Impact on your electricity bill will vary based on your electricity rate, how many miles per kWh your vehicle charges, and your driving habits.
To understand the cost of electric car charging at home, check your vehicle efficiency, measured in kilowatt-hours per 100 miles driven. Electricity is also priced in kilowatt-hours, making the math easier. Take the number of kilowatt-hours your car uses to travel 100 miles and multiply that by what you pay for a kilowatt-hour in your home. Divide that number by 100 and you’ve got your cost per mile.
For example, a car that’s rated at 33 kilowatt-hours per 100 miles, charged with electricity costing $0.13 per kilowatt hour, will run you 4 cents a mile.