Should I buy a petrol, diesel, hybrid or electric used car?

It comes down to how far you drive and where. There is no universally best choice, and the honest answer for most buyers is that annual mileage decides it.

• Petrol — best for lower mileage and mostly urban or mixed driving. Cheaper to buy than an equivalent diesel, simpler exhaust systems, and no particulate filter concerns from short trips.
• Diesel — still makes sense above roughly 12,000 miles a year with a lot of motorway work, where the fuel economy earns back the higher purchase price. Avoid if your driving is mainly short urban journeys, as the particulate filter needs longer runs to regenerate.
• Hybrid — strong in stop-start traffic, where the electric motor does most of the low-speed work. Self-charging hybrids need no plug. Plug-in hybrids only make financial sense if you will actually charge them regularly.
• Electric — cheapest per mile to run and exempt from the ULEZ charge, best if you can charge at home. Public charging is considerably more expensive than home charging, which changes the sums.

On used electric cars specifically, battery health matters more than mileage. Ask for a state-of-health figure where available, and remember most manufacturers provide a separate battery warranty, typically around eight years, which may still have time left to run.

One point often missed: from April 2025 electric cars pay vehicle excise duty in the UK, so the tax advantage is smaller than it once was, though running costs remain lower.