Driver tools Petrol and diesel fuel costs
Petrol or diesel?
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|Example running costs comparing a petrol with a diesel car|
|Example number||Car price difference||Annual fuel cost petrol||Annual fuel cost diesel||Annual CO2 emissions petrol||Annual CO2 emissions diesel||No. of years to recoup diesel price premium|
Choosing between a petrol and a diesel car can be difficult. While you can be fairly confident the petrol model will be cheaper to buy, knowing which is going to cost you more in the long run is a bit more difficult.
This is because the overall running costs of petrol and diesel cars are affected by so many factors, including fuel prices, servicing bills and emissions-based charges.
We have our own fuel efficiency test to give more realistic mpg figures - these are available in all our car reviews
The calculator on the right only takes initial purchase price, fuel costs and mileage into account, but should give you an idea of how many years’ driving it will take to make buying a diesel the most cost-effective choice - if indeed the diesel will ever be cheaper.
The 'diesel payback' period could take much longer than you would think - especially for lower mileage drivers. However, if the diesel car saves you money on car tax and depreciation, it may pay for itself sooner.