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Should I buy a petrol or a diesel car?

I do about 100 to 120 miles per week combination of motorway and city. Should I buy a petrol or a diesel car?

Asked on 17 September 2025 by Ben Baki

Answered by Matt Robinson
If you're clocking a lot of miles, diesel does still make sense, but on a more modest figure like 100 miles per week petrol is the way to go. If you're buying something relatively recent, the gap in terms of fuel economy between the two might be less than you expect.

Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG

Our Fuel Cost Calculator shows you which will be the best choice for you.

Compare the running costs of petrol, diesel and electric cars to make the right choice for you.

Petrol or diesel ... or even electric?
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