According to the most recent report by the U.S. Energy Information Administration (EIA), the national average cost of diesel fuel at the start of this week was lower than the previous week, and three of the five regions also reported small decreases.

The national average price per gallon of diesel fuel in the U.S. decreased by just under 1 cent as of July 28, 2025. However, the national average price of $3.80 per gallon is 3.7 cents higher than it was at the same time last year. 

This week, regional average prices decreased in three of the five regions. The decreases ranged from less than 1 cent in the East Coast and Midwest regions to just over 2 cents in the Gulf Coast region. Price increases were reported in the West Coast and Rocky Mountain regions.

The averages for several regions have reversed the trend of being lower when compared to the same period last year. Price averages are now higher in three regions than a year ago. The West Coast has the greatest difference at nearly 17 cents higher than this time last year. 

The most expensive place to buy diesel is Hawaii, at $5.24 per gallon, and the least costly is Texas, at $3.26 per gallon.

Regional Diesel Prices: Final Week of July

At the end of July, average diesel prices reported by region, as of July 28, were: 

• East Coast: $3.81

• Midwest: $3.79

• Gulf Coast: $3.45

• Rocky Mountain: $3.78

• West Coast: $4.54

Regional Diesel Prices: 4th Week of July

Average diesel prices reported by region, as of July 21, were: 

• East Coast: $3.82

• Midwest: $3.79

• Gulf Coast: $3.47

• Rocky Mountain: $3.77

• West Coast: $4.54

Regional Diesel Prices: 3rd Week of July

Average diesel prices reported by region, as of July 14, were: 

• East Coast: $3.79

• Midwest: $3.73

• Gulf Coast: $3.40

• Rocky Mountain: $3.71

• West Coast: $4.50

Regional Diesel Prices: 2nd Week of July

Average diesel prices reported by region, as of July 7, were: 

• East Coast: $3.76

• Midwest: $3.73

• Gulf Coast: $3.38

• Rocky Mountain: $3.66

• West Coast: $4.46

Regional Diesel Prices: 1st Week of July

At the end of June, average diesel prices reported by region, as of June 30, were: 

• East Coast: $3.77

• Midwest: $3.71

• Gulf Coast: $3.37

• Rocky Mountain: $3.66

• West Coast: $4.42

Regional Diesel Prices: 4th Week of June

In the fourth week of June, average diesel prices reported by region, as of June 23, were: 

• East Coast: $3.79

• Midwest: $3.78

• Gulf Coast: $3.43

• Rocky Mountain: $3.69

• West Coast: $4.46

Diesel Price Factors & Outlook

According to AAA, the late-June U.S. airstrikes in Iran caused petroleum futures to spike, with oil creeping up to $78/bbl. That quickly dissipated, and oil prices soon returned to pre-conflict levels. Because 61.6 million holiday travelers are expected to hit the road for the Fourth of July, gas prices may increase slightly during the first week of the month.