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Costs and money , Buying a used car , Electric and hybrid · Updated 2026-10-18

Fuel or electricity: how to compare running costs

People often ask whether an electric car is cheaper to run than a petrol or diesel one. The honest answer is that it depends on your prices, your driving and where you charge. Instead of repeating general claims, this guide shows you how to do the comparison yourself, with your own numbers. It takes ten minutes and gives a result you can trust more than any headline.

Start with cost per kilometre

To compare different kinds of energy, convert everything into the same unit: the cost of driving one kilometre, or 100 kilometres. For a fuel car you need two numbers: how much fuel the car uses per 100 km, and the price of a litre. Multiply them and divide as needed. For an electric car you need how much electricity it uses per 100 km, and the price of a kilowatt-hour. The same multiplication gives the cost.

Use real consumption, not the figure in the brochure. Real consumption is usually higher than the official one, for both types of car. Your own trip computer over a few months is the best source. If you do not have one yet, owner reports and tests for the specific model are a reasonable starting point, but treat them as a range.

The price of electricity is not one price

This is where electric cars differ most from fuel cars. Fuel has a pump price that anyone can see. Electricity can cost very different amounts depending on where you charge.

• Home charging usually uses your household tariff and is often the cheapest option, if you can charge at home or at work.
• Public slow and fast chargers usually cost more per kilowatt-hour, and fast chargers are often the most expensive.
• Mixed use is what most people actually do. Work out your own share of each.

Read charging explained for how the different charging types work. If you cannot charge at home, your costs will be higher, and the comparison may look very different.

Include losses

Not all the electricity that leaves the socket ends up in the battery. Some is lost as heat during charging. When you compare costs, use the consumption measured at the plug if you can, or add a small allowance for losses. Cold weather also raises consumption, as described in EV winter range.

Look at more than energy

Energy is only one part of the cost of owning a car. A fair comparison should include the rest.

• Purchase price and depreciation. Electric and fuel cars can differ in price and in how fast they lose value. Check the local market data and ask what similar used cars sell for, not only what they are advertised for.
• Servicing. Electric cars have fewer moving parts to service, but they still need tyres, brakes, fluids and checks. Fuel cars have more routine items, such as oil, filters and belts.
• Tyres. Heavy cars and strong torque can wear tyres faster. This is true of some electric cars.
• Insurance and taxes. These can differ between types of car and between countries. Rules differ by country, so check with the competent authority.
• Charging equipment. A home charger has a one-time cost, which you should spread over the years you expect to use it.

Our cost of ownership tool helps you put all of these in one yearly figure. For background on the less visible items, see the real cost of owning a car.

Hybrids sit in between

Hybrids use both fuel and electricity, and the mix depends on the type and on how you drive. A plug-in hybrid can be very cheap to run if you charge it often and mostly drive short trips, and costly if you rarely plug it in. See hybrid types explained to understand the differences.

How your driving changes the result

• Short city trips favour electric cars, because they are efficient at low speeds and do not waste energy while stopped.
• Long motorway trips reduce the advantage, because consumption rises with speed and public fast charging is dearer than home charging.
• High yearly distance makes the cost per kilometre more important. Low yearly distance makes the purchase price and fixed costs matter more.

Use the trip cost calculator to see what a typical journey costs in each case.

A worked method

1. Write down your yearly distance and your typical trip length.
2. Find the real consumption for each car you are comparing.
3. Find your actual price per litre and per kilowatt-hour, including your charging mix.
4. Multiply to get the cost per 100 km and per year.
5. Add servicing, tyres, insurance, taxes and depreciation.
6. Compare the totals over the years you plan to keep the car.

If you are deciding between types, our EV, hybrid or petrol guide looks at the wider picture beyond cost.

What to remember

• Compare cost per 100 km using your own prices and real consumption.
• Electricity has many prices; where you charge decides the result.
• Include purchase, depreciation, servicing, tyres, insurance and taxes.
• Your driving pattern can reverse the answer.
• Check the current local rules and prices instead of relying on general claims.

Charging Costs Diesel Electric Fuel Hybrid Petrol