The GasBuddy national average gas price increased 6.5 cents to $3.09 which is 4.5 cents higher than a month ago and 1.8 cents higher than a year ago. The median U.S. gas price is $2.99 per gallon, up 5 cents from last week and about 10 cents lower than the national average. The national average price of diesel has increased 8.1 cents in the last week and stands at $3.606.