RealCost Guide
Cost of Charging vs Petrol UK
Charging an electric car can be much cheaper than petrol, but only if the electricity price is sensible. Home charging, workplace charging and public rapid charging can give very different answers.
Use this page to compare EV charging cost against petrol cost, understand when an electric car saves money, and avoid assuming every EV is automatically cheaper to run.
Charging is not one fixed price
The biggest mistake is comparing petrol against one electric price. Home charging can be cheap, but public rapid charging can be far more expensive.
Run separate estimates for home charging, workplace charging and public charging if you use more than one charging method.
Compare electric charging vs petrol running cost
Use the calculator to compare petrol cost against EV charging cost using mileage, petrol MPG, fuel price, EV efficiency and electricity price.
For a detailed EV-only charging estimate, use the EV Charging Cost Calculator as well.
Quick answer: EV charging is usually cheapest when you can charge mostly at home or on a low-cost tariff. Petrol can look more competitive if you rely heavily on expensive public rapid chargers, drive low mileage, or the EV has higher insurance, tyre or depreciation costs.
What decides charging vs petrol cost?
The answer depends on energy price, efficiency and how many miles you drive.
This is the EV equivalent of fuel price. Home and public prices can be very different.
Higher petrol prices make EV charging savings more noticeable.
A more efficient EV goes further for each unit of electricity.
A petrol car with poor MPG becomes much more expensive at higher mileage.
The more you drive, the more small per-mile differences matter.
Mostly home charging is very different from mostly public rapid charging.
Example charging vs petrol comparison
These examples are illustrative. Use your own prices and efficiency for a better estimate.
Home-charged EV
At 30p per kWh and 3.5 miles per kWh, charging costs about 8.6p per mile.
Petrol car
At £1.50 per litre and 45 MPG, petrol costs about 15.2p per mile.
Public-charged EV
At 80p per kWh and 3.5 miles per kWh, charging costs about 22.9p per mile.
RealCost warning: the same EV can look cheap on home charging and expensive on public rapid charging. Your charging access matters as much as the car itself.
When charging is likely to beat petrol
EV running costs are strongest when electricity is cheap and mileage is regular.
You can charge at home
Home charging usually gives the strongest EV running-cost advantage.
You drive enough miles
Higher mileage gives more opportunity for lower charging cost per mile to add up.
The EV is efficient
An efficient EV with good miles per kWh makes each unit of electricity go further.
When petrol can still be cheaper overall
A cheaper energy cost does not always mean a cheaper car.
You rely on public rapid charging
Expensive public charging can reduce or remove the EV running-cost advantage.
You drive low mileage
Low mileage gives less opportunity to recover higher purchase price, insurance or depreciation costs.
The EV costs more elsewhere
Insurance, tyres, finance, depreciation or purchase price can outweigh charging savings.
Home charging vs public charging
This is the biggest split in the charging vs petrol decision.
Mostly home charging
Usually the strongest case for EV savings, especially if you can use cheaper overnight electricity.
Mixed charging
Use a realistic average electricity price or run separate home and public estimates.
Mostly public rapid charging
This can make EV running costs much closer to petrol, especially on longer journeys.
How to compare charging and petrol properly
Do not use best-case numbers for one car and worst-case numbers for the other.
Charging cost is not the full EV cost
A fair EV vs petrol comparison needs more than energy cost.
Insurance
Some EVs can be more expensive to insure, so check quotes before buying.
Tyres and repairs
Weight, tyre size and repair complexity can affect the real ownership cost.
Depreciation
A cheaper charging cost can be wiped out by higher value loss or buying the wrong used EV.
How this page is different from related calculators
Use the right page for the question you are answering.
Explains when EV charging beats petrol and when it may not.
Direct tool for comparing petrol and electric running cost.
EV-only charging cost using kWh price, battery size, efficiency and losses.
Useful calculators and guides
Use these next to check the full decision, not just the headline energy cost.
Compare costs →
Calculate charging →
Check petrol cost →
Check full cost →
Read guide →
Compare options →