US Petrol Prices Surge, Spiking in Trump-Supporting Regions
The war in the Middle East is causing fuel prices in the United States to continue soaring across various states, although the rate of increase varies significantly.
Using AAA Fuel Price data from 18 February 2026 as a pre-war baseline and comparing it to prices on 20 August 2026, data illustrates the percentage increases across all 50 states. The highest increases are primarily located in regions that supported US President Donald Trump following his 2024 election victory.
Iowa experienced the largest percentage increase, with petrol prices jumping 69.1% from US$2.45 to US$4.14 per gallon. Oklahoma followed at 68.8%, while Colorado, Minnesota, and Wyoming each saw increases of more as much as 60%. Montana, New Mexico, North Dakota, South Dakota, and Kansas completed the top ten, each rising by more than 57%.
Many states with the highest percentage increases started from relatively low pre-war prices, which magnified the percentage change as crude oil prices rose. Oklahoma, for instance, had the lowest base price in the country at US$2.29 per gallon, which has since risen by nearly 69%.
Nationwide, the average increase reached approximately US$1.25 per gallon (roughly 44% from pre-war prices). This represents an additional US$15 for a full 12-gallon tank. With estimated annual fuel consumption at approximately 450 gallons per vehicle, according to Federal Highway Administration data, a sustained increase of US$1.25 per gallon will add about US$560 to annual fuel costs.
The surge follows major global oil supply disruptions caused by the Iran War, which closed the Strait of Hormuz, driving oil prices sharply higher as approximately 10 million barrels per day were removed from the market.
The impact extends far beyond the petrol pump. As one barrel of crude oil supplies thousands of products daily—ranging from plastics to pharmaceuticals—the rise in crude oil prices could have widespread implications for the overall economy.
States with the smallest percentage increases are largely those that were already paying the highest prices. High fuel taxes and climate-related fuel policies, including carbon pricing programmes in California and Washington, help keep base prices high. California also utilises state-mandated fuel blends that are difficult to supplement with petrol from outside the state.
Hawaii faces different constraints; as an archipelago without pipeline access, its fuel must be shipped from elsewhere, adding constant logistical costs to every gallon. California experienced the smallest increase at 21.8%, followed by Hawaii at 23.4% and Washington at 25.7%. However, these three states remain the most expensive in the country, with prices at US$5.59, US$5.43, and US$5.24 per gallon, respectively.