California has the highest state gasoline tax at this moment, but the ranking changes
California's state gasoline tax is currently the highest in the nation, but the exact amount varies week to week because it is tied to the price of fuel. As of early 2024, California's excise tax on gasoline sits around 68 cents per gallon when combined with its sales tax on fuel. However, Washington State, Hawaii, and Illinois also charge among the highest per-gallon taxes in the country, and the order shifts depending on how you measure it—whether you count only the excise tax, the sales tax, or both combined.
The reason the rankings shift is that some states use a flat excise tax (a set number of cents per gallon) while others explore a percentage-based sales tax on top of the fuel price. When gas prices rise, states with sales taxes see their total tax per gallon climb. When prices fall, so does the tax. States with only a flat excise tax stay the same regardless of what you pay at the pump.
Understanding which state charges the most matters if you live near a state border, drive for work, or are curious about how your state's fuel costs compare. The difference between the highest and lowest state tax can be 50 cents per gallon or more, which adds up quickly for regular drivers.
Key Takeaways
- California currently has the highest combined state gasoline tax, but Washington, Hawaii, and Illinois are also in the top tier.
- Some states use a flat per-gallon excise tax while others use a percentage-based sales tax, which is why rankings change when fuel prices move.
- The difference between the highest-taxed and lowest-taxed states can exceed 50 cents per gallon.
- Federal gasoline tax is the same everywhere at 18.4 cents per gallon, but state taxes vary widely.
- Tax rates are set by state legislatures and change periodically, so the highest-taxed state may shift over time.
How state gasoline taxes are structured
States use two main methods to tax gasoline: a flat excise tax or a percentage sales tax. An excise tax is a fixed number of cents added to every gallon sold, regardless of the price. A sales tax is a percentage of the total price you pay, so it rises and falls with fuel prices.
California uses a combination of both. It charges a flat excise tax of around 51 cents per gallon, then adds a sales tax on top of that. When you buy gas in California, you also pay the state's standard sales tax rate, which varies by county but averages around 7.25 percent. This dual approach is why California's total tax per gallon is so high—you are paying cents per gallon plus a percentage of the price.
Washington State charges one of the highest flat excise taxes at around 49.4 cents per gallon, with no additional sales tax on fuel. Hawaii charges around 42 cents per gallon in excise tax plus sales tax. Illinois charges around 38 cents per gallon in excise tax plus sales tax. The way each state structures its tax affects how much you pay and whether the tax goes up or down when fuel prices change.
Why California and Washington rank at the top
California and Washington have the highest gasoline taxes largely because both states have made deliberate policy choices to fund transportation infrastructure and environmental programs through fuel taxation. California's tax revenue supports road maintenance, public transit, and environmental initiatives. Washington's high excise tax similarly funds transportation projects.
Both states also have higher costs of living and higher infrastructure expenses than many other states, which creates pressure to raise fuel taxes to cover those costs. Additionally, both states have environmental policies that sometimes include fuel taxes as a way to encourage fuel efficiency and reduce consumption.
It is worth noting that high fuel taxes do not necessarily mean drivers pay more total tax per year—that depends on how much you drive. A person who drives 5,000 miles per year in California pays less total fuel tax than someone who drives 20,000 miles per year in a low-tax state. The per-gallon rate is only one part of the picture.
States with the lowest gasoline taxes
On the opposite end, Alaska, Mississippi, and South Carolina charge some of the lowest state gasoline taxes in the nation. Alaska's state excise tax is around 14.7 cents per gallon. Mississippi charges around 18.4 cents per gallon. South Carolina charges around 21.6 cents per gallon. These states rely less on fuel taxation to fund transportation and instead use other revenue sources like general sales tax or vehicle registration fees.
The gap between the highest and lowest is substantial. A driver filling a 15-gallon tank in California pays roughly $10 more in state tax alone than a driver in Alaska filling the same tank. Over a year, that difference compounds significantly for regular drivers.
How federal tax fits into the total
On top of state taxes, the federal government charges 18.4 cents per gallon on gasoline. This federal excise tax is the same in every state and goes toward the Highway Trust Fund, which supports interstate highways and transportation projects nationwide. You pay this federal tax whether you live in California or Alaska.
When you see the total tax per gallon at the pump, you are looking at federal tax plus state tax combined. In California, that means roughly 18.4 cents federal plus around 68 cents state, for a total of about 86 cents per gallon in tax alone. In Alaska, it is 18.4 cents federal plus around 14.7 cents state, for a total of about 33 cents per gallon.
When and why state gasoline taxes change
State legislatures set gasoline tax rates, and they change periodically through new laws. Some states adjust their taxes annually based on inflation or transportation funding needs. Others keep rates flat for years and then raise them in a single vote. A few states, like Hawaii and Washington, have automatic adjustment mechanisms that tie the tax to inflation or fuel prices.
States raise fuel taxes when they need more money for road repairs, bridge maintenance, or public transit projects. They lower taxes less often, but it does happen—usually when a state faces budget pressure or political pressure from drivers. The timing and amount of changes vary widely by state, so the ranking of highest-taxed states can shift over months or years.
If you are tracking gasoline taxes for budgeting or comparison purposes, checking your state's Department of Transportation or Department of Revenue website will show you the current rate. These rates are public information and updated regularly.
How to find your state's current gasoline tax rate
Your state's Department of Transportation or Department of Revenue publishes the current gasoline tax rate. You can also find a comparison of all 50 states' rates through the American Petroleum Institute or the Tax Foundation, both of which maintain updated lists. These resources show the flat excise tax, any sales tax applied to fuel, and the combined total.
Keep in mind that some states allow local governments to add their own fuel taxes on top of the state rate, so your actual total tax per gallon may be slightly higher than the state rate alone. A few counties or cities in certain states charge an additional local fuel tax, though this is less common than it once was.
Frequently Asked Questions
Does the federal gasoline tax change by state?
No. The federal excise tax is 18.4 cents per gallon everywhere in the United States. Only state and local taxes vary. You pay the same federal tax whether you fill up in California or Alaska.
Why do some states have much higher gasoline taxes than others?
States set their own tax rates based on their transportation funding needs, infrastructure costs, and political choices. States with higher costs of living, more extensive road systems, or stronger environmental policies tend to charge higher fuel taxes. Some states also rely more heavily on fuel taxes than on other revenue sources.
If I drive across a state border, do I pay different taxes?
Yes. You pay the gasoline tax of the state where you buy the fuel. If you fill up in a low-tax state and drive to a high-tax state, you do not owe the difference. You only pay the tax at the pump where you purchase.
Can a state lower its gasoline tax?
Yes, though it happens rarely. States lower fuel taxes when facing budget pressure or political pressure from voters. Most changes are increases, not decreases, because states need more money for road maintenance as infrastructure ages.
Is the gasoline tax the same price every day?
The state excise tax (flat per-gallon rate) stays the same. However, if your state uses a sales tax on fuel, the total tax per gallon changes daily as the fuel price changes. This is why your total cost per gallon fluctuates even when the state tax rate itself does not.