For the first time since mid-April, the national average price for a gallon of regular gasoline in the US dipped below $4. AAA data shows the price hit $3.999 on June 18, 2026, down from roughly $4.03 the day before.
The catalyst: a memorandum of understanding signed by President Donald Trump with Iran around June 17, aimed at ceasing hostilities for 60 days and reopening the Strait of Hormuz. That narrow waterway is one of the most important chokepoints for global oil transportation, and its closure has been squeezing supply since conflict erupted in late February.
What the deal actually does
The US-Iran MOU establishes a 60-day cessation of hostilities and commits both sides to reopening the Strait of Hormuz.
Oil markets reacted swiftly to the announcement. Both West Texas Intermediate and Brent crude benchmarks fell by more than 6% in the initial response.
