2026 Has Been a Lesson in Fuel Volatility
If your fuel budget was built last fall, it did not survive this spring.
Weekly data from the Energy Information Administration shows the range. The U.S. average price for regular gasoline sat at $2.78 a gallon on January 12, 2026, then reached $4.50 on May 11, 2026.
That’s a swing of more than $1.72 per gallon inside five months. Diesel moved even harder, from $3.46 to $5.64 over a similar window.
The Week Everything Changed
Most of the move happened fast. Regular gasoline averaged $3.02 on March 2, 2026, then jumped to $3.50 the following week, a gain of nearly 49 cents in seven days. Diesel rose about 96 cents in that same week.
The cause was not a local pricing quirk. The EIA reported that crude oil and petroleum product prices rose sharply in the first quarter of 2026 following military action in the Middle East on February 28 and the subsequent de facto closure of the Strait of Hormuz. Brent crude went from $61 per barrel at the start of the year to $118 by the end of March, the largest quarterly increase on an inflation-adjusted basis in EIA data going back to 1988.
Where Prices Stand Now
Nothing has settled into a straight line since.
- Week of July 6, 2026: $3.78 for regular gasoline, a summer low
- Week of August 17, 2026: $4.05
- A year earlier, the week of August 18, 2025: $3.13
That’s about 92 cents more per gallon than the same week last year, an increase of roughly 30%.
Looking ahead, the EIA’s Short-Term Energy Outlook released August 11, 2026 forecasts regular gasoline averaging $4.01 in the third quarter of 2026, $3.72 in the fourth quarter, $3.78 for 2026 as a whole, and $3.29 in 2027. Diesel is forecast at $4.85 for 2026 and $4.07 in 2027. Forecasts move. Plan for the range, not the point.
Why Volatility Breaks Dollar-Based Fuel Management
Volatility does more than raise costs. It quietly disables the controls many fleets rely on.
- A $75 transaction limit bought about 27 gallons in January and about 17 gallons in May. Same rule, very different result.
- A driver with a 25-gallon tank could fill up under that limit in January and couldn’t in May, which means more stops and more transactions.
- Monthly dollar budgets look like overspending when prices rise, even if nobody drove an extra mile.
- Year-over-year comparisons stop meaning anything unless you separate price from volume.
How to Budget Through the Swings
The fleets that handled this year well did a few unglamorous things consistently.
- Budget in gallons first, then apply a price assumption. Gallons reflect your operation. Dollars reflect the market.
- Track cost per mile alongside price per gallon. It shows whether an increase came from the market or from your own operation.
- Set gallon-based transaction limits tied to tank size, so controls stay accurate whether gas is $2.80 or $4.50.
- Rebase your assumptions quarterly against published EIA averages instead of once a year.
- Report price variance separately from volume variance so leadership sees which costs you actually control.
The Bottom Line
You can’t forecast a global supply disruption. You can build a fuel program that doesn’t break when the market moves 49 cents in a week.
Price is the part you negotiate. Gallons are the part you manage.
Build a Fuel Program That Holds Up.
Get your customized Fuelz demo to see how gallon-based limits and on-demand reporting keep your controls accurate in any market.