What Car? Q&A - Is supermarket petrol different?

Q: Is it true that the fuel sold at supermarket petrol stations is not of the same quality as that as you would buy from a dedicated petrol station?
Alex Wells

A: According to the Petrol Retailers Association, there is no difference between the standard petrol you buy from supermarkets or franchised petrol stations. In most cases the petrol and diesel is even produced at the same refinery and delivered in the same trucks.

The exception to this is specialist fuels, such as Shell’s Optimax and BP’s Ultimate. In their case, the fuel is enhanced with additives, which produce that brand’s particular properties.