How Much Does It Cost to Charge an Electric Car in the UK?

“A full charge” is a favourite headline number, but it answers the wrong question. The cost of filling the battery says nothing about how far that energy takes you, or how often you need to buy it.

Two cars with the same battery size can cost very different amounts to run. One might travel 3.5 miles on each kWh; another might manage only 2.5. The less efficient car buys more electricity for the same journey, whatever the tariff.

Cost per mile is the number that matters — and it depends on both efficiency and price.

The arithmetic is simple: the energy your car uses, multiplied by the electricity price you pay for it. Charging losses add to the first part, because a car takes slightly more energy from the charger than ends up in the battery.

Energy from the charger = energy into the battery ÷ charging efficiency.

For planning, we will use one example car throughout:

• 60kWh usable battery
• 3.5 miles per kWh efficiency (illustrative)
• 10% charging loss, so 90% of the energy drawn reaches the battery (illustrative)
• 26.32p/kWh standard home rate — Ofgem’s GB-average Direct Debit default-tariff rate from 1 October 2026
• 7p/kWh illustrative cheap overnight rate
• 80p/kWh illustrative public rapid rate

Putting 60kWh into the battery with a 10% charging loss takes about 66.7kWh from the charger. Here is what that charge costs at three rates:

Same car. Same battery. A more than tenfold difference in the price of one charge.

Cost per mile makes the comparison portable. Driving 100 miles at 3.5 miles per kWh uses about 28.6kWh in the battery, which draws about 31.7kWh from the charger with a 10% loss:

Those per-mile figures are what a charging mix turns into an annual bill. They are also the number to compare against petrol or diesel: at 35mpg and 145p per litre, a petrol car costs roughly 18.7p per mile in fuel alone.

Few drivers charge from one place at one price. A realistic year mixes cheap overnight charging at home, some charging at the standard rate, workplace charging, surplus solar and occasional public rapid charging. The blended price of that mix — weighted by how many kWh come from each source — sets your real running cost.

For example, a mix of 60% cheap overnight at 7p, 30% standard home rate at 26.32p and 10% public rapid at 80p blends to about 20.1p/kWh before losses — much closer to the standard rate than to the cheap headline rate.

Model how you actually charge, not the cheapest headline rate you could theoretically access.

Take the example car over 8,000 miles a year. At 3.5 miles per kWh with a 10% charging loss, that is about 2,540kWh drawn from chargers. The same miles can cost:

These are illustrative extremes, not forecasts. Most drivers sit between them, because real years combine several charging sources — which is exactly why the mix matters.

Free or discounted workplace charging belongs in your charging mix at its real price — often zero. Every mile charged free at work is a mile that costs nothing at home, no matter what your tariff says.

If a meaningful share of your miles can be charged at work for free, your blended charging cost can fall well below any home tariff. Model that share honestly: it is one of the biggest single levers in the whole calculation.

Both are cheap sources, but the right choice depends on what your surplus solar is worth elsewhere and what your cheapest import rate is. The rule is simple:

That rule turns into a clear recommendation for each common situation:

If you have a home battery, do not automatically send surplus solar to the car. Compare what the battery can replace later.

If the battery stores solar that would otherwise earn a 12p export, and it later avoids buying at 26p, that stored energy may be more valuable in the house than in the car. If the battery can instead fill itself overnight at 7p while your solar exports at 12p, the economics can flip — solar earns 12p, and the car charges from cheap grid energy.

The principle holds either way: put each kWh where it has the greatest value.

Take the 60kWh charge, about 66.7kWh with losses. Charging overnight at the illustrative 7p rate costs about £4.67. Using surplus solar that could otherwise earn a 12p export gives up about £8.00 of export income.

Overnight charging is about £3.33 better for that charge — because buying at 7p beats giving up 12p.

Change the export rate to 5p and the answer reverses: the solar is worth less than the overnight electricity costs, so using it for the car makes sense. The decision always follows the same comparison.

A bigger battery does not automatically cost more per mile. It holds more energy, but the running cost is driven by how far that energy takes you — efficiency, not capacity. An inefficient large-battery car can cost more per mile than an efficient smaller one.

Charging speed changes waiting time, not the energy itself. A faster charger does not inherently make the electricity more expensive to your car; the price you pay is set by the tariff or network behind it.

There is no single useful “full charge” answer. The honest number is your cost per mile, built from your mileage, your car’s efficiency, your charging locations and rates, and charging losses.

Work those four inputs through and the result is decisive: home charging on a cheap overnight rate is very hard to beat, workplace charging can be better still, and heavy public rapid charging is the expensive end of EV running costs.

Run your own numbers before drawing conclusions. Then the car decision becomes arithmetic you can defend, not a headline you have to trust.

The car sets the energy it needs. Your charging mix sets the price.