Fuel Prices Are Soaring, and Fleets Have No Choice but to Pay Up

North America’s commercial fleets are absorbing the largest oil supply shock on record, and they have nowhere to hide from it.

Since the Middle East conflict compromised the Strait of Hormuz in late February, triggering what the International Energy Agency has called the biggest supply disruption in the history of the oil market, fuel prices have skyrocketed. By the third quarter, average US fuel prices were approximately 43% higher year over year, according to data from WEX, a global leader in intelligent payment solutions.

WEX’s perspective on fuel prices comes from more than 40 years of helping businesses manage the cost of keeping their fleets moving. The newly released WEX Index, built from the company’s own mobility transaction data from January through September 2026, shows how those fill-up decisions played out in real time.

In most markets, a fuel shock would choke off demand. For commercial fleets, the working vehicles of everyday business, refueling is critical to staying operational. A delivery van must complete its stops, whether gasoline costs $3 or more than $4 a gallon, and a utility crew has to restore power in a storm.

Fleets have no choice but to keep filling up, whatever the cost.

“Fleets can’t choose to buy less fuel when prices surge, so the pressure lands on every decision around those transactions,” says WEX President and CEO Melissa Smith. “Our intention with the WEX Index is to provide guidance that helps businesses control fuel costs by looking at the details of each fill-up, including where, when and what their drivers buy.” 

New data from WEX shows fleets didn’t flinch, because they couldn’t. Drawing on transactions from more than 600,000 mobility customers, the WEX Index reveals that the number of gallons pumped remained essentially flat as fuel prices surged in 2026, averaging $4.85 a gallon in the third quarter.

Since then, the vise has only tightened. Prices for gasoline, used by the majority of commercial fleets, jumped 9.1% in September from August, according to the Bureau of Labor Statistics (BLS). Diesel, which powers much of the commercial fleet and moves the country’s freight, hit a record $6.53 a gallon in late September, according to AAA, nearly 77% above a year earlier. 

The shock is showing up in inflation data. Energy prices overall rose 20.4% in the year through September, according to the BLS, helping push US inflation to 3.7%. Higher transportation costs could also raise the price of goods on store shelves, including food.

For fleets, every stop at the pump still involves decisions: where the driver refuels and which nozzle comes off the hook. Those small, individual choices rarely draw much scrutiny, but with soaring costs, they add up fast.

The first choice comes before the vehicle even stops to fill up: where to pull in. According to the WEX Index, 38.1% of fleets paid above the local Fuel Price Index (FPI) this year. FPI is a daily benchmark for regular-grade fuel prices near a fueling location, based on WEX transaction data. 

Sometimes drivers are making the right call, since a cheaper station across town can turn into a more expensive fill once the extra miles and driver time are counted. In other instances, the driver stops at the usual place, or simply doesn’t know there’s a better price a block away. The real question is whether the price paid made sense for the particular vehicle and its route, particularly for companies with vehicles operating across the country. 

“As a national organization, our drivers fuel across a wide range of locations with thousands of vehicles traveling regularly across state lines,” says Neil Hartzell, vice president of logistics at TopBuild.

Then the driver reaches for a nozzle. Premium fuel isn’t inherently the wrong choice, and some vehicles call for it. But premium showed up in 7.6% of fleet transactions in the top five industries analyzed — such as retail trade, construction and manufacturing businesses — at about 78 cents a gallon more than regular, and some of it went into vehicles that don’t need it. Across those industries, WEX estimated the savings opportunity during the first three quarters of 2026 to be up to $86.9 million for vehicles that can switch from premium to regular grade. 

Enterprise Fleet Management advises clients to monitor this. “If a driver is fueling super unleaded for a half-ton cargo van, that driver could save on fuel costs without sacrificing efficiency by fueling regular unleaded instead. We want our clients to have these insights and be able to address them,” says Billy Dobosz, its assistant vice president of business development. 

The state-level data in the WEX Index sharpens that picture further. In Hawaii, drivers are paying 6 cents per gallon below the local price on average. Washington, DC, Iowa, California and Oklahoma tell a different story: Drivers in those places are paying 4 to 9 cents above the local price on average.

Fleet managers can’t control when a shipping lane reopens or the price of a gallon of fuel. What a fleet can control is where, when and how its drivers fill up. Each decision could save money for both fleets and their downstream customers. Data is how business owners, fleet managers and administrators find those savings and cut wasteful spending.

Fleets had no choice about whether to keep buying fuel. When the next shock hits, the choices they make about how they’re buying it can decide who ends up paying the most. 

Learn more about the data affecting the commercial fleet industry in the WEX Index: The Fleet and Mobility Spend Report.