On September 21, 2026, the average price of diesel fuel for use in highway vehicles reached $6.529 per gallon, according to the U.S. Energy Information Administration. In 2024, trucks and trains transported between two-thirds and three-quarters of all domestic freight (about 13 million of 17.7 million total tons transported), almost all using diesel-fueled engines. Shippers of perishable goods, which cannot be easily stored for later shipment, may be especially sensitive to high fuel costs. The Trump Administration and some Members of Congress are reportedly considering restrictions on the export of diesel fuel, with the goals of increasing domestic supply and reducing consumer product prices through lower shipping costs. One such bill (H.R. 10423) would immediately ban exports of diesel fuel until the end of the calendar year. Another (H.R. 10422) would automatically implement an export ban if the diesel fuel price averages more than $5.00 per gallon over a two-week period; the export ban would remain until the diesel fuel price was below $4.50 per gallon for 30 consecutive days. The United States is a major exporter of diesel fuel. If diesel fuel exports are restricted, refineries could be left with a temporary surplus, potentially leading to lower prices in the short term in some areas. Fluctuations in the price of diesel fuel could present various surface, maritime, and aviation transportation policy issues for Congress to consider.
In response to a proposed export ban, industry analysts reportedly forecast that refineries could respond by reducing production of diesel until surpluses are depleted, depending on how any restrictions would be structured. Diesel fuel is produced by refining crude oil in a process that also produces gasoline, aviation fuel, and other products. A decline in the production of diesel could be accompanied by declines in the other types of fuel produced, potentially raising those prices depending on the overall supply and other factors. In the global market, countries accustomed to importing diesel fuel from the United States would need to find other exporters at potentially higher prices. For example, Mexico reportedly imports roughly 60% of its diesel from the United States. U.S. consumers may see higher prices for imported goods if diesel fuel costs rise in those countries.
Railroads and trucking companies may respond to high diesel prices by internalizing additional costs and reducing profitability or by adding fuel surcharges to their base shipping rates. Base rates are calculated assuming a certain price for diesel fuel, and surcharges (sometimes per mile, sometimes as a percentage of the base price) are calculated on the basis of how much the current price of diesel fuel exceeds the assumed price. As of September 2026, fuel surcharges at some logistics companies are more than 25%.
Elevated diesel fuel prices could be contributing to a reported shift of freight traffic from truck to rail or intermodal (truck-and-rail) freight. The transportation of cargo partly or entirely by train instead of by truck may allow shippers to reduce certain costs because of rail's comparative fuel efficiency, though transport by trucks alone may reduce travel times. Rail's ability to carry additional cargo depends on the availability of railcars and locomotives and the capacity available at intermodal facilities where cargo can be loaded and unloaded. Lower diesel fuel prices may reduce fuel surcharges, thereby reducing motivations to shift cargo movements from trucks to rail.
If elevated motor fuel prices were to cause a decline in consumption, such a decline could reduce the amount of fuel taxes collected by the federal government and deposited into the Highway Trust Fund, an important source of funding for many highway and public transportation projects. Congress often considers fuel tax revenue and spending when it reauthorizes surface transportation programs (currently scheduled to expire on December 11, 2026) and could do so in upcoming surface transportation bills or through stand-alone legislation.
Fuel costs can also be an issue for maritime carriers. Some barge tows are powered by diesel engines. Barges can be critical for agricultural shippers during the harvest season and can also transport fuels along river systems and coastal markets.
A diesel export ban may amplify calls by some to waive the Jones Act, which refers to provisions of law that require all waterborne shipments between U.S. ports to be transported on vessels that are U.S.-built and U.S.-crewed. By permitting port-to-port shipments of diesel fuel on foreign vessels, surpluses of diesel fuel might be more economically distributed to other markets in the United States not connected by pipelines that could help transport surplus diesel fuel if sufficient ships or barges were not available.
The Department of Homeland Security (DHS) issued a Jones Act waiver on March 17, 2026, shortly after military operations began against Iran. DHS extended it twice, through mid-November 2026. Of the more than 200 voyages taken under the March 17 Jones Act waiver as extended, over 20 carried diesel fuel according to reports published by the U.S. Maritime Administration as of September 2026.
If refiners respond to a diesel export ban by reducing refinery output, the supply of kerosene-derived aviation fuel might lessen, increasing costs for airlines. U.S. airlines previously had pursued financial strategies to hedge against volatility in the price of aviation fuel. U.S. airlines reportedly have largely retreated from the practice in recent years, while European airlines have continued to hedge. In response to higher fuel prices, airlines may raise passenger fares or freight rates, reduce capacity (i.e., offer fewer flights), reduce profitability, or some combination of these. Congress could monitor fares and rates in the context of consumer choice and the national economy when considering how a diesel export ban might change aviation fuel prices. Refiners may be able to shift production to increase the percentage of kerosene produced from each barrel of oil, which could offset lower production due to reduced oil processing.