What you actually pay to charge depends on your electricity rate, how much your battery holds, and how often you charge
The cost of charging an electric vehicle is straightforward to work out once you know three numbers: your local electricity rate (in cents per kilowatt-hour), your car's battery capacity (in kilowatt-hours), and how many miles you drive. The math is straightforward enough to do on paper, but the real cost varies depending on whether you charge at home, at a public station, or at a fast charger—and those rates are not the same.
Most EV owners charge at home overnight using standard household electricity, which is usually the cheapest option. Public charging networks charge by the minute, by the kilowatt-hour, or by a flat fee per session, and those rates change by location and network. Understanding how to calculate your own cost takes the guesswork out of whether switching to electric makes financial sense for your driving pattern.
Key Takeaways
- Home charging cost is your electricity rate per kilowatt-hour multiplied by your car's battery size—for example, a 60 kWh battery charged at 15 cents per kWh costs $9 per full charge.
- Public DC fast chargers typically cost 25 to 50 cents per kilowatt-hour, roughly two to four times the home rate, and charge by the minute after 80% to avoid slowing down.
- Your actual cost per mile depends on your car's efficiency rating (miles per kilowatt-hour), which you can find in the owner's manual or on the EPA label.
- Time-of-use electricity rates offered by many utilities charge less during off-peak hours, so charging between 9 p.m. and 6 a.m. can cut your home charging cost by 30 to 50 percent.
- Public charging networks publish their rates online, but comparing them requires checking the specific station location because the same network charges different rates in different cities.
How to calculate home charging cost
Start with your electricity bill. Find the rate you pay per kilowatt-hour—it appears as a line item on your monthly statement, usually labeled "energy charge" or "per kWh rate." If you have time-of-use rates, you will see two or three different rates depending on when you charge. Write down the rate that applies to the hours you plan to charge.
Next, find your car's battery capacity in kilowatt-hours. This is in your owner's manual, on the window sticker when you bought the car, or on the EPA label at fueleconomy.gov. A Tesla Model 3 Standard Range has a 54 kWh battery. A Chevrolet Bolt EV has a 65 kWh battery. A Hyundai Ioniq 6 Standard Range has a 53 kWh battery.
Multiply the battery size by your electricity rate. If you pay 14 cents per kilowatt-hour and your battery is 60 kWh, a full charge costs $8.40. If you pay 18 cents per kilowatt-hour, the same charge costs $10.80. This is the cost to go from empty to full, which most owners do once or twice a week, not every day.
In practice, you rarely charge from completely empty. Most owners charge when the battery reaches 20 percent and stop at 80 percent to preserve battery life. That is 60 percent of the battery's capacity. A 60 kWh battery charged from 20 to 80 percent uses 36 kWh. At 14 cents per kilowatt-hour, that costs $5.04 and adds roughly 120 to 150 miles of range, depending on the car.
How to calculate cost per mile
Your car's efficiency rating tells you how many miles you get per kilowatt-hour. The EPA label lists this as "miles per kWh" or sometimes as "kWh per 100 miles." You can also find it in the owner's manual or by checking your car's trip computer after a full charge.
A Tesla Model 3 Standard Range is rated at 4.1 miles per kilowatt-hour. A Chevrolet Bolt EV is rated at 3.5 miles per kilowatt-hour. A Hyundai Ioniq 6 is rated at 4.8 miles per kilowatt-hour. These are EPA estimates; real-world efficiency varies with weather, driving style, and road conditions.
To find your cost per mile, divide your electricity rate by the efficiency rating. If you pay 14 cents per kilowatt-hour and your car gets 3.5 miles per kilowatt-hour, your cost per mile is 14 ÷ 3.5 = 4 cents per mile. If you pay 18 cents per kilowatt-hour, your cost per mile is 18 ÷ 3.5 = 5.1 cents per mile.
For comparison, a gasoline car that gets 30 miles per gallon costs 3.3 cents per mile at $4 per gallon, and 4 cents per mile at $4.80 per gallon. Your actual savings depend on local electricity and fuel prices, which change over time.
Public charging station rates and how they are structured
Public charging networks do not all charge the same way. Some charge by the kilowatt-hour (like your home electricity bill), some charge by the minute, and some charge a flat fee per session. The same network often uses different pricing models at different stations.
Kilowatt-hour pricing is the clearest to calculate. Electrify America charges 31 to 43 cents per kilowatt-hour depending on location. EVgo charges 26 to 40 cents per kilowatt-hour. ChargePoint varies by station owner. To find the rate at a specific station, open the network's app, search the address, and the rate appears before you plug in. A 30 kWh charge at 35 cents per kilowatt-hour costs $10.50.
Minute-based pricing charges you for time rather than energy. Electrify America charges 0.43 cents per minute at some DC fast chargers. EVgo charges 0.48 cents per minute at some locations. This means a 20-minute charge costs $8.60 to $9.60, but the actual kilowatt-hours transferred depends on how fast the charger is and how full your battery already is. Minute pricing favors fast charging and penalizes slow charging, so it is most common at DC fast chargers where you spend 20 to 40 minutes, not at Level 2 chargers where you might spend 4 to 8 hours.
