Diesel Hits a Record $6.43 a Gallon as the Strait of Hormuz Stays Shut

Diesel averaged $6.43 a gallon at U.S. pumps on September 18, 2026, the highest price on record and about 62 cents above the previous high of $5.81 set in June 2022 after Russia invaded Ukraine, according to data reported by ABC News. The price has climbed for weeks since the United States and Israel struck Iran in February, an attack that shut down most tanker traffic through the Strait of Hormuz, the waterway that once carried a fifth of the world's oil supply.

Regular gasoline reached $4.47 a gallon the same day, up $1.53 since the war began, according to GasBuddy data cited by ABC News. Iranian-backed Houthi forces have hit Saudi Arabian oil facilities, the U.S. military has struck five Iranian tankers, and Ukraine has intensified long-range strikes on Russian refineries, according to Fortune. Brent crude, the global benchmark, has held above $100 a barrel since September 9, when it jumped nearly 3 percent in a single session to $100.72. It traded around $103 on September 18.

Why the pain shows up on every shelf, not just at the pump

Since diesel moves the trucks that move nearly everything else, the increase does not stop at the pump. Wholesalers facing higher fuel bills tend to raise prices to retailers, who pass some of that along to shoppers. The effect shows up gradually, item by item, rather than all at once.

What forecasters actually disagree about

Forecasters do not agree on how far this goes. Bank of America's baseline still calls for Brent to average $83 a barrel in the second half of 2026, a price well below where it is trading now. But the bank's own research note lays out how shaky that baseline is: prices could hold between $95 and $120 if the attacks continue at the current pace, and spike as high as $150 if a strike takes out major oil infrastructure. Reaching a durable deal before the U.S. midterm elections is "increasingly unlikely," Bank of America analysts wrote in the note, cited by Fortune.

Households that heat with oil face the sharpest hit. The National Energy Assistance Directors Association projected in a report this month that heating oil bills will run more than 31 percent higher than last winter. Even homes that do not use oil heat should expect overall winter heating costs to rise more than 8.7 percent, the group said.

The Fed's narrow lane

The Federal Reserve raised interest rates on Wednesday for the first time since 2023, an attempt to keep the fuel spike from spreading into the broader economy rather than a fix for the spike itself. Annual inflation stood at 3.4 percent in August, more than a full point above the Fed's 2 percent target. Fed Chair Kevin Warsh, confirmed by the Senate 54-45 mostly along party lines in May and now replacing Jerome Powell, who had led the central bank since 2018, according to NPR, told reporters Wednesday that rate policy cannot touch the price of oil directly.

“We cannot affect any individual price, whether it be oil prices, whether it be food stuffs at the grocery store. But what we can do, and will do, is ensure that any change in relative prices don't broaden out.”

That distinction matters for anyone expecting the Fed to bring diesel prices down. It will not, and Warsh did not claim otherwise. The tool he controls works on demand, not on tankers stuck outside the Strait of Hormuz. Whether diesel keeps climbing from here depends on a war the Fed has no vote in.