Why the US Diesel Crack Spread Is Closing In on $100 — and Why Analysts Say It Won't End Soon

The U.S. diesel crack spread has blown past $97 per barrel and is closing in on $100 because a dense web of concurrent supply-side shocks — a closed Strait of Hormuz, destroyed and stranded refinery capacity across the Middle East, Russia, and China, the collapse of Persian Gulf diesel exports, a record IEA supply deficit revision, and the resulting overload on U.S. refiners — has crushed global diesel supply far more than crude supply, creating an extreme product-specific shortage that analysts across Goldman Sachs, Citi, Bank of America, and Jefferies see persisting for months .

What's pushing the diesel crack spread to $100

The front-month NY Harbor ULSD (diesel) crack spread — the difference between diesel futures and WTI crude — reached $93.84/bbl on August 10, 2026, a record . By August 13, Jefferies noted it had exceeded $97 and was "closing in on $100," equaling the peaks seen in March 2026 at the height of the initial Iran conflict . The broader 3:2:1 crack spread (gasoline + diesel vs. crude) hit a record $69.66/bbl in mid-July .

The converging supply-shock drivers

Strait of Hormuz effectively closed. Ship traffic through the strait is at a near-standstill except for a handful of vessels paying passage fees; insurance is unavailable or prohibitively expensive, and seafarers refuse to transit . Pre-war flow was ~140 ships/day; Bank of America's commodity team says only 5–10 ships per day are currently moving through . This has removed the single largest conduit for Persian Gulf crude and refined products from global markets.

Persian Gulf diesel exports have collapsed. Major refineries in Saudi Arabia, Bahrain, Kuwait, and the UAE remain either partially or entirely shut — damaged by strikes, logistically stranded by the Hormuz closure, or operationally unable to restart . The Iran-Ukraine wars have knocked out roughly 9% of global refining capacity — 20 Middle Eastern refineries have been struck or rendered inoperative.

Russian refining hammered. Ukrainian drone attacks have repeatedly struck Russian refineries. Russia itself banned diesel exports as a result, removing a major global supplier from the export market . Bloomberg describes a "wave of Ukrainian attacks on Russian plants" that has "severely constrained" output .

China not filling the gap. Chinese refinery runs are lower, and Beijing has restricted fuel exports, removing what might otherwise be a swing supplier able to relieve tightness .

IEA slashed its supply outlook. On August 12, the IEA said global oil supply had fallen "well below demand" and cut its 2026 supply forecast sharply, citing the Hormuz shutdown, the U.S. blockade on Iranian exports, Bab el-Mandeb attacks, and reduced Kazakh CPC Blend exports . The agency noted global oil supply was running 6.3 million bpd below year-ago levels. Global oil buffers are now "dangerously low," per the IMF .

U.S. refiners running flat out, but can't fill the gap. U.S. refiners are operating at high utilization and seeing record profits, but U.S. diesel inventories sit near multi-year lows and retail diesel hit $5.35/gallon in early August — $1.55 above year-ago . The U.S. cannot compensate for the lost Persian Gulf, Russian, and Chinese barrel because those regions produced a structurally critical share of global diesel output, and U.S. refineries are configured differently and already at capacity .

Analyst outlooks

• Goldman Sachs (Samantha Dart): Expects refined fuel margins to stay 2–3× higher for the rest of 2026 than the 2013–2019 average, and warns that three simultaneous chokepoint crises could push Brent to $120/bbl by Q4 if Hormuz does not reopen . Goldman recommended a long position in Dec 2026 European diesel vs. Mar 2027 to bet on winter tightness .

• Jefferies: Called the Hormuz shock "manifesting itself in cracks, not crude" — meaning the real pricing signal is in the diesel crack spread nearing $100, not in crude oil prices. It warned that unless the Strait reopens soon, the squeeze on refined products, especially diesel, will remain acute .

• Bank of America (Francisco Blanch): Warned the diesel market "appears poised to stay tight," noting that normalizing flows would require roughly 10× current Strait of Hormuz traffic. With only 5–10 ships/day vs. 140 pre-war, normalization is months away at best .

• Citi: Citi Research's head of energy strategy warned clients that diesel supplies remain tight and that inventory draws are accelerating .

The collective severity in one sentence

The world is living through a refining capacity crisis, not a crude supply crisis — the Strait of Hormuz closure, destroyed Persian Gulf refineries, Ukrainian attacks on Russian plants, Chinese export restraints, and the IEA's worst supply-deficit forecast in years have converged to create a diesel-specific shortage that U.S. refiners cannot fully offset, and every major bank sees this lasting at least through the end of 2026, with winter demand threatening to push conditions even worse.