Soybean oil hits 4-year high on biodiesel demand, raising the cost of the diesel carriers burn

Soybean oil is at a 4-year high, and biodiesel is the reason. Farm Progress reports the biodiesel boom is dragging its main feedstock up with it. For anyone running trucks or hauling fuel, this lands in the fuel bill. Soybean oil sets the floor under biodiesel, and biodiesel goes into the diesel pool that carriers buy every day.

The feedstock squeeze

Most U.S. biodiesel starts as soybean oil. When plants run hard, they bid more aggressively for oil, and the price climbs. A 4-year high means the raw material behind blended diesel costs more than it has since 2022.

Diesel at the rack is often a blend, anywhere from B5 to B20 depending on the market and the season. The biodiesel share of that gallon carries the feedstock cost, so when soybean oil moves up the blended gallon can move with it even when crude holds flat. A carrier watching only the WTI screen could miss where the next few cents are coming from.

What carriers pay

Fuel surcharges track diesel, usually on a lag of a week or two. When the pump number rises, the surcharge formula most shippers run rises behind it. A feedstock-driven bump in blended diesel could feed those tables the same way a crude move would, just from a direction shippers are not watching.

Carriers in states with biodiesel mandates feel it first. Their blend ratio is fixed by rule, so they cannot duck the pricier component by switching to straight petroleum diesel. They buy the blend the law specifies and eat whatever the soybean oil market does to it.

Fuel haulers see it from the other side of the hose. They move the product, and a wider gap between straight diesel and the blended gallon could change which loads pencil out and which terminals are worth the run.

What to watch

One question is whether soybean oil holds here or eases once the crush catches up to demand. Another is whether biodiesel margins stay fat enough to keep plants outbidding the food and export buyers for oil. Then watch the surcharge tables. Over the next couple of weeks they will either start reflecting the blend cost, or shippers will push back on paying more for a feedstock story that has nothing to do with crude. If the high holds into the back half of the year, the blended states could carry a cost the petroleum-diesel markets do not.