Diesel Prices Reach New High Over Labor Day Weekend

Diesel prices in the U.S. broke a new record high this past weekend, as the U.S. and Israel’s continued war on Iran has led to a rapid increase in worldwide fossil fuel costs over the past six months.

On Friday, a gallon of diesel gas surpassed $5.85, the highest price ever recorded. The increased fuel costs will likely translate into higher prices for consumer goods, since many of the products Americans purchase are transported across the country using diesel-fueled shipping trucks.

Having already passed the record, diesel costs continued to climb through the weekend, reaching above $5.90/gallon on Labor Day.

Prices for regular grade gasoline, too, are climbing. After a brief mid-summer respite due to the signing of the Memorandum of Understanding between the U.S. and Iran, prices increased again after that deal fizzled out. As of Monday, gasoline cost $4.15/gallon across the U.S., on average.

These prices are significantly higher than where they stood at the beginning of the year, when diesel cost $3.52/gallon, on average, and regular grade gasoline was $2.796/gallon. Put differently, since early January, gasoline prices across the U.S. have increased by 48.4 percent, while diesel has gone up by 67.6 percent.

Despite these troubling trends, Trump claimed in a Truth Social post this weekend that oil prices “will drop precipitously, like everything else is dropping (but more!), when we WIN the war with Iran.” He also renewed his promise of “two dollars a gallon” for regular gasoline, a pledge he made in the 2024 presidential campaign, asserting that it would “all happen quickly.”

Notably, Trump has been making promises like these for the past six months of the war. In early March, for example, when fuel prices were initially rising, Trump called the price increases a “short-term” problem that was “a very small price to pay for USA, and World, Safety and Peace.” He also stated that prices would “rapidly drop” when the war ended, claiming at the time that the war would only last a few more weeks.

Even if the war on Iran ends relatively soon, fuel prices are unlikely to recover quickly, assessments from within his own administration have admitted.

A report from the Energy Information Administration (EIA) predicted in April that regular grade gas prices will likely remain around $3.70/gallon, on average, for the remainder of 2026. Furthermore, the EIA said that gas prices will be around $3.46/gallon, on average, for all of 2027. Both numbers are well above where prices stood at the start of the war.

Importantly, those predictions were made based on an optimistic view of the U.S.’s war on Iran, with the EIA basing their numbers on the idea that the conflict would “not persist past April.” As the war has lasted several months beyond that point, gas prices will likely be above those predicted averages.