Diesel Prices Jump 36.8 Cents as Oil Markets Tighten

U.S. on-highway diesel prices climbed sharply during the latest reporting week, adding another significant fuel expense for truck drivers and motor carriers.

The national average reached $5.967 per gallon for the week ending September 7, according to new data from the U.S. Energy Information Administration. That was an increase of 36.8 cents per gallon from $5.599 the previous week.

Diesel Prices are now $2.201 per gallon higher than one year ago and $2.412 higher than two years ago.

The increase was widespread. Every major U.S. region tracked by EIA reported higher diesel prices for the week.

Diesel Prices Rise Across Every Region

The West Coast recorded the largest regional increase, with diesel jumping 49 cents to $6.987 per gallon.

California remained the most expensive area tracked by EIA. The statewide average climbed 54.6 cents in one week to $7.764 per gallon.

The Gulf Coast remained the least expensive major region, but prices there still increased sharply. The average rose 39.4 cents to $5.754.

Here are the latest regional averages:

• U.S.: $5.967, up 36.8 cents
• East Coast: $5.744, up 29.6 cents
• Midwest: $5.946, up 37.5 cents
• Gulf Coast: $5.754, up 39.4 cents
• Rocky Mountain: $5.805, up 25 cents
• West Coast: $6.987, up 49 cents
• California: $7.764, up 54.6 cents

The Central Atlantic also moved above $6, reaching $6.051 per gallon. New England reached $5.990.

Diesel Prices Are More Than $2 Above Last Year

The latest increase adds to a much larger year-over-year change.

National diesel prices are now $2.201 per gallon higher than during the comparable week last year, according to EIA.

The difference can become significant for trucks consuming large amounts of fuel.

For example, a truck purchasing 100 gallons at the current national average would cost about $220 more to fuel than at the national average one year ago, based on EIA’s price difference.

The year-over-year increase is even larger in some regions.

Gulf Coast diesel is $2.350 higher than last year. West Coast prices are $2.454 higher, while California’s average is $2.806 above its year-ago level.

Oil Markets Add Pressure to Fuel Prices

The diesel increase comes as global crude oil markets remain under pressure from disruptions in the Middle East.

Oil prices moved sharply higher again on September 10 as attacks on tankers increased concerns about available supplies and shipping routes. Brent crude climbed above $106 per barrel during Thursday trading, while West Texas Intermediate moved above $101.

The Strait of Hormuz remains an important part of the situation. The waterway is a major route for crude oil and petroleum products moving out of the Persian Gulf.

Reuters reported this week that Gulf oil exports remain well below their pre-conflict levels despite efforts to move additional barrels through the region. The disruptions have contributed to uncertainty over how much crude and refined fuel will reach international markets.

The current crude prices are also important because EIA’s newest forecast was completed using information available through September 3. That means the forecast does not specifically account for market events occurring after that date.

EIA Raises Its Diesel Price Forecast

EIA released its September Short-Term Energy Outlook on September 9 and increased its expectations for diesel prices.

The agency now forecasts the 2026 average retail diesel price at $5.07 per gallon. Last month, EIA expected an average of $4.85.

For 2027, EIA now forecasts diesel averaging $4.40 per gallon, up from its previous estimate of $4.07.

EIA also increased its forecast for the difference between crude oil and diesel prices, known as the diesel crack spread.

The agency now expects that spread to average $1.57 per gallon in 2026, compared with $1.30 in its previous forecast.

EIA expects Brent crude to average about $91 per barrel for all of 2026.

U.S. Diesel Inventories Expected to Remain Low

Crude oil is only part of the diesel price picture.

EIA is also pointing to tight supplies of distillate fuel oil, the petroleum category that includes diesel.

The agency forecasts U.S. distillate inventories will fall below 100 million barrels in September. EIA expects inventories to remain below the five-year low through the rest of 2026 and for much of 2027.

Several factors are contributing to that outlook.

According to EIA, global production of distillate fuel is expected to remain below last year’s levels in the coming months. Higher international prices have also encouraged U.S. distillate exports.

At the same time, seasonal conditions could add pressure. Refineries typically reduce distillate production during fall maintenance periods, while agricultural demand increases during the fall harvest.

EIA expects U.S. average diesel crack spreads to remain above $2 per gallon from August through November before gradually declining.

Global Diesel Supplies Remain Tight

Industry executives have also warned that the diesel market could remain tight through the winter.

Executives speaking at an energy conference this week pointed to reduced refining capacity and disruptions affecting Russia and the Middle East. Reuters reported that global diesel refining margins have risen sharply as available supplies have tightened.

That distinction matters because higher crude oil prices are not the only factor affecting what drivers pay for diesel.

Crude must first be processed into diesel at refineries. When supplies of finished diesel are limited, the price of diesel can rise faster than crude itself.

EIA’s September outlook reflects that situation. The agency raised its diesel crack-spread forecast by 20.8% for 2026 compared with its August forecast.

What EIA Expects Next for Diesel Prices

EIA expects some of the current pressure to ease eventually, but its forecast depends partly on improving oil movements from the Middle East.

The agency assumes tanker traffic through the Strait of Hormuz will gradually return toward normal levels. That would allow more distillate exports from Middle Eastern refineries and improve crude supplies available to refiners elsewhere.

However, EIA specifically notes that if Middle East oil flows remain constrained beyond the end of 2026, global distillate margins could be higher than its current forecast assumes.

For now, the latest weekly numbers show the immediate impact at U.S. pumps.

After briefly falling 5.3 cents during the previous reporting week, the national diesel average jumped 36.8 cents to $5.967.

EIA’s next weekly update is scheduled for September 15.