Estimate only. Time-of-use rates, public fast charging and cold weather change the real cost.
How the cost is calculated
- Electricity: miles per month × your EV's energy use (kWh per 100 miles) ÷ 100.
- Charging cost: that electricity × your state's average residential price (EIA, Table 5.6.B).
- Gasoline cost: miles per month ÷ the gas car's mpg × the price per gallon.
Which energy use to enter
Use the kWh/100 mi from your EV's EPA label or fueleconomy.gov. If you use the number on your car's screen instead, it may count only the energy in the battery: add charging losses, since charging efficiency is often 84% to 93% (fueleconomy.gov).
Default values
- Gasoline: $3.10 per gallon, the 2025 U.S. average for regular gasoline (EIA). Prices vary by state and week.
- Gas car: 27.2 mpg, the average real-world fuel economy of new model year 2024 vehicles (EPA Automotive Trends).
If your utility has a cheaper overnight rate for EV charging, your savings will be higher than shown.
Example: cost per mile
An EV that uses 30 kWh per 100 miles costs about 10.0¢ per mile to charge at home in California (33.25¢ per kWh), 4.8¢ in Texas (16.06¢) and 13.9¢ in Hawaii (46.28¢). A 27.2 mpg gas car at $3.10 per gallon costs about 11.4¢ per mile in fuel. The table below shows 1,000 miles a month in six states.
How to find your EV's energy use
Use the kWh per 100 miles on the EPA label or on fueleconomy.gov. If you read the number on the car's screen, add charging losses: the screen often counts only the energy that reaches the battery.
How to read your result
- Monthly charging cost is your miles × energy use × your state's average residential electricity price.
- Gas cost uses the price and mpg you enter. Change them to match the car you would otherwise drive.
- Savings are the difference, per month and per year.
How to pay less for charging
- Charge off-peak. Many utilities have time-of-use or EV rates with lower prices at night. Your savings can be much higher than the average price shows.
- Use Level 2 at home instead of public fast chargers, which usually cost more per kWh.
- Charge with solar if you have panels: midday charging uses your own production.