With an average increase of 3.8 cents per gallon in the last week, prices at local pumps came in at an average cost of $5.24/gallon as of July 20, according to GasBuddy’s survey of 201 stations in Modesto. Prices in Modesto are 23.4 cents per gallon lower than a month ago and stand $1.17/gallon higher than a year ago. The national average price of diesel has decreased 22.3 cents compared to a week ago and stands at $5.077 per gallon.

According to GasBuddy price reports, the cheapest station in Modesto was priced at $4.69/gallon while the most expensive was $6.19, a difference of $1.50/gallon. The lowest price in the state was $3.69 while the highest was $7.59, a difference of $3.90/gallon.

The national average price of gasoline has risen 13.0 cents per gallon in the last week, averaging $3.95/gallon. The national average is up 6.5 cents per gallon from a month ago and stands 85.7 cents per gallon higher than a year ago, according to GasBuddy data compiled from more than 11 million weekly price reports covering over 150,000 gas stations across the country.

Neighboring areas and their current gas prices include: Stockton - $5.22/gallon, up 12.6 cents from last week’s $5.09; Oakland - $5.45/, up 9.5 cents from $5.35; and San Jose - $5.49, up 9.4 cents per gallon from last week’s $5.40/gallon.

“Average gasoline and diesel prices rose in nearly every state for the second straight week, with the national average price of gasoline likely to reach $4 per gallon and diesel already back above $5 per gallon nationally,” said Patrick De Haan, head of petroleum analysis at GasBuddy. “With WTI crude approaching $85 per barrel in Sunday night trading, price-cycling markets are likely to see another jolt higher in the coming days, and motorists should brace for a rougher stretch ahead.”

Historical gasoline prices in Modesto and the national average going back five years show the lowest Modesto price was $4.07 per gallon on July 20, 2025 and the U.S. average low price was $3.09, also in 2025. Highest Modesto average price of $5.65 per gallon was recorded in 2022; highest U.S. average was also on July 20, 2022, coming in at $4.44 per gallon.

GasBuddy, a PDI Technologies company, is North America’s trusted fuel savings platform, helping consumers fuel up for less for over 25 years. With over 100 million app downloads, GasBuddy delivers real-time prices at 150,000+ stations and is the most authoritative source of station-level fuel pricing data, updating averages 288 times daily from the broadest mix of inputs including spotter reports, direct station integrations, and transactional data.