How Much Does It Cost to Charge an EV Per Month?

Three steps: energy the car uses, energy drawn from the grid, and what that energy costs.

Use your own odometer or app history. Monthly distance varies — holidays, school terms and long trips can double a month — so either use a 12-month average for a yearly budget, or calculate high and low months separately if you need to plan cash flow. Long trips usually also shift charging from home to public chargers, which changes the price per kWh as well as the kWh.

Consumption is quoted in several units. They convert exactly:

• 1 kWh/100 km = 10 Wh/km
• Wh/mi = Wh/km × 1.609344 (1 mile = 1.609344 km)
• mi/kWh = 1,000 ÷ Wh/mi; km/kWh = 100 ÷ kWh/100 km

Illustrative: 17 kWh/100 km = 170 Wh/km = 170 × 1.609344 ≈ 273.6 Wh/mi ≈ 3.65 mi/kWh. The Wh/mi to Wh/km converter does this for any value.

The best source is your own car's average over several months. Official figures come from standardised tests (WLTP in Europe, the EPA label in the US) with different procedures, so compare cars only using figures from the same source, and expect real use to differ.

Not every consumption figure measures the same energy:

• Trip computers usually report energy taken from the battery while driving. That does not include charging losses — check your car's manual.
• Official test figures are measured from the mains supply during recharging, so they include charging losses: the US EPA label's electricity consumption includes energy lost during charging (fueleconomy.gov, EV label explained), and the WLTP procedure (UN GTR No. 15) measures recharged energy from the mains.
• Your charger or smart meter reports the energy you actually pay for at home.

If you use a battery-side figure, divide by a charging efficiency. If you use an official wall-based figure, do not divide again.

Some energy is lost as heat in the car's onboard charger, cables and battery during charging, and some is used by battery heating or cooling and the car's electronics while it charges. The share depends on the car, charging power, battery temperature and whether the car is heating the battery in cold weather. There is no universal figure.

To find your own: compare the kWh your home charger or a dedicated meter recorded with the kWh the car reports added over the same sessions. Otherwise treat efficiency as an assumption and test a range.

Use the unit rate (price per kWh) from your bill. Standing or fixed daily charges are paid whether or not you charge a car, so do not add them to the EV cost. If your tariff has tiered or block pricing, the extra kWh for the car fall into your highest tier — use that rate.

An EV can add a significant number of kWh to a household bill. Compare the monthly kWh from the formula with your current monthly consumption to see the increase, and check whether your supply and fuse rating suit the charger you plan to use; the Home Charger Sizing tool helps with charger power for your driving.

With a time-of-use tariff, the price depends on when you charge. Use a weighted price for the share of kWh charged in each period:

Weighted price = Σ (Share of kWh in period × Price in period)

Read the tariff's full terms: some EV tariffs change the rate for all household use, not just the car, so compare the whole bill, not only the car's share.

Public charging can be priced in several ways, sometimes combined:

• Per kWh — the easiest to compare with your home rate.
• Per minute — the cost per kWh then depends on how fast your car actually charges.
• Session or connection fee — a fixed amount per charge.
• Subscription or membership — a monthly fee that lowers the per-kWh price.
• Idle fees — charges for staying connected after charging ends.

Convert each to a price per kWh before comparing. Check the price shown by the network or app before you charge; prices vary by network, location, charger speed and time.

When you charge in more than one place, use a blended price: home share × home price + public share × public price. The table uses the base example (236.1 kWh drawn per month) with an illustrative €0.28/kWh at home and €0.65/kWh public, and applies the same 90% efficiency to both for simplicity:

Consumption is usually higher in cold weather: the cabin and battery need heating, and a cold battery is less efficient. How much higher depends on the car, climate, trip length and whether you pre-heat while plugged in. Rather than applying a general percentage, compare your own winter and summer averages from the trip computer and calculate each season separately — or use a full year's average for an annual budget.

Each scenario uses its own complete, illustrative inputs. None represents a national average or a real tariff.

1. Check for an off-peak or EV tariff — the saving is the kWh you shift × the difference between rates. Compare the tariff's full terms, including the rate for the rest of your household use.
2. Schedule charging — a car or charger timer uses cheaper hours without changing habits.
3. Charge at home where possible — the blended price rises quickly with public charging if public prices are higher than your home rate.
4. Pre-heat while plugged in — the energy then comes from the grid, not the battery.
5. Charge from rooftop solar — daytime charging can use your own output; see the solar payback guide for how self-consumption affects solar economics.

The EV Charging Cost Calculator applies the same formula: enter consumption, charging efficiency, home and public prices, the home share and annual distance. It returns energy drawn from the grid, cost per 100 km and annual cost (divide by 12 for a monthly figure). The methodology page documents its formulas, and the Electric Vehicles hub collects related tools.

Related next questions:

• How long will a charge take, and what does one session cost? — the EV charging time and cost guide.
• What charger power do I need at home? — the Home Charger Sizing tool.
• How does an EV's running cost compare with a petrol car? — the EV vs petrol running cost comparison.