Gas prices in Chicago, IL

About gas prices in Chicago, IL

Chicago drivers face one of the country's most layered tax structures. Illinois charges a state motor fuel tax, Cook County adds its own per-gallon excise, and the city of Chicago layers on additional taxes. A Chicago city station can cost 20 to 35 cents more per gallon than an Indiana border station less than 10 miles away. Reformulated gasoline (RFG) is required in the metro region through summer ozone season, which limits supply flexibility. The BP Whiting refinery, just over the Indiana line, is the dominant supplier, and any disruption there ripples into Chicago retail within 3 to 7 days. Drivers who plan around tax boundaries and warehouse clubs (Costco locations in the suburbs especially) can save more than $5 per fill-up versus city-center pricing.