San Antonio residents who are feeling the sting at the gas pump aren't alone: Residents all around Texas are seeing soaring prices for regular and diesel fuel in 2026.

In fact, the Lone Star State has seen the fifth-highest percentage increase in gas prices in the country from April 2025 to April 2026, a just-released SmartAsset study has found. The current cost of a regular gallon of gas is 36.1 percent higher now than it was a year ago, and diesel is 60.9 percent more expensive.

The report, "Gas Prices Hit Records in 2026: State by State Breakdown," compared average gas prices from AAA from April 1, 2025, and April 1, 2026, and calculated the one-year change across all 50 states. The study looked at the price of a gallon of regular, premium, and diesel.

According to AAA, the cost of a regular gallon of gas in Texas at the start of April was $3.77, while premium is $4.62 per gallon. Diesel ticked over $5 a gallon — ouch — at $5.11.

Regular and diesel prices in San Antonio are even costlier. A gallon of regular costs up to $3.87 at some San Antonio-area pumps, and diesel is $5.26 per gallon. AAA says the highest recorded average price for gas in the city was in June 2022, when a gallon of regular cost $4.69. Diesel reached its highest peak in May 2022 at $5.30 per gallon.

Though Texas' gas prices are continuing to climb, it ranks 35th in the national ranking of states with the highest cost for regular gas as of April 2026. Texas' diesel prices are the 14th highest nationwide.

With the national average price for gas at $4.06, SmartAsset said the sudden surge in prices can be attributed to the United States' war on Iran, and "subsequent pressure on the Strait of Hormuz."

"Many states have experienced a 33 percent year-over-year increase in the cost of a gallon of regular gas – and in some places it’s even higher," the report's author wrote. "Commercial and public programs may be feeling similarly pinched, with diesel prices upwards of $6.00 per gallon in many states."

California currently has the highest average price for regular and diesel — $5.89 per gallon and $7.52 per gallon, respectively.

Arizona leads the nation with the highest one-year increase in gas prices. Regular gas in the Grand Canyon State is nearly 38 percent more expensive than it was last year, at $4.70 per gallon, and diesel is about 69 percent higher at $6.04 for a gallon.

The state with the cheapest gas prices in April is Oklahoma, where regular costs $3.27 per gallon, premium is $3.97, and diesel is $4.49.