What is heating oil?

Around 1.5 million households in the UK are not connected to the national gas grid and use heating oil to heat their homes. 

The key difference between gas from the grid and heating oil (as well as liquefied petroleum gas or LPG) is that heating oil is delivered by road and stored in a tank. If your home has an oil boiler, it runs on heating oil. 

Here are the most reliable oil boilers based on ratings from owners and heating engineers.

What type of home heating oil do I need?

Two types of oil are used for domestic heating:

• Kerosene heating oil – also known as 28-second or heating oil. It's the most common type used in UK homes and lighter and cleaner than gas heating oil.
• Gas heating oil – also known as 35-second oil or red diesel. It's usually used in older boilers, agriculture or commercially. 

If you've just moved into a property with an oil boiler, the type of heating oil you will need is determined by the type of heating system that's already installed there.

If your boiler or tank isn't labelled clearly, ask the previous owner what type they used, but if they're unsure or can't help, reach out to a technician registered with Oftec (the Oil Fire Technical Association) to find out.

Should you be able to choose which type of heating oil to use, kerosene is the most efficient. In cold weather it's unlikely to ‘wax up’ (form crystals that stop it from flowing as easily) until it reaches around -39°C. But do check with the supplier regarding this, as it can vary. 

See more tips on maintaining and fixing heating oil problems. 

Should I buy premium kerosene heating oil?

You can buy a premium type of kerosene that contains additives. These additives allow it to burn more cleanly, and therefore more efficiently. 

Premium kerosene usually costs around £20 to £30 more than standard kerosene (based on 500 litres). 

For certain oil-fuelled appliances, such as Agas, you may have to use particular extra additives as well. If you're unsure if this applies to your appliance, check with the manufacturer to find out whether this is required. Additives cost around £15 for a bottle to treat 1,000 litres of heating oil. 

How much does heating oil cost?

The price of heating oil fluctuates. It rose from a low of 25p per litre in July 2020 to 99p per litre in July 2022. 

Since then, the price has dropped to around 70p per litre. But this is still much higher than the steadier prices seen in 2018 and 2019, when a litre cost between 45p and 55p per litre.*

Is heating oil cheaper than gas?

No, heating oil actually tends to be pricier than heating your home through gas. This is because heating oil is less efficient than gas as a fuel and more expensive to purchase per unit.

However recent gas price rises have brought the unit costs closer together. 

Find out what affects the price of heating oil and how to get the best deal in best heating oil prices. 

*Average prices for a litre of kerosene from Sutherland Tables, which collects domestic fuel pricing data from across the UK for each quarter of the year.