That record level, coming on top of months of soaring inflation, represents the latest bad news for President Joe Biden just five months before crucial midterm elections.
A year ago, the average price of gas in the US was just $3.07; since then it has shot up by 62 percent.
While Europeans have long been accustomed to paying much more at the pump, US gas taxes are lower — leaving car-loving Americans in shock over surging prices.
The increase in gas prices follows a steady rise in oil prices — which had plummeted in the early days of the Covid-19 pandemic as demand sagged, but have risen again as world economic activity resumes.
Oil prices soared further after Moscow invaded Ukraine in late February, and as international sanctions against Russia — a major petroleum producer — began to bite.
A barrel of crude currently sells for more than $120 in both London and New York.