Benchmark price is up, futures down, diesel on its own

John Kingston

Tue, July 28, 2026 at 9:08 AM PDT 4 min read

Oil prices are plummeting again, but the benchmark used for most fuel surcharges has risen for a third consecutive week.

The Department of Energy/Energy Information Administration average weekly retail diesel price climbed 17.9 cents/gallon to $5.313/g, effective Monday but published Tuesday. It's the third consecutive week of an increase, tacking on 73.5 cts/g during that time.

But as a reflection of how volatile markets have been, the latest DOE/EIA price, even after such a steep slide, has risen to a level that is the highest since just June 8, when it was $5.21/g. It is just under where it was on April 27–$5.351/g–but since that day has experienced double digit increases or decreases eight out of the last 13 weeks.

Given the lag in retail changes, the price would not have been expected this week to reflect the sharp fall in futures prices that began when trading opened for the week Sunday evening U.S. time. That decline followed lower prices Friday that were seen not as a reversal of the market but more of a "breather" after several days of sharp increases.

Possible peace?

The cessation over the weekend of what had been nightly U.S. attacks on Iran, and other rumblings of negotiations, led to higher futures market prices the first two days of this week. 

However, for diesel consumers, the more salient development is that once again, the price of that fuel did not match the fall in the price of crude. 

For example, on Monday the price of world crude benchmark Brent fell $8.42/barrel, settling at $88.36/b. It had settled above $100 just two days earlier. The decline marked a drop of 8.7%.

But also on Monday, the price of ultra low sulfur diesel (ULSD) on the CME commodity exchange declined 6.9 cts/g to settle at $4.1116/g. That was a slide of just 1.65%, far less than the plunge in Brent.

Spread like no other

It led to what appears to be a historic new number: if Brent was converted to cents per gallon and subtracted from the ULSD price, the number would exceed $2/gallon. There is no recent record of that ever occurring.

It is far from a perfect comparison, because front month Brent is for September barrels and front month ULSD is for August, so the crude can not turn into diesel to be delivered next month. But the relationship still shows how disconnected the two markets  have become. 

On the last trading day before the U.S. and Israel launched its attacks on Iran, that spread was about 87 cts/g.

At approximately 11:30 a.m. Tuesday, the spread had widened. Brent was down about 9.7% and ULSD was down about 0.2%.