a gap of $2.41 a gallon.

See all 50 states ranked; every state page shows its diesel average next to regular. State averages are from AAA as of September 16, 2026.

Will diesel prices go down?

EIA projects they will. Its Short-Term Energy Outlook, as of September 16, 2026, has U.S. diesel averaging $5.07 a gallon in 2026 and $4.40 in 2027, with regular gasoline at $3.35, so EIA expects the gap to narrow but not to close. What would bring it down is the reverse of what pushed it up: Russian refineries back online, more crude through Hormuz, and refiners with room to spare after a full-throttle summer.

This is EIA's projection, not ours, and EIA reissues it every month; we pull the current edition from EIA's API on each weekly refresh.

Frequently asked questions

Why is diesel more expensive than gas?

Three structural reasons and one 2026 reason. Structurally, per EIA: distillate demand is strong at home and abroad, ultra-low-sulfur diesel costs more to make, and the federal excise tax on diesel is 24.4¢ a gallon against 18.4¢ on gasoline. In 2026 the gap widened far past those causes: the IEA reports that the drop in Russian middle-distillate exports sent regular buyers scrambling for alternative supply and bidding up diesel cracks, while U.S. refineries were already running near capacity. Diesel is $6.31 against $4.37 for regular as of September 16, 2026, a gap of $1.94.

Was diesel always more expensive than gasoline?

No. In EIA's weekly survey, diesel averaged less than regular gasoline in 5 of the years from 1994 to 2005; every full year from 2005 on has averaged higher. This year's average gap so far, $1.14, is wider than any full year in the series; the previous record was $1.04 in 2022.

Are U.S. refineries running at full capacity?

Close to it. EIA's weekly survey put utilization at 96.8% of operable capacity for the week ending September 11, 2026, the 15th consecutive week at or above 95%, the longest such run since 1998. Refiners run that hard when product margins reward every extra barrel, which is what the diesel crack spread is showing.

Will diesel prices go down?

EIA projects they will. Its Short-Term Energy Outlook as of September 16, 2026 has U.S. diesel averaging $5.07 a gallon in 2026 and $4.40 in 2027. That is EIA's projection, reissued monthly, not ours.

Which state has the most expensive diesel?

California, at $8.27 a gallon in AAA's survey, against $5.85 in Colorado, a spread of $2.41. Every state page on the gas prices hub shows its diesel average next to regular.

Related

Why are gas prices high?The same question for gasoline, with the crude oil side Gas and diesel prices by stateAll 50 states ranked, with the price decomposed What is a crack spread?The weekly gasoline, diesel and WTI calculation U.S. refiningEvery refinery, the capacity history, and what closed The Hormuz numbersWhat the chokepoint decline does and does not measure Strategic Petroleum ReserveThe crude stockpile and the 2026 drawdown Fuel prices by countryWhat Americans pay vs. the rest of the world Oil price shocks since 1973Every major crude price swing on one series

Sources: EIA Gasoline and Diesel Fuel Update (weekly retail prices), EIA Weekly Petroleum Status Report (refinery utilization, distillate stocks and exports), EIA spot prices (crack spread legs), EIA Short-Term Energy Outlook (projections), EIA FAQ (federal excise taxes and structural reasons), AAA (daily national and state averages), and the reported items linked in the Russia section. See methodology.