Does fuel go off?

Regardless of how well they are stored, all types of fuel will ‘go off’ eventually – though shelf life varies from fuel to fuel, and is highly dependent on the conditions in which it is stored.

Diesel has a shelf life of between 3 and 12 months depending on the storage method, and type of additives used. Should it be exposed to water, diesel is highly likely to suffer from microbial growth and contamination, worsening the quality significantly. After the 12 month mark, diesel tends to thicken and can block filters, causing issues in all applications.

Petrol – whilst less commonly stored in large tanks, has an average life expectancy of around six months. Heat exposure can be extremely detrimental to this fuel.

The typical lifespan of heating oil, on the other hand, is between 18 and 24 months, meaning, when stored in a well-maintained tank, one batch of oil may be used to heat your home for two winter periods.