US gas prices fell to their lowest since February and could drop below $3 a gallon, GasBuddy said.
Three states — Oklahoma, Texas and Mississippi — now have average prices of $2.99 a gallon, De Haan said in a tweet.
Gas prices topped $5 a gallon in June, as global oil prices soared thanks Russia's war with Ukraine and an energy crisis in Europe.
On Monday, crude oil prices have came under downward pressure as traders worried about a fall in demand from China, the world's second-biggest economy, as public protests erupted over the country's strict zero-Covid policies.
Meanwhile, US demand for oil is under seasonal pressure, as cooler temperatures encourage Americans to stay at home, GasBuddy said.