Three consecutive weeks of falling diesel prices had brought fuel’s national average down by 29 cents/gallon, but just one week later, those declines were given right back.
The U.S.’ national average for a gallon of on-highway diesel increased by 28.9 cents during the week ending May 4 to $5.64, just three-tenths of a cent lower than the 2026 high observed during the week ending April 6, based on U.S. Energy Information Administration data.
During the most recent week, the jump in the national average was caused in large part by a massive 61.1-cent surge in the Midwest, along with a 24.7-cent increase in the Rocky Mountain region.
[Related: 80 ways to maximize your truck's fuel efficiency]
With price increases seen across the U.S., California continues to hold the most expensive fuel at $7.36/gal., followed by the West Coast less California at $6.00/gal.
The cheapest fuel is in the Gulf Coast region at $5.18/gal., followed by the Lower Atlantic at $5.33/gal.
Prices in other regions, according to EIA:
- New England -- $5.86
- Central Atlantic -- $5.87
- Midwest -- $5.74
- Rocky Mountain -- $5.52
ProMiles’ diesel averages during the same week climbed by 6.2 cents to $5.23/gal. nationwide. According to the ProMiles Fuel Surcharge Index, the most expensive diesel can be found in California at $6.30/gal., and the cheapest in the Rocky Mountain region at $4.96.
Download a compendium of 80 different ways to improve your diesel's MPG via this link.
Rates follow fuel up
Spot rates across the three primary equipment types -- dry van, reefer and flatbed -- all increased in tandem with diesel prices last week, according to the May 4 report from FTR Transportation Intelligence and Truckstop.com.
Total broker-posted spot rates in the Truckstop.com system were once again at an all-time high during the week ending May 1. The total market broker-posted rate increased by 5.7 cents a mile to $3.32 after rising more than 3 cents in the prior week. All-in broker-posted rates were 32% higher than in the same week last year while rates excluding a calculated surcharge were nearly 26% higher.
Refrigerated spot rates rose for the first time in four weeks, though this week of the year often sees a turn with the Mother’s Day holiday upcoming. Dry van rates also usually rise during comparable weeks after mostly declining in April. Flatbed spot rates rose for an 18th straight week -- the 23rd time in the past 24 weeks.
Dry van spot rates inched up 3.8 cents to $2.56/mile, as shown in the chart, to a level 38% higher than in the same week last year -- up 31% excluding a surcharge. Flatbed rates continued the surge ongoing since the Fall.
[Related: Flatbed freight's remarkable rise -- total rates up, fuel dips again]
The DAT Freight & Analytics network observed similar trends during the most recent week with spot rates rising in all three equipment types, though with more modest gains than FTR and Truckstop.com observed.
Dry van rates on DAT load boards increased by a penny to $2.37/mile. Reefer rates up 1 cent to $2.72/mile. Flatbed rates saw a 3-cent increase to $3.05/mile.
The Commercial Vehicle Safety Alliance's International Roadcheck looms large next week, May 12-14, almost always bringing an increase in spot rates. Equipment posts typically fall significantly as carriers look to reduce exposure to inspections, DAT's Dean Croke said, especially in reefer and flatbed segments.
"Reefer carriers tend to take time off at twice the rate of others, and this year’s overlap with Mother’s Day weekend will further compress capacity for perishable freight," Croke noted. "Meanwhile, flatbed operators will face intense scrutiny regarding load securement, a focus area for inspectors this year."
Croke added that with the start of Vidalia onion season in the Southeast, reefer carriers running out of that region are in a favorable position.
"If you’re running Southeast-to-Northeast corridors, you have real pricing power right now," he said. "Mother’s Day floral volumes are adding pressure for shippers and brokers on top of the ongoing enforcement hangover from [Florida's] Operation Highway Shield," -- a four-day enforcement effort in the Sunshine State in late March targeting "commercial vehicle safety violations, criminal activity, and threats to Florida’s transportation network," state officials said. The effort resulted in more than 3,300 inspections with 176 drivers taken out of service.
