Explore the key differences between red diesel (gas oil) and white diesel (DERV).
If you need diesel fuel for your business, this guide breaks down the key differences between white diesel and red diesel, including the costs and requirements of each fuel so that you can choose the right product for your business with confidence.
White diesel, which is also referred to as standard diesel or DERV, is the most commonly used fuel in the UK. It can used for a range of applications which include powering passenger cars, commercial fleets, machinery, generators, industrial sites and more.
Red diesel, which is also referred to as gas oil, is chemically the same as white diesel, the only difference between the two fuels is that red diesel is marked with a red dye which differentiates the fuel for tax purposes.
While both fuels are chemically identical and can work in the same engines, fuel systems and generators, there are important differences which you should be aware of before using using them with your equipment.
Red diesel differences:
White diesel differences:
We have further broken down and compared all of the key features of both diesel fuels in the table below.
| Feature | Red diesel | White diesel |
| Other names | Gas oil, marked diesel, 35 sec oil, cherry red | Standard diesel, DERV, road diesel, forecourt diesel |
| Taxation and cost | Low tax, rebated fuel | Fully taxed fuel |
| Performance | Identical | Identical |
| Legal requirements | Restricted | Unrestricted |
| Road legal | No | Yes |
| Common use cases | Agriculture, rail transport, community sports clubs, travelling fairs | Road fleets, commercial site, generators |
| Availability | Less availability due to suppliers requiring to be monitored under the Registered Dealers in Controlled Oil (RDCO) scheme | Widely available |
White diesel
There are no restrictions in the UK for any sector that wishes to use white diesel, providing that the fuel is being stored and handled safely and in accordance with environmental regulations.
Red diesel
The majority of UK businesses are not permitted to use red diesel. Legal use of red diesel is now restricted to the following sectors and purposes (since April 2022):
The right diesel for your business depends on your sector and the intended application of the fuel. If you’re eligible to use red diesel, you can reduce fuelling costs. When using diesel on-road, or in any other application where red diesel is prohibited, you must use white diesel to abide by the law.
There is no maximum fine for anyone caught using red diesel illegally. Consequences and penalties include:
HMRC detect illegal usage by conducting unannounced fuel checks regularly and through investigation of reported suspects.
Understanding the rules and confirming that red diesel is permitted for your intended purpose is the most important step to safeguard your business. This involves reviewing regulations and your operations to ensure that your red diesel usage is compliant in your use case – consider all of the applications you need the fuel for before placing an order.
If organisations use a mix of diesel and red diesel, you must ensure the fuels are always kept in separate containers and that tanks and hoses are clearly labelled to prevent any cross over.
Keeping records will help you demonstrate to HMRC that you are compliant with red diesel regulations. Records you should hold include:
If you’re switching between fuels, ensure that all red diesel is removed before fuelling with white diesel. Red dye traces and stains can remain in fuel systems and engines after it has been removed which is why it requires careful planning to ensure that no traces remain.
Make staff aware of all red diesel regulations to ensure they handle and use red diesel appropriately. This involves giving clear instructions for refuelling and placing orders.
Suppliers of red diesel must be approved under the RDCO. As a registered supplier, we can help you navigate the legal landscape and check your eligibility based on your sector and intended application.
If you’re concerned about red diesel compliance, complete our RDCO form and call our team on 0330 678 0880 for support.
Red diesel was introduced in the UK to distinguish rebated fuel from fully taxed fuel (white diesel). By adding a red dye, it became easier for authorities to identify whether fuel was being used in accordance with regulations and to detect misuse. Fuel was already taxed differently based on the application before red diesel was introduced, the red dye simply makes it easier to enforce the law.
While both fuels are chemically the same, you should not mix the fuels unless you are switching to red diesel permanently. Using different fuels in the same systems will show if you are inspected by HMRC because traces of red dye will be present in fuel systems, even if it is not currently being used. Below is a breakdown of the switching process for each scenario.
Switching from red diesel to white diesel:
Switching to white diesel from red diesel requires careful consideration. To ensure that no red dye is found after your switch you must:
Switching from white diesel to red diesel:
Switching from white diesel to red diesel is only permitted if you are repurposing your equipment for an eligible use of red diesel. If you switch to red diesel and are not eligible to use it, you are breaking the law. There is no need to modify your fuel systems before switching but you must update labels and train staff to ensure that there is no misuse.
White diesel has more availability throughout the UK than red diesel as it can be purchased at most forecourts in small quantities. The availability of red diesel at forecourts is extremely limited and only found in rural areas or dockyards where there is more demand.
If you need to get either fuel delivered to your site, there are a number of suppliers throughout the UK. There are more suppliers of white diesel than red diesel due to there being less demand for red diesel and the fact that it requires more work to distribute and document.
To ensure operational continuity, you must choose an agile supplier who can match the demands of your business.
At Nationwide Fuels, we can supply both white and red diesel to sites across the UK within 24-48 hours as standard. We have a robust network of depots and vast fuel reserves which enable us to provide total supply security, giving you peace of mind and that your business will not suffer from fuel shortages.
Whether you need a small or large amount of fuel, we can meet your requirements with quantities available from 205 – 36,000+ litres.
To place an order, or to learn more about red and white diesel, call 0330 678 0880 today.
