Buying Guide · 6 min read
Petrol, Diesel, Hybrid or Electric: Which Used Car Should You Buy?
There's no single right answer to the fuel question — only the right answer for your driving. The same car that saves one driver £1,500 a year costs another driver money. Here's the honest version of the comparison, based on what we see across thousands of customer conversations.
Petrol: the safe default
For most drivers doing average mileage — school runs, commutes under an hour, weekend trips — a used petrol car remains the simplest choice. Purchase prices are sensible, any garage can service one, and modern petrol engines are clean enough that almost everything from 2006 onwards is ULEZ compliant.
The trade-off is fuel economy on long runs: if you do serious motorway miles, petrol costs more per mile than diesel or a good hybrid.
Diesel: still right for high-mileage drivers
Diesel's reputation has taken a battering, but the engineering case hasn't changed: 15,000+ miles a year, mostly motorway, and a modern Euro 6 diesel is still the cheapest way to travel. Strong torque also makes diesels the right tool for towing.
Two cautions. First, ULEZ: only diesels from roughly September 2015 onwards comply — check every car. Second, short trips: diesel particulate filters (DPFs) need regular sustained runs to regenerate, so a diesel used only for town driving will eventually have expensive DPF trouble. If your driving is local, don't buy a diesel.
Hybrid: town economy without the plug
Self-charging hybrids (think Toyota Yaris, Corolla, C-HR) are at their best exactly where diesels are at their worst: stop-start urban driving, where the electric motor does the heavy lifting and fuel economy in the 50s and 60s mpg is realistic. They're also famously reliable — the hybrid systems in used Toyotas routinely outlast the rest of the car.
Plug-in hybrids (PHEVs) offer 20–40 miles of electric range — brilliant if you can charge at home and your commute is short, close to pointless if you can't, because you're carrying a heavy battery you never use.
Electric: cheapest to run, but do the maths
A used EV charged at home overnight costs a fraction of petrol per mile, servicing is minimal, and ULEZ is never a question. For a predictable daily pattern with home charging, the running-cost case is unanswerable.
Be realistic about three things: real-world range (winter cuts quoted figures noticeably), your charging situation (public-only charging erodes most of the savings), and battery health on older examples — ask for a battery health report or check the car's indicated range against its original spec.
The quick decision guide
Match the fuel to the mileage and you won't go far wrong:
- Under 8,000 mostly local miles a year → petrol or self-charging hybrid.
- Town and city driving, lots of stop-start → hybrid first, petrol second; avoid diesel.
- 15,000+ motorway miles a year → Euro 6 diesel still wins on cost per mile.
- Home charging available and regular routes → seriously consider an EV.
- Driving into London regularly → whatever you pick, verify ULEZ compliance first.
We stock all four — petrol, diesel, hybrid and electric — and we'll give you the same straight answer in person: which car in our showroom actually suits your miles, not whichever one we'd rather sell. Tell us your driving and we'll narrow it down.