Flat-fee pricing charges a single price per session regardless of how much energy you use. Some networks charge $2 to $5 per session. This works well if you are topping up for 15 minutes, but it is a poor deal if you are charging for an hour. Check the app before you start charging to see which model applies at that station.
How time-of-use rates reduce home charging cost
Many utilities offer time-of-use (TOU) rates that charge less during off-peak hours, usually late evening through early morning. The difference is significant. Off-peak rates are often 8 to 12 cents per kilowatt-hour, while peak rates during the day can be 20 to 35 cents per kilowatt-hour.
If your utility offers TOU rates, you can see the schedule on your bill or on the utility's website. Most utilities charge off-peak rates between 9 p.m. and 6 a.m. on weekdays, and all day on weekends. Some offer a separate super-off-peak rate between midnight and 6 a.m. that is even cheaper.
Charging during off-peak hours instead of peak hours can cut your cost by 30 to 50 percent. A 60 kWh charge at peak rate (25 cents per kWh) costs $15. The same charge at off-peak rate (10 cents per kWh) costs $6. Over a year, if you charge twice a week, the difference is roughly $900.
To enroll in TOU rates, contact your utility directly. Some utilities require you to opt in; others make TOU the default for EV owners. A few utilities charge a small monthly fee for TOU rates, usually $5 to $15, but the savings from off-peak charging almost always exceed the fee.
Comparing home charging to public charging
Home charging is almost always cheaper than public charging, but the gap depends on your local rates and which public network you use. The table below shows typical costs for a 30 kWh charge (roughly 100 miles of range) under different scenarios.
| Charging Method | Rate | Cost for 30 kWh | Cost per Mile |
|---|---|---|---|
| Home charging (standard rate) | 14 cents/kWh | $4.20 | 1.4 cents |
| Home charging (off-peak TOU) | 10 cents/kWh | $3.00 | 1 cent |
| Public Level 2 charger | 25 cents/kWh | $7.50 | 2.5 cents |
| DC fast charger (low rate) | 31 cents/kWh | $9.30 | 3.1 cents |
| DC fast charger (high rate) | 50 cents/kWh | $15.00 | 5 cents |
Public charging makes sense for road trips where you need to charge quickly and cannot wait for home charging. For daily driving, home charging is almost always cheaper. If you do not have home charging access, a Level 2 charger at work or a nearby public station is the next best option.
Factors that change your actual charging cost
Real-world charging costs vary from the numbers you calculate because of several factors. Battery degradation means older batteries charge less efficiently and require more kilowatt-hours to reach the same range. A five-year-old battery might need 5 to 10 percent more energy than a new one.
Charging losses occur because some energy is lost as heat during the charging process. Home charging loses roughly 10 percent of the energy you pay for. DC fast charging loses 15 to 20 percent. This means a 30 kWh charge at home actually uses about 33 kWh from the grid, and a 30 kWh DC fast charge uses about 36 kWh from the grid.
Weather affects efficiency significantly. Cold temperatures reduce range by 20 to 40 percent, so you need more charges to cover the same distance. Hot weather has a smaller effect, usually 5 to 10 percent range loss.
Driving style changes how far you go on a charge. Aggressive acceleration, highway driving at high speeds, and frequent braking all reduce efficiency. Gentle acceleration, steady speeds, and coasting reduce energy use.
Frequently Asked Questions
How do I find my electricity rate if I do not have a recent bill?
Log into your utility's website using your account number (on any bill or statement) and view your current rate. You can also call your utility's customer service line and ask for your per-kilowatt-hour rate. If you have time-of-use rates, ask for the off-peak rate as well.
Does charging to 100 percent cost more than charging to 80 percent?
Yes, proportionally. Charging from 0 to 80 percent uses 80 percent of the battery's capacity. Charging from 0 to 100 percent uses 100 percent. However, most owners should not regularly charge to 100 percent because it accelerates battery degradation. Charging to 80 percent is the standard practice for daily driving.
Can I use a regular outlet to charge my EV, and how much does it cost?
Yes, but it is very slow. A standard 120-volt household outlet (Level 1 charging) adds roughly 2 to 3 miles of range per hour. A 60 kWh battery would take 20 to 30 hours to charge fully. The cost is the same as your home electricity rate, but the time makes it impractical for regular use. A 240-volt home charger (Level 2) is much faster and is the standard for EV owners.
Why does the same charging network charge different rates in different cities?
Public charging networks set rates based on local electricity costs, demand, and competition. A city with cheap electricity and many chargers has lower rates than a city with expensive electricity and few chargers. Rates also change seasonally and can vary by time of day at the same station.
Should I join a charging network membership to save money?
Only if you use public charging regularly. Most memberships cost $10 to $20 per month and offer a small discount per kilowatt-hour or per minute. If you charge at home most of the time and use public chargers only occasionally, the membership fee will exceed your savings. Calculate your expected public charging cost for a month and compare it to the membership fee.