Gas Tax by State Calculator
Gas taxes in the United States are levied per gallon by both the federal government and each state. The federal gasoline excise tax is $0.184 per gallon (set in 1993). State gas taxes range from about $0.09 per gallon in Alaska to over $0.60 per gallon in California when including state fees. The combined rate determines how much of every dollar at the pump goes to governments. Enter the number of gallons purchased and the combined (federal plus state) per-gallon rate to calculate total fuel tax paid.
Gas tax formula
Total Fuel Tax = Gallons x Combined Per-Gallon Rate
The per-gallon rate is the sum of the federal excise ($0.184 for gasoline, $0.244 for diesel) and your state's excise rate. For annual fuel tax cost, multiply total annual gallons (miles driven / MPG) by the combined rate.
Sample combined gas tax rates (gasoline, 2024 approximate)
- Federal: $0.184 per gallon (all states)
- California: approximately $0.59 state excise + fees (combined with federal, approximately $0.77)
- Pennsylvania: approximately $0.587 state (combined approximately $0.77)
- Texas: $0.20 state (combined approximately $0.38)
- Alaska: $0.09 state (combined approximately $0.27)
Verify current state rates with your state Department of Revenue or the American Petroleum Institute (API) state motor fuel tax report.
Gas tax FAQ
What is the federal gas tax rate?
The federal excise tax on gasoline is $0.184 per gallon and on diesel is $0.244 per gallon. These rates have been unchanged since 1993. The federal gas tax funds the Highway Trust Fund, which finances interstate highway construction and maintenance.
Which states have the highest gas taxes?
As of 2024, the states with the highest combined (state + local) gas taxes include California, Pennsylvania, Illinois, and Washington. California's total state excise, sales tax on fuel, and fees can push the effective rate well above $0.70 per gallon. State rates change frequently; verify with your state's Department of Revenue.
How does gas tax differ from sales tax on fuel?
Gas taxes are per-gallon excise taxes, not ad valorem (percentage) taxes. However, some states also levy their general sales tax on top of the excise tax, calculated on the price including the excise. This stacking of taxes can significantly increase the total tax burden at the pump.
Does the gas tax apply to diesel and other fuels?
Yes, but at different rates. The federal diesel excise is $0.244 per gallon. Alternative fuels such as propane and compressed natural gas also have their own federal excise rates. State fuel taxes typically apply to diesel and gasoline at similar but often different rates.
Are commercial fuel buyers exempt from gas tax?
Some uses qualify for refunds of the federal gas tax, such as off-road use in farming or construction (Form 4136), use by governments, and use as a fuel for aircraft. State exemptions vary. Fuel used in interstate trucks and buses is subject to the International Fuel Tax Agreement (IFTA).
Official sources
- IRS: Federal Excise Tax on Fuel: IRS Excise Tax.
- Tax Foundation: State Gas Tax Rates.
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.