The military conflict between the US, Israel, and Iran that began on February 28, 2026, has sharply increased fuel costs in the United States. Gasoline rose more than 50% from its pre-war average of about $2.98 per gallon, while diesel climbed more than 60% year-over-year to nearly $6.27 per gallon. Brown University estimates that US consumers spent more than $100 billion extra on gasoline and diesel from the outbreak of hostilities through September 2026, or about $780 per household. Disrupted shipments through the Strait of Hormuz, a major oil-transit chokepoint, removed an estimated 11 million to 14 million barrels per day from global markets at the peak. Refiners also prioritized diesel and jet fuel over gasoline, tightening gasoline supplies. A June interim ceasefire briefly stabilized prices, but renewed tensions and strikes pushed September gasoline prices to $4.15-$4.50 per gallon and diesel to at least $5.90. Analysts say pre-war prices may not return until 2027, and even a full cessation of hostilities could take six to 12 months to lower prices meaningfully while inventories are rebuilt.