EV vs Petrol Cost Calculator

Compare yearly fuel costs of an electric car with a petrol or diesel car.

p/litre
miles/kWh
p/kWh

Your result

Yearly saving with EV£560.04
Petrol per year£1,131.47
EV per year£571.43

Updates as you type. Based on 2025/26 UK figures where relevant.

How this is worked out

Petrol cost uses miles ÷ MPG × 4.546 × price per litre. EV cost uses miles ÷ miles per kWh × price per kWh.

Tips

  • UK MPG uses imperial gallons (4.546 litres), which differ from US gallons.
  • HMRC's approved mileage rate is 45p per mile for the first 10,000 business miles.
  • Home EV charging on an off-peak tariff is usually far cheaper than public rapid chargers.

Frequently asked questions

How does the eV vs Petrol Cost Calculator work?

Petrol cost uses miles ÷ MPG × 4.546 × price per litre. EV cost uses miles ÷ miles per kWh × price per kWh.

What MPG should I use?

Use your real-world figure from your car's trip computer if you can; official figures are often optimistic.

Can I claim for commuting miles?

No. Normal commuting to a permanent workplace doesn't count as business mileage.

How often do HMRC mileage rates change?

Rarely. The 45p rate has been unchanged for many years, but always check GOV.UK.

This calculator gives an estimate for general information. It isn't financial, tax, legal or medical advice. Check official figures on GOV.UK or NHS.uk, or speak to a qualified adviser.