US Diesel Hits Record $6.05 as Iran War Chokes Off Oil

Six dollars and five cents. That is what a gallon of diesel costs on average in America right now, and there has never been a number like it. ¹ The AAA reading reported on Sept. 13 tops the roughly $5.82 peak set in 2022 and stands $2.30 above the $3.75 price before the war with Iran began in late February. ¹ It is not a rounding error past the old high. It is a break into new territory that rewrites what it costs to move everything. ²⁷

Regular gasoline is surging alongside it, averaging $4.29 a gallon on the same day, up from $2.98 before the war. ¹ Gasoline remains below its June 2022 record of about $5.02, but that offers little comfort. ¹ A Brown University tracker estimates the surge has already added well over $700 a year to household fuel costs since late February. ¹ Americans are paying it at the pump, and then paying it again everywhere else.

What turns a pump shock into a broader economic shock is what diesel does. Nearly three-quarters of commercial shipping runs on diesel. ¹ Diesel is the workhorse behind the trucks that carry nearly everything Americans buy, plus rail, agriculture and construction. ¹ When diesel spikes, freight costs rise first, producer prices follow, and consumer prices surface at the grocery store and on store shelves with a lag. ¹² Analysts are flagging that pass-through as a fresh inflation risk exactly as the harvest and holiday shipping seasons arrive, when freight demand peaks. ¹

The pain extends well beyond trucking fleets into the freight, manufacturing, agriculture, retail and fulfillment networks that depend on diesel-powered transportation. ¹⁶ Fresh food, freight shipping, mass transit, construction and deliveries all cost more when diesel rises. ¹⁴ When gasoline spikes, drivers feel it instantly and cut back on weekend travel. ¹⁵ When diesel spikes, the impact on the entire economy can be much more significant, and could extend financial pain beyond the gas pump. ¹⁵

The supply disruption behind the prices is threefold, and each piece removes an alternative that once cushioned the market. ¹ First is the Strait of Hormuz, which normally carries about 20 million barrels a day — roughly a quarter of globally traded seaborne oil. ^{2 4} Iran has declared it closed, laid mines and attacked vessels, leaving traffic severely constrained. ¹ EIA data showed Q2 2026 flows collapsed to just 4.9 million barrels a day versus about 21 million pre-war, and some satellite trackers put ship arrivals at only about 4% of pre-war levels. ¹

Second, on the other side of the region, Houthi forces have seized the islands controlling Bab el-Mandeb — Mocha, Perim-Mayyun in the middle of the strait, Hanish and Zuqar. ¹ That gives them control of Yemen's Red Sea coast and a commanding position over the strait at the southern foot of the Suez route. ¹ They say navigation is safe except for Saudi vessels. ¹ Bab el-Mandeb normally handles about 4-6 million barrels a day of oil, a volume swollen in 2026 as Saudi crude was rerouted to the Red Sea. ¹

Third, after drone attacks launched from Iraq on Sept. 10-11 hit its pumping stations, Saudi Arabia shut its east-west pipeline, the main bypass that carried Gulf crude to Yanbu on the Red Sea. ¹ The line had capacity often cited at 5-7 million barrels a day, with recent throughput around 4-5 million barrels a day. ¹ With both straits constrained and the pipeline down, Gulf exporters have lost the bypass and the sea lanes at the same time. ¹

The numbers carry some fog, as wartime numbers do. While the widely cited Sept. 13 figures are $4.29 for gasoline and $6.05 for diesel, other readings for the same day show slightly higher — $4.31 and $6.20 for diesel, with AAA listing an all-time high of $6.2040. ¹ EIA's weekly survey for the week ending Sept. 7 showed regular at $4.16 and on-highway diesel at $5.97, with daily AAA readings moving higher since then. ^{29 31} And while most estimates put Hormuz's share at a quarter of seaborne trade, some analysis puts it at over a third. ¹⁰

What is unresolved is how long the pressure holds. Prices move daily, the straits remain contested in a war with no end in sight, and each ceasefire and each renewed strike swings the numbers. ¹ The exact path forward is tied to the conflict itself. ¹ For now, the record at the pump is the visible face of an inflation risk that Washington cannot control at the chokepoint and cannot shelter the household from. ¹