Petrol vs Electric Total Cost Calculator
Compare the true cost of ownership between petrol/diesel and electric vehicles over 5-10 years.
Petrol Vehicle
Electric Vehicle
Common Settings
Why the Sticker Price Is the Wrong Number to Compare
EVs cost more to buy than equivalent petrol cars, often £5,000 to £10,000 more new. People stop reading at this point and assume petrol is cheaper. The actual total cost of ownership over 5 to 7 years tells a different story. EVs cost roughly 3p to 5p per mile to run on home electricity vs 14p to 18p per mile for petrol; over 12,000 miles a year that is £1,200 to £1,500 saved annually on fuel alone. Servicing is also cheaper because EVs have no oil, no spark plugs, no exhaust system and significantly less brake wear (regenerative braking).
The calculator stacks all the costs side by side: purchase price, depreciation, fuel/electricity, insurance, road tax (VED), and maintenance. EVs typically pull ahead at year 4 to 6 of ownership for a typical driver doing 10,000+ miles per year. Below 8,000 miles a year, the petrol car often stays cheaper because there is not enough fuel saving to offset the higher purchase price.
Home Charging Is the Killer App
The whole 'EVs are cheaper to run' argument depends on home charging on an off-peak tariff. Octopus Go at 7.5p/kWh between midnight and 5am makes a 50 kWh full charge cost £3.75 and gives roughly 200 miles of range; that works out to under 2p per mile. Charging on a standard 28p/kWh tariff bumps that to about 7p per mile. Charging exclusively on public rapid chargers at 70p+ per kWh gets you to 18p per mile, which is no cheaper than petrol.
If you do not have driveway parking or a way to install a wallbox, the EV economic case is much weaker. Workplace charging or supermarket destination chargers help, but they are not always available and not always free. The [EV charging time calculator](/ev-charging-time-calculator) shows how charging speeds and costs vary across the home/workplace/rapid spectrum.
Depreciation Is Closer Than the Internet Says
EV depreciation has been a moving target. Tesla's repeated price cuts hammered the resale value of recent Model 3s and Model Ys; some early adopters lost £15,000+ on cars they bought new in 2022. But that is a Tesla-specific story, not an EV-wide one. Mid-2020s data shows mainstream EVs (Nissan Leaf, Hyundai Kona Electric, VW ID.3) depreciating at roughly the same 50 to 60% over 3 years as equivalent petrol cars.
Used EV demand is growing as more drivers consider them. Battery health is the main resale concern; cars with detailed service histories and a positive 'state of health' check (most are above 90% after 5 years) sell at a premium. Older Leafs (pre-2018) with smaller batteries hold value poorly because they are no longer practical for anything beyond local commuting. Recent models with 60+ kWh batteries are more like petrol cars in terms of resale risk.
VED, Insurance and the Hidden Costs
EVs paid no road tax (VED) until April 2025, when the Treasury closed the exemption. From April 2025, EVs registered after that date pay £10 first-year VED then £190/year from year 2 onwards. EVs registered before April 2025 are exempt up to 2025 then pay the standard £190 from 2026. Cars over £40,000 (which includes most new EVs) also pay an additional £410/year 'expensive car' supplement for years 2 to 6.
Insurance for EVs runs slightly higher than equivalent petrols, typically by 5 to 15%. The reason is repair cost: battery replacement costs and specialist body repair (because of the structural battery pack) push claim costs up. As more EVs hit the road and more body shops are EV-certified, this gap is narrowing year-on-year. Quote both options on comparison sites before buying; the actual gap on a like-for-like basis is often smaller than expected.
Worked Example: 5-Year Total Cost (12,000 miles/year)
| Cost | Petrol (£20k) | Electric (£35k) | EV Saving |
|---|---|---|---|
| Initial purchase | £20,000 | £35,000 | -£15,000 |
| Fuel/electricity (5yr) | £8,100 | £2,250 | +£5,850 |
| Insurance (5yr) | £2,500 | £2,750 | -£250 |
| VED (5yr) | £950 | £950 | £0 |
| Maintenance (5yr) | £4,800 | £2,400 | +£2,400 |
| Depreciation (50% / 45%) | £10,000 | £15,750 | -£5,750 |
| Total 5-year cost | £26,350 | £24,100 | +£2,250 |
Frequently Asked Questions
What's the breakeven mileage for an EV vs petrol?
Roughly 8,000 to 10,000 miles per year, with the breakeven hitting at around year 4 to 5 of ownership. Below that mileage, fuel savings do not accumulate fast enough to offset the higher purchase price within a typical ownership period. Above 15,000 miles per year, EVs pull ahead within 2 to 3 years, even on standard electricity tariffs. Company-car drivers with salary sacrifice schemes hit breakeven much faster because the BIK tax saving on EVs is enormous (2% in 2025/26 vs 25%+ for an equivalent petrol).
Will my electricity bill jump if I get an EV?
Yes, but less than you might fear. A typical UK home uses 2,700 kWh of electricity per year. Adding an EV doing 12,000 miles a year at 3.5 miles/kWh adds about 3,400 kWh, more than doubling household electricity usage. On a standard tariff that adds roughly £950 a year. On an off-peak EV tariff (Octopus Go at 7.5p/kWh for the EV portion), the same usage costs around £255. The cheap tariff is the entire reason EVs work financially; without it the maths is much closer.
How long do EV batteries last?
Most EV manufacturers warranty their batteries for 8 years or 100,000 miles to retain at least 70% of original capacity. Real-world data from Tesla, Nissan and Hyundai shows typical degradation of 1 to 2% per year, so a well-treated battery should retain 80%+ capacity at 10 years. Catastrophic failure is rare; the more common pattern is gradual range loss. Replacement battery cost has fallen sharply; in 2026 it is around £6,000 to £10,000 for most mainstream EVs, vs £15,000+ a few years ago.
What happens to old EV batteries?
Almost none go to landfill. Batteries that fall below 70% to 80% of original capacity get a second life as grid storage or domestic solar batteries; they still hold 70 to 80% of their original capacity, plenty for stationary applications. Beyond that, batteries are recycled for lithium, cobalt, nickel and copper, with recovery rates above 95% in modern recycling plants (Northvolt, Redwood Materials). The 'EV battery waste' crisis is largely a strawman; the industry has built recycling capacity ahead of the wave of end-of-life batteries.
Is a hybrid or plug-in hybrid cheaper than full EV?
Plug-in hybrids (PHEVs) are usually the most expensive option in pure cost terms because you pay for both a petrol engine and a battery system, and most drivers do not actually charge the battery often enough to capture the savings. Independent studies (DfT, ICCT) have shown real-world PHEV economy is typically 50% worse than the official figures because owners drive on petrol when the battery is flat. Full EVs are mathematically simpler: charge cheap, drive cheap, no fuel costs to forget about. Use the EV vs petrol calculator to model your specific use case.
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