A more fuel-efficient vehicle saves money each mile, but paying a large price premium for better MPG does not always produce the lowest total cost.
Example: 25 MPG vs 35 MPG
Assume both vehicles travel 12,000 miles per year and gasoline costs $4.085 per gallon.
25 MPG vehicle
12,000 ÷ 25 = 480 gallons
480 × $4.085 = approximately $1,961 per year
35 MPG vehicle
12,000 ÷ 35 = approximately 343 gallons
343 × $4.085 = approximately $1,401 per year
The 35-MPG vehicle saves roughly $560 per year in gasoline.
What if the efficient car costs $3,000 more?
$3,000 ÷ $560 ≈ 5.4 years
At similar mileage and gasoline prices, it would take a little over five years of fuel savings to recover the $3,000 price difference.
Annual mileage changes the payback
A high-mileage commuter saves more fuel each year than a driver who travels only a few thousand miles. More annual mileage generally shortens the fuel-savings payback period.
Do not ignore the rest of the vehicle cost
Resale value, depreciation, insurance, financing and maintenance can outweigh fuel savings. Better MPG should therefore be evaluated as one component of the full ownership cost.
Source
U.S. Energy Information Administration Weekly Retail Gasoline Prices, August 24, 2026.