US Diesel Hits Record $5.85 a Gallon Amid Iran War

US diesel prices soared to an all-time record average of $5.85 a gallon on Friday as the six-month Iran war disrupts global fuel flows.

Diesel hit a new record price in the United States on Friday, soaring to an average of $5.85 a gallon for the first time ever, according to the Associated Press. The record comes as the six-month war between the US and Iran continues to disrupt the world's flow of fuel. Businesses across sectors are already seeing bigger bills, and some have passed costs to consumers through added fees on online orders and mailed packages. AP also reports the increases could carry political weight, with economic issues likely top of mind for voters in November's midterm elections.

Regular gasoline has also climbed, but not as fast as diesel: the average price was $4.15 a gallon, compared with $3.20 at this time last year, per AAA figures cited in the pack. Before the US and Israel launched their war against Iran in late February, the national diesel average was about $3.76, per AAA. Diesel has been more expensive than gasoline for decades and rises faster during energy crises because supply is more limited, demand is less flexible, and diesel sits at the center of global commerce. Households can drive less when gasoline is expensive, but there are few immediate substitutes for the networks that rely on diesel to produce and haul goods worldwide.

Brent crude, the international benchmark, was trading above $95 a barrel on Friday, up from roughly $70 before the war, with most tanker traffic bottlenecked in the Strait of Hormuz amid supply chain disruptions and Middle East production cuts. The prior peak came in June 2022, when diesel reached nearly $5.82 a gallon on average after Russia's invasion of Ukraine. Adjusted for inflation, prices have been higher before: the AP notes diesel peaked at about $4.74 ahead of the 2008 financial crisis — equivalent to $7.20 in 2026 — and the 2022 record would be about $6.56 today. Gasoline's $4.15 average is still well below 2022's peak of nearly $5.02.

Diesel is integral to every part of the food supply chain, powering farm equipment and fishing boats as well as the trains, cargo ships and trucks that stock grocery stores. The Independent Grocers Alliance, a group of 7,500 global supermarkets, says fuel accounts for roughly 15% to 30% of the total cost of food. Michigan State University food economics professor David Ortega says refrigerated items are often first to see prices rise; in July, overall US grocery prices were up 2.7% year over year, while seafood rose 7% and fresh fruit 4.9%. He cautioned other factors can play a role — lettuce prices actually fell despite higher transport costs due to a demand drop from the cyclospora outbreak. "Early on, much of the cost increase gets absorbed along the supply chain through existing freight contracts and retailer margins," Ortega said, but as contracts reprice and fuel surcharges take hold, more of that cost reaches the grocery store.

The shock is already showing up in shipping fees. In April, Amazon rolled out a temporary 3.5% fuel and logistics surcharge on some third-party sellers, and UPS, FedEx and the US Postal Service added fees on some packages earlier in the war, citing rising fuel-related operational costs. Ajesh Kapoor, CEO of trucking technology company SemiCab, said trucking can adapt to rising diesel prices but only to a point: "Diesel price has a very, very direct impact on everything that moves on pretty much any mode." The ramifications extend beyond consumer goods — some public transit buses and trains run on diesel, and diesel generators are often used for backup or emergency power, if not central electricity sources in remote regions.

Experts warn consequences could deepen the longer the war grinds on, particularly for countries in Africa and Asia that rely heavily on Middle East imports and have already been hit hardest by energy shocks over the course of the war. Neil Atkinson, energy analyst and senior fellow at the National Center for Energy Analytics, said refined products like diesel are becoming more expensive as supplies stretch: "This is gradually becoming a major crisis because A) the prices themselves are very high — but the physical stocks of these products are dwindling," he said in a weekly briefing with maritime data firm Lloyd's List Intelligence, pointing to strain on the global refining system.