Your neighbour’s electric car costs them pennies to run. Your brother-in-law insists EVs are a con and his diesel does 60mpg. The adverts promise savings, the sceptics promise regret, and you’re stuck in the middle trying to make the biggest vehicle decision of the decade. Petrol or electric? The answer is genuinely “it depends” — but on specific, calculable factors, not vibes.

This guide gives you a decision framework based on real numbers: purchase costs, running costs, your driving patterns, and the practical realities of charging — so you can decide with a spreadsheet instead of an argument.

The Purchase Price Gap (and How Fast It’s Closing)

Electric cars still cost more upfront — typically £5,000–£10,000 more than equivalent petrol models, though the gap narrows yearly and used EVs are now genuine bargains (depreciation has been steep, which punishes new buyers and rewards used ones). But purchase price is only the entry fee. The decision lives in total cost of ownership: purchase price minus resale value, plus fuel/energy, servicing, insurance, and tax over your ownership period.

Worked example: a £28,000 petrol car versus a £35,000 electric equivalent, kept five years and 50,000 miles. The EV saves roughly £4,000–£6,000 in fuel (electricity at home rates versus petrol), £1,000–£1,500 in servicing (fewer moving parts, no oil changes, regenerative braking sparing the pads), and several hundred in VED differences. Resale values are the wild card — but even conservatively, the EV often wins on total cost for average-mileage drivers. Low-mileage drivers (under 6,000 miles/year) may find petrol cheaper overall, because the fuel savings never repay the purchase premium.

Your Driving Pattern Decides More Than Anything

Electric wins clearly if: you drive 8,000+ miles/year, most journeys are under 150 miles, you can charge at home overnight (this is the big one — home charging at ~25p/kWh versus public rapid charging at 70p+/kWh transforms the economics), and you have a driveway or dedicated parking. Petrol still wins if: you can’t charge at home (relying on public charging erodes most of the fuel saving), you regularly drive 250+ miles in a day, you need maximum flexibility for unpredictable long trips, or your annual mileage is low.

The honest middle: hybrids suit drivers who want lower running costs without charging logistics — and our guide to home EV charging covers the installation costs, grants and tariffs that make or break the electric case. Your household energy setup matters too — an EV on an off-peak tariff is dramatically cheaper to run than one charged at peak rates.

The Practical Realities Nobody Puts in Adverts

Range in winter: expect 20–30% less range in cold weather — a 250-mile EV becomes a 180-mile EV in January. Fine for most use, worth knowing before a winter motorway trip. Charging time: home overnight charging is effortless; public rapid charging takes 20–40 minutes for a meaningful charge — plan it around coffee, not as a petrol-station equivalent. Insurance: EVs currently cost more to insure (expensive battery repairs, specialist parts), though the gap is narrowing. Servicing: genuinely cheaper — no oil, fewer brakes, fewer things to break — but tyre wear is higher (weight and torque), so budget for that.

The 2035 factor: the UK’s phase-out date for new petrol and diesel car sales means the market, infrastructure and resale values all tilt electric over time. Buying petrol today isn’t foolish — but buying petrol in 2029 with a five-year ownership plan deserves harder thought, because you’ll be selling into a market that’s moved on.

A Decision Worksheet

Answer these five questions honestly: 1) Can I charge at home? (No = strong petrol lean.) 2) What’s my annual mileage? (Under 6,000 = petrol lean; over 10,000 = electric lean.) 3) How often do I drive 200+ miles in a day? (Monthly+ = petrol/hybrid lean.) 4) How long will I keep the car? (5+ years = electric’s savings compound.) 5) What’s the used market offering? (A two-year-old EV at 60% of new price often beats both new options.) Score yourself: 4–5 electric-leaning answers means the EV almost certainly wins on total cost; 4–5 petrol-leaning means it doesn’t — yet.

The Used Market: Where the Smart Money Goes

The most interesting petrol-vs-electric battle isn’t new — it’s used. Two-to-three-year-old EVs have depreciated hard (fleet returns flooded the market), creating genuine bargains: £35,000-new EVs selling at £18,000–£22,000 with most of their battery warranty remaining. At those prices, the total-cost maths transforms — the purchase premium shrinks while the running-cost advantage stays, making used EVs the best value in motoring for eligible drivers.

Buying used electric? Check battery health via the car’s own diagnostics or a specialist report (most EVs show battery state-of-health in menus or apps), verify the charging cable and type (CCS is the current rapid-charging standard), and confirm which software updates have been applied. Buying used petrol? The usual checks apply — service history, MOT record, cambelt status — plus a realistic view of how long you’ll keep it given the 2035 phase-out. Either way, the used market rewards the patient: set up alerts, wait for the right example, and let someone else pay the depreciation.

One more consideration: salary sacrifice schemes (where your employer leases you an EV from pre-tax salary) can make new EVs cheaper monthly than used petrol cars — if your employer offers one, run those numbers before dismissing new electric as unaffordable. The government’s clean vehicle information sets out current grants and tax treatment.

Conclusion

Petrol versus electric isn’t a moral choice or a technology bet — it’s arithmetic applied to your life. High-mileage drivers with home charging save thousands going electric; low-mileage drivers without home charging usually don’t. Run your own numbers on total five-year cost, be honest about your driving patterns, and check the used market before buying new. The right answer is the one your spreadsheet gives you, not the one the loudest voice in the pub insists on. Two questions, honest answers, and the decision makes itself. Study Zapmap’s live charging map for your regular routes — the reality of local infrastructure should shape the decision as much as the maths.

Frequently Asked Questions

Are electric cars really cheaper to run?

Per mile, yes — typically 3–5p/mile on home charging versus 12–18p/mile for petrol. But the purchase premium means total-cost victory depends on mileage: high-mileage drivers win big, low-mileage drivers may not break even.

How long do EV batteries last?

Modern EV batteries typically retain 80%+ capacity after 8–10 years/100,000+ miles, and most carry 8-year warranties. Battery degradation is real but slower than early fears suggested; catastrophic failure is rare.

Can I run an EV without home charging?

Yes, but the economics weaken significantly — public charging costs 2–3x home rates, and the convenience factor drops. It’s workable with nearby reliable chargers and a routine built around them, but it’s the single biggest predictor of EV satisfaction.

Should I wait for better/cheaper EVs?

Technology improves steadily, but waiting has a cost too — every year of waiting is a year of petrol bills. If the numbers work now, buy now; the “perfect” EV is always 18 months away, permanently.

What about hybrids as a middle ground?

Self-charging hybrids suit drivers who want lower fuel bills without charging logistics — no plug needed, 50–65mpg in town driving. They’re the rational compromise for urban drivers without home charging, though they can’t match a home-charged EV’s running costs.