The national average price for regular gas dropped again on Thursday, falling below the $4-per-gallon threshold to $3.999, according to AAA. It marked the fourth straight week that gas prices in the country have decreased. Fuel costs have dropped 52 cents per gallon over the last month. Thursday’s gas price decrease comes the day after the United States and Iran signed a memorandum of understanding to end their military conflict and reopen the Strait of Hormuz.

It is the first time the national average price for a gallon of regular gas has been below $4 since March 30. Gas prices began to drop across the country shortly after Memorial Day weekend, traditionally recognized as the start of the summer driving season, which usually correlates with higher prices at the pump. A few days earlier, gas prices reached $4.564 per gallon on May 21, a record high price for 2026, and the highest national average gas price in the U.S. since 2022. It was also the highest gas price since President Donald Trump took office in either term.