How Much Does It Cost to Charge an EV at Home?

Charging an EV at home costs the energy you add times your electricity rate, plus a small loss for charging inefficiency. Enter your own rate and the math is straightforward and exact.

Results are estimates for planning and education, based on your inputs and standard engineering values (AWG resistance, NEC ampacity, resistivity). Electrical work can be dangerous and is governed by the NEC and your local code — verify all sizing with a licensed electrician and your authority having jurisdiction (AHJ). Not a substitute for professional design.

The basic idea: energy times your rate

Charging an electric vehicle at home is, at heart, the same calculation as running any appliance: the energy you draw from the wall multiplied by the price you pay per kilowatt-hour. The only wrinkles are that you usually charge a portion of the battery (say 20% to 80%) rather than the whole thing, and that some energy is lost as heat during charging so the wall draws a little more than reaches the battery. This site never hardcodes electricity prices: you enter your own rate, which keeps the answer correct no matter how tariffs change.

The formulas

Start with the energy that must reach the battery:

energy to battery = battery kWh × (target% − start%) / 100

Account for charging losses with an efficiency factor (about 0.9 is typical for Level 2 home charging) to get the energy actually pulled from the wall:

energy from wall = energy to battery / efficiency

Then the cost is just the wall energy times your rate, and the charge time is the battery energy divided by the charger’s power:

cost = energy from wall × rate | charge time = energy to battery / charger kW

Worked example: 60 kWh battery, 20% to 80%

Take a 60 kWh battery charged from 20% to 80% on a 7.2 kW Level 2 charger at 90% efficiency, and suppose your rate is $0.15 per kWh (substitute your own):

Energy to battery: 60 × (80 − 20) / 100 = 60 × 0.6 = 36 kWh.
Energy from wall: 36 / 0.9 = 40 kWh.
Cost: 40 × $0.15 = $6.00.
Charge time: 36 / 7.2 = 5.0 hours.

So this 60% top-up adds about 36 kWh to the battery, pulls 40 kWh from the wall, costs six dollars at the example rate, and takes five hours. The EV Charging Cost calculator runs these numbers with your battery size, charge window, charger power, efficiency and rate.

Why home charging is cheap

Home charging is almost always the least expensive way to fuel an EV, because residential electricity rates are far below the per-kWh price of public DC fast charging. Charging overnight on an off-peak or time-of-use rate, where available, cuts the cost further — you simply enter that lower rate. Because you supply the rate, the calculator reflects your exact situation, including solar self-consumption (enter a very low or zero rate for energy you generate yourself).

Charge time and charger level

Charge time depends on the charger’s power, not the cost. A Level 1 (120 V) charger delivers roughly 1.4 kW and is slow — good for overnight top-ups of a few percent. A Level 2 (240 V) home charger delivers anywhere from 3.8 to 11.5 kW and handles a full daily replenishment overnight. In the example, halving the charger to 3.6 kW would double the time to 10 hours while leaving the cost unchanged, because the same energy is delivered either way.

Cost per mile, the figure that matters

The cost of a single charge is useful, but the number that lets you compare an electric car with a gasoline one is the cost per mile. To find it, divide the energy a trip consumes by the distance, then multiply by your rate. Many electric vehicles use somewhere around a quarter to a third of a kilowatt-hour per mile, so a car that uses thirty kilowatt-hours per hundred miles costs thirty times your rate to drive that hundred miles. Because you supply the rate, the calculator reflects your exact situation, and the comparison with gasoline becomes a simple matter of dividing the fuel cost per mile each way. For most drivers on residential power the electric cost per mile comes out a fraction of the gasoline figure.

Why off-peak rates change everything

Charging is one of the few large household loads you can shift in time, and that flexibility is valuable wherever a utility offers time-of-use pricing. If overnight power is cheaper than daytime power, scheduling the charge for the off-peak window can cut the cost of every mile substantially, and most vehicles and home chargers can be set to start at a chosen hour. Because the calculator takes the rate you enter, you can run the numbers at your peak rate and again at your off-peak rate to see the difference in dollars over a year of driving. This is also where home charging pulls furthest ahead of public fast charging, which is priced for convenience rather than for the low overnight cost of residential energy.

Charging from your own solar

If you generate your own power, the marginal cost of the energy you use yourself can be very low, and the same formula handles it: simply enter a rate that reflects the value of your self-generated electricity, which may be near zero for energy that would otherwise be exported at a low price. Charging during the day when panels are producing lets a vehicle soak up surplus solar that would otherwise be sold back cheaply, effectively turning the car into a flexible load that improves your self-consumption. The calculation does not change; only the rate you supply does, which is the whole point of keeping prices out of the tool and in your hands.

Efficiency losses you do not see

The gap between the energy that reaches the battery and the energy drawn from the wall is real money, so it is worth understanding. Charging losses appear as heat in the onboard charger and the battery, and they are larger in cold weather, when the car may also spend energy warming the battery before it will accept a charge. Level one charging from a standard outlet tends to be a little less efficient than level two because the fixed overhead is spread over a slower trickle. None of this is a reason to worry, but it does mean the wall energy, and therefore the cost, runs modestly above the battery energy, which is exactly why the formula divides by an efficiency factor before applying your rate.

Putting it in context

To compare an EV against the running cost of other household loads, the same energy-times-rate logic applies; the Appliance Energy Cost calculator and Electricity (kWh) Cost calculator use it for anything that plugs in. Because every figure here is either a physical quantity or a rate you supply, the result needs no maintenance — it is correct today and will be correct whatever happens to energy prices. Treat the efficiency (about 0.9) as an estimate; your real losses depend on temperature, charger and battery.

Frequently asked questions

How much does it cost to charge an EV at home?

It is the energy drawn from the wall times your electricity rate. For a 60 kWh battery charged 20 to 80 percent at 90 percent efficiency, you add 36 kWh to the battery and pull 40 kWh from the wall; at an example rate of $0.15/kWh that is $6.00. Enter your own rate for an exact figure.

Why does the wall draw more energy than the battery stores?

Because charging is not perfectly efficient; some energy is lost as heat in the charger and battery. A typical Level 2 efficiency is about 90 percent, so adding 36 kWh to the battery pulls about 40 kWh from the wall. Divide battery energy by the efficiency to get wall energy.

How long does it take to charge an EV at home?

Charge time is the energy added to the battery divided by the charger power. Adding 36 kWh on a 7.2 kW Level 2 charger takes 36 / 7.2 = 5 hours. A slower charger takes proportionally longer but costs the same, since the same energy is delivered.

Is home charging cheaper than public charging?

Almost always. Residential electricity rates are well below the per-kilowatt-hour price of public DC fast charging, and off-peak or time-of-use rates cut the home cost further. Because you enter your own rate, the calculator reflects your exact tariff, including solar self-consumption.