Electric vs Petrol Cost Calculator
Compare the real-world running costs of an electric vehicle against a petrol car. Factor in home and public charging costs, fuel prices, your mileage, and the EV purchase premium to see which makes financial sense.
UK average is roughly 7,400 miles per year.
Check current prices near you.
Most EV owners charge 70-90% at home where electricity is cheapest.
How much more the EV costs to buy. Set to 0 for running costs only.
How It Works
The calculator estimates annual energy costs for both an EV and a petrol car based on your mileage. For the EV, it blends home and public charging costs according to your charging split. For petrol, it uses your MPG and the current pump price. It then calculates how long it would take to recoup the higher purchase price of an EV through lower running costs.
Key Factors That Affect the Result
- Home charging is key — charging at home on a standard tariff costs roughly 24-25p per kWh, while public rapid chargers can cost 60-79p per kWh. The more you charge at home, the cheaper your EV running costs.
- Annual mileage matters — higher-mileage drivers recoup the EV premium faster because the per-mile saving compounds. At under 5,000 miles a year, the payback period can be very long.
- Electricity tariffs vary — EV-specific tariffs (like Octopus Go, Intelligent Octopus) offer off-peak rates as low as 7-12p per kWh, which dramatically reduces EV running costs.
- Petrol prices fluctuate — use our comparison tool to check current prices in your area.
Beyond Fuel Costs
This calculator compares fuel/energy costs only. EVs also benefit from:
- Zero road tax (VED) — currently free for EVs, saving £180+ per year vs most petrol cars
- Congestion charge exemption — London ULEZ and congestion zone savings
- Lower maintenance — no oil changes, fewer brake replacements (due to regenerative braking), fewer moving parts
- Lower CO₂ emissions — even on the UK grid, EVs produce significantly less CO₂ per mile than petrol cars
For more on fuel costs, read our guide to saving money on fuel, or use our fuel savings calculator to compare different petrol forecourts.