WEX, the Portland, Maine fleet and corporate payments company, launched the WEX Index on 10 November 2026, a report built on its own transaction data that found the average US fuel price paid by fleets rose about 43% in the third quarter, from $3.38 to $4.85 a gallon, while gallons pumped stayed essentially flat. Fintechbits’ archive shows WEX booked a $57.3 million revenue benefit from fuel prices in its third quarter, reported on 28 October 2026, so the fuel surge the WEX Index describes as a cost for fleets was also a revenue tailwind for WEX itself. The report covers January to September 2026.

What the WEX Index found

According to the WEX release, 38.1% of North American commercial fleets paid more than the local WEX Fuel Price Index benchmark for at least some fill-ups. Premium fuel made up 7.6% of transactions at an average premium of $0.78 a gallon, which WEX puts at up to $86.9 million of potential savings for vehicles that do not need it.

Among fleets with five or more drivers, 81.4% had at least one driver spending more on fuel than the fleet average. In an analysis of 8,798 vehicles, 27% were recommended for replacement with electric vehicles, saving a modelled average of $16,595, or 15%, over each vehicle’s service life.

The report also cites industry figures showing phishing attacks up 1,265% since the fourth quarter of 2022, when generative AI tools became widely available.

Melissa Smith, WEX’s chief executive and president, said: “Fleets can’t control the price of fuel, but they can control how they respond to it.”

How the fuel surge showed up at WEX

WEX earns part of its revenue as a percentage of fuel spend on its cards, so higher prices lift revenue even when volumes are flat. In its third-quarter results, WEX reported revenue of $780.1 million, up 12.8%, including the $57.3 million fuel benefit, and raised full-year guidance on an assumed fourth-quarter retail fuel price of $4.81 a gallon.

That makes WEX an unusual author for a report about fleet costs. Its customers suffer when fuel rises, while its own revenue benefits. The report does not mention that link, which is understandable in a customer-facing document but worth bearing in mind when reading its savings estimates.

WEX’s fleet business is also the part of the company most exposed to that cycle. Its corporate payments and benefits segments are less tied to fuel, so a strong fleet quarter driven by prices can flatter group growth. Analysts usually strip out the fuel effect to see underlying volume and customer growth, and on WEX’s own data gallons were roughly flat.

Fintechbits analysis

Why the WEX Index Is Also a Sales Tool

The WEX Index is useful data and good marketing at the same time. The findings that stand out, overpaying against local benchmarks, unnecessary premium fuel and drivers spending above the fleet average, are all problems WEX’s controls and reporting are designed to fix. That does not make them wrong, but readers should treat the savings figures as WEX’s own estimates.

The flat-gallons finding is the most interesting point for payments investors. Fleets did not cut driving when fuel rose 43%. That means fuel card revenue tied to price is more sensitive to oil markets than to customer behaviour, which cuts both ways when prices fall.

The EV replacement figure is cautious and sensible: only 27% of vehicles analysed were recommended for replacement. Fintechbits has covered related spend controls in its piece on virtual cards and spend management.

Frequently asked questions

What is the WEX Index?

The WEX Index is a fleet and mobility spend report launched on 10 November 2026, built from WEX transaction data and covering January to September 2026.

How much did fleet fuel prices rise?

WEX data showed the average US fuel price rose about 43% in the third quarter of 2026 from a year earlier, from $3.38 to $4.85 a gallon, while gallons purchased stayed essentially flat.

Did higher fuel prices help WEX?

Yes. WEX reported a $57.3 million revenue benefit from fuel prices in its third-quarter 2026 results, within revenue of $780.1 million.

What to Watch Next

The next WEX Index edition and WEX’s fourth-quarter results will show whether fuel prices held near the $4.81 a gallon WEX assumed in guidance. A fall would ease fleet budgets and remove part of WEX’s revenue tailwind at the same time.