Guide
How much does it cost to charge an electric car at home?
A home charge costs the energy you put into the car, measured in kWh, multiplied by the price you pay for each kWh. There is no chargepoint fee and no subscription. If you charge 40 kWh at 25p per kWh, that is £10.00.
The price
Where your price per kWh comes from
Your unit rate is set by your electricity supplier and your tariff, not by your car or your charger.
Two things set the price you pay. The first is your tariff, which decides whether you pay one rate all day or a cheaper rate overnight and a more expensive one in the evening. The second is where you live, because the network charges that get built into a tariff vary by region.
If you are on a default tariff, the government sets a limit on what suppliers can charge, published by Ofgem and reset every three months. The headline figure is a national average, so your own bill will be close to it but not identical.
A worked figure, as reviewed on 30 September 2026
26.32p per kWh
Ofgem published 26.32p per kWh as the average default-tariff electricity unit rate for England, Scotland and Wales for the quarter from 1 October to 31 December 2026, for customers paying by Direct Debit. The figure changes every quarter and varies by region, so treat it as a marker rather than a quote. Check your own bill for the rate you actually pay.
- kWh
- Kilowatt hours. One kWh is the amount of energy a one-kilowatt appliance uses in an hour. A home chargepoint adds somewhere around 7 kWh per hour, so a four-hour charge is roughly 28 kWh.
- pence per kWh
- The unit rate on your electricity bill. It is the price of each kWh of energy, and it changes depending on when you use it and which tariff you are on.
- Standing charge
- A fixed daily fee that covers the cost of having a connection at all. You pay it whether or not you charge a car, so it is not part of the cost of a single session.
- Charging losses
- Energy that leaves the charger as heat instead of reaching the battery. This is why the meter usually records a little more than the car gained.
Work it out
Work out the cost of a charge
Multiply the energy added by your electricity price, as in the example below.
Take an overnight charge. The car gained 40 kWh, and your tariff charges 25p per kWh during that window. Multiplying the two gives the energy cost of the session in pence, which you then divide by 100 to get pounds.
Energy added to the car: 40 kWh
Price of that energy: 25p per kWh
40 multiplied by 25 is 1,000p
1,000p is £10.00
If you make this charge every week, the electricity price makes a difference to your running costs. Halving the unit rate by charging on a cheaper overnight tariff halves the cost of every charge.
Meter or car?
Why your meter reads more than the car gained
Both numbers are correct. They answer different questions.
A charger sends alternating current to the car, and the car converts it into the direct current a battery needs. That conversion is not perfect. Some energy is lost as heat in the cable, the charger and the car, and that heat was still paid for.
So there are two figures, and you should be clear which one you are using:
- Energy added to the car is what the car reports it stored. It is the fairer number to compare against how far you drove, but it understates what you were billed.
- Energy on your meter is what actually crossed the supply. Use this if you want the true cost of the session, and expect it to be higher.
There is no single efficiency figure that fits every car, every charger and every night. Cold weather and a long cable both make the gap wider. Rather than guess a percentage, pick one of the two figures and stay with it when you compare sessions.
Not included
Which costs are not included?
A per-charge figure is not the same thing as your electricity bill.
When you work out the cost of a charge, several things are deliberately left out. None of them are mistakes, but all of them are worth knowing about.
- Charging at more than one price. A single rate is applied to the whole session. If a charge spans an off-peak boundary, the real cost is somewhere between the two rates.
- Tariff features. Some tariffs have a subscription, or require you to use an app to get the cheap rate. If you do not meet the conditions, the rate changes.
- The chargepoint grant. The government grant pays part of the installation cost, not your energy bill. It does not lower the price of a kWh.
One more background note. UK domestic electricity rates are normally quoted with VAT already included, so the number on your bill is what you pay. VAT policy on domestic energy is something governments change from time to time, so if you are comparing bills over a long period, it is worth checking whether the tax position was the same throughout.
What this means for you
Plan your charging costs
Most people find the answer is about timing rather than hardware. Once you have a charger that can be told when to charge, moving that window to a cheaper rate changes the running cost far more than upgrading the charger itself.
- Check whether your readings show energy added to the battery or electricity used for charging. Use the same type of reading when comparing charges.
- If you are on a time-of-use tariff, check what your charger can do before changing tariff. Scheduling usually needs a smart charger.
- Treat any single session figure as an estimate. Charging at home is generally the cheapest way to fill a battery, and public rapid charging is priced differently, so the two are not comparable line for line.
Once you know which figure matters to you, the next question is what installation involves. That is covered in what happens when a charger is installed, and the speed question that affects whether you can shift your charging window at all is in 7 kW versus 22 kW.
Further reading
Sources
- Last reviewed
- Energy price cap unit rates and standing charges — Ofgem. Average default-tariff electricity unit rates and standing charges, updated each quarter.
- Energy price cap rates, 1 October to 31 December 2026 — Ofgem. The rate that applies to the quarter beginning 1 October 2026.
- Charging electric vehicles — Energy Saving Trust. Consumer guidance on home charging and what affects the cost of a charge.
- Electric vehicle chargepoint grants — Office for Zero Emission Vehicles, GOV.UK. What the current grants pay for, and what they do not.