UNDATED – Average gasoline prices in South Dakota have risen 18.0 cents per gallon in the last week, averaging $3.82/g today, according to GasBuddy’s survey of 628 stations in South Dakota. Prices in South Dakota are 3.2 cents per gallon higher than a month ago and stand 91.4 cents per 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 South Dakota was priced at $3.45/g yesterday while the most expensive was $4.44/g, a difference of 99.0 cents per gallon. The lowest price in the state yesterday was $3.45/g while the highest was $4.44/g, a difference of 99.0 cents per gallon.

The national average price of gasoline has risen 13.0 cents per gallon in the last week, averaging $3.95/g today. 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.

Historical gasoline prices in South Dakota and the national average going back five years:
July 20, 2025: $2.91/g (U.S. Average: $3.09/g)
July 20, 2024: $3.16/g (U.S. Average: $3.47/g)
July 20, 2023: $3.43/g (U.S. Average: $3.55/g)
July 20, 2022: $4.41/g (U.S. Average: $4.44/g)
July 20, 2021: $3.10/g (U.S. Average: $3.17/g)

Neighboring areas and their current gas prices:
Sioux Falls- $3.84/g, up 22.7 cents per gallon from last week’s $3.61/g.
North Dakota- $3.69/g, up 11.6 cents per gallon from last week’s $3.57/g.
Nebraska- $3.81/g, up 24.7 cents per gallon from last week’s $3.56/g.

“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 within the next 48 hours and diesel already back above $5 per gallon nationally,” said Patrick De Haan, head of petroleum analysis at GasBuddy. “While the ongoing U.S.-Iran situation continues to weigh on markets, the story is increasingly less about crude oil and more about global refining capacity — the Strait of Hormuz remains closed while continued Ukrainian attacks on Russian refineries further squeeze an already strained supply picture. 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.”