Red diesel (gas oil)

Like many forms of fuel, red diesel is derived from crude oil that has been extracted from the ground. The crude oil is heated and distilled to become gas oil, and red dye is added to the final product to give it its distinct colour and make it easily recognisable against colourless road diesel. The red dye alerts HMRC inspectors to any misuse of the rebated fuel. 

Red diesel fuel is the same as white diesel fuel; the only difference is that it contains a red dye to identify illegal usage. Red diesel is cheaper than white diesel due to lower fuel tax duty as it is heavily rebated. Due to duty equalisation, red diesel is no longer subsidised for all uses, including construction and most commercial applications. For more information on who can use red diesel and what for, read our blog on the red diesel duty changes. 

No, red and white diesel must not be mixed. For those who use both red and white diesel – such as farmers – supplies must be kept separate, and machinery tanks and supply lines must be flushed in-between permitted and non-permitted uses in order to remain compliant.  

Certain vehicles, such as diggers, may use red diesel in permitted settings for permitted uses. 

For example, a digger can use red diesel if it is for an application on agricultural land and is an accepted agricultural activity. However, a digger on a construction site would not be permitted to be powered by red diesel, as this is a non-permitted, commercial activity.  

At Budget 2020, the government announced that it was removing entitlement to use red diesel from most sectors from 1 April 2022. Duty equalisation was introduced as part of the government’s move to drive forward the net zero carbon 2050 agenda. 

Removing most red diesel entitlements was intended to incentivise users of polluting fuels like diesel to improve the energy efficiency of their vehicles and machinery, invest in cleaner alternatives, or use less fuel. If you would like to kick-start your energy transition today, explore your options in our alternative fuels guide. 

The price of red diesel changes daily due to influences from the global oil market. Prices can also depend on quantity and location, so the price of red diesel really depends on the order being placed and what’s currently happening in the market.  

Certas Energy is proud to be a competitive red diesel supplier and strive to offer customers a great red diesel price. Find out today’s red diesel prices by speaking to a member of our friendly team on 0345 600 4040 or request a quote online and your local team will come back to you. 

Yes, farmers can still use red diesel. For the most part, the agricultural industry is unaffected by red diesel duty equalisation and farmers can carry on using tractor diesel in much the same ways as before. However, accepted use of red diesel in agriculture has become more restricted and there are exceptions. Check out our blog on what farmers need to know about red diesel duty equalisation. 

Red diesel can be used for non-commercial heating but can no longer be used by industries as a heating oil or for power generation in a commercial setting. 

However, cost-effective alternative heating solutions are available, including industrial heating oil/Therma35 and kerosene. 

Yes there are alternatives to red diesel that are readily-available. As well as standard white diesel/DERV, there are cleaner diesel alternatives that are becoming increasingly available, including OEM approved fuel, GTL Fuel (Gas-to-Liquid), and renewable diesel Hydrotreated Vegetable Oil (HVO), (dependent on usage, duty may still apply). Both fuels can help lower emissions and accelerate businesses’ net zero ambitions. 

Yes, red diesel storage is subject to regulations. However, these vary across different regions and are dependent on type and use of tank. It is recommended to check with local councils for specific guidance. 

In England, if more than 200 litres are stored, Control of Pollution (Oil Storage) (England) Regulations 2001 must be adhered to. To comply, the fuel dispensing hose must be within a locked cabinet and any drips contained within the bund. Further information on oil tank regulations can be found in our guide. 

It is important to note that there are different rules for agriculture where fuel is used specifically for agricultural purposes, such as powering a tractor or grain dryer. Check out our blog for more information on storing fuel safely on farms.  

Failure to adhere to the oil tank regulations can result in considerable fines or even prosecution. 

Certas Energy tank specialists are available to provide product and installation guidance. We also offer a full range of fully compliant fuel storage tanks. To learn more about our range or to speak to one of our specialists today, click here.  

No, you don’t need a licence to purchase red diesel but you must be an eligible user and sign an RDCO form upon purchase. You must only buy red diesel from a company who is HMRC registered.  

To determine if you are a permitted user, see our red diesel duty FAQs blog. 

Yes, red diesel does expire but can last around 12 months if stored correctly. 

To maximise shelf life, keep it in a dry, cool environment and use fuel additives to prevent bacterial growth, water contamination, and build-up. For guidance on the right additives to use, speak to one our specialists.  

The rate you pay can depend on the quantities purchased and uses. To apply to reclaim fuel tax, you can fill in the HO27 form. 

HMRC and police authorities can spot check for red diesel by dip testing fuel tanks. If there is red dye present, it stains the dipstick, identifying the fuel as red diesel. Using red diesel outside of the regulations is subject to significant fines, seizure of vehicles and even prosecution. 

Want to ensure you are complying with the red diesel rules? Download our handy compliance checklist.