How much was the federal tax on 10 gallons of gas?
Federal tax on 10 gallons of gas was $0.40 in 1970 and $1.84 in 2025: about 4.6 times as much.
Over the same years, prices in general (US inflation, measured by the consumer price index, CPI) rose about 8.3 times. That makes $0.40 in 1970 worth about $3.32 in 2025 money. So it fell behind inflation: about 45% less, in real terms, than in 1970.
The biggest change between two listed years came between 1980 and 1985, when it went up 125%, from $0.40 to $0.90.
NOTE: the tax is shown for 10 gallons so the cents are exact. Per gallon it is a tenth of these amounts.
Federal gas tax: price by year
| Year | Amount | In 2025 dollars |
|---|---|---|
| 1970 | $0.40 | $3.32 |
| 1980 | $0.40 | $1.56 |
| 1985 | $0.90 | $2.69 |
| 1988 | $0.91 | $2.48 |
| 1992 | $1.41 | $3.24 |
| 2025 | $1.84 | $1.84 |
"In 2025 dollars" adjusts each amount for inflation with the CPI, so the years can be compared fairly. How this works.
Where the numbers come from
Figures as published by the source below.
Source: Federal Highway Administration: Highway Statistics 2024, Table FE-101A: Federal Tax Rates on Motor Fuels and Lubricating Oil (FHWA, November 2025). View the source.
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