Red Diesel Guidance • Updated September 2026
Red Diesel FAQs: UK Rules, Uses & Tax Explained
Clear answers to common questions about red diesel in the UK, including who can legally use it, current fuel duty and VAT, farming and construction rules, road use, generators, storage and the penalties for misuse.
Red diesel is still legal — but eligibility is restricted
Since April 2022, whether you can use red diesel depends on both the type of vehicle or machine and the purpose for which it is being used. The current red diesel fuel duty rate is 6.48p per litre.
View the full Red Diesel Law guide
Updated September 2026
Your Guide to Red Diesel Rules, Usage and Tax
Red diesel remains legal in the UK, but strict rules determine which vehicles, machines and activities are entitled to use it.
The regulations changed significantly on 1 April 2022, when many industries lost their previous entitlement to rebated diesel. Today, eligibility depends on both the type of machine involved and the purpose for which it is being used.
6.48p/litre
Current red diesel fuel duty as of 1 September 2026
52.95p/litre
Current main diesel fuel duty rate
Still legal
Red diesel remains available for qualifying uses
April 2022
Date the current restricted-entitlement regime began
Important
Red diesel eligibility can depend on the exact vehicle, machine and activity involved. This guide summarises current HMRC guidance but is not individual tax or legal advice. If you are unsure whether an application qualifies, check the latest HMRC guidance before using rebated fuel.
Red Diesel Basics
What is red diesel?
The essential facts about rebated diesel, why it is red and how it differs from standard road diesel.
What is red diesel?
Red diesel is diesel supplied at a reduced rate of fuel duty for qualifying uses.
It is also known as gas oil, rebated diesel, marked diesel or marked gas oil.
The fuel contains a visible red dye and chemical markers which allow HMRC to distinguish rebated fuel from fully duty-paid diesel.
The term “red diesel” primarily describes its tax and marking status. Red diesel supplied as gas oil commonly meets the BS 2869 Class A2 specification, while standard road diesel normally meets BS EN 590.
Is red diesel illegal in the UK?
No. Red diesel itself is not illegal.
It remains a legitimate fuel for vehicles, machinery and applications which qualify under current HMRC rules.
What changed on 1 April 2022 was the number of industries and activities entitled to use rebated fuel. Many former users — particularly within ordinary commercial construction — lost their general entitlement.
Can you still buy red diesel in 2026?
Yes. Red diesel remains available throughout the UK.
The important question is not whether you can physically purchase it, but whether the vehicle, machine or application in which it will be used is legally entitled to rebated fuel.
Eligible customers can continue to purchase bulk red diesel from authorised fuel suppliers such as Compass Fuels.
Do you need a licence to buy red diesel?
Most end users do not need a special personal licence simply to purchase red diesel.
However, suppliers of controlled oils have compliance and record-keeping obligations, and the purchaser remains responsible for ensuring the fuel is used only for an eligible purpose.
A supplier may therefore ask for information about your business, intended use or delivery location before supplying rebated fuel.
Why is red diesel coloured red?
The red colour exists primarily for tax enforcement.
Because red diesel benefits from reduced fuel duty, it contains visible dye and chemical fiscal markers which help HMRC identify whether rebated fuel has been used where it should not have been.
The colour does not mean the fuel is inherently lower quality.
What other names are used for red diesel?
Common terms include:
- Gas oil
- Rebated diesel
- Marked diesel
- Marked gas oil
- 35-second oil
In commercial discussions, “red diesel” and “gas oil” are often used interchangeably, although exact fuel specifications should always be checked.
What does BS 2869 Class A2 gas oil mean?
BS 2869 is a British Standard covering fuel oils used in engines and heating applications.
Class A2 gas oil is widely used in non-road diesel machinery and equipment.
It should not automatically be assumed to be technically identical to BS EN 590 road diesel. Always use a fuel grade approved by the equipment manufacturer.
Eligibility
Who can legally use red diesel?
Eligibility depends on both the machine and the activity for which it is being used.
Who can use red diesel in 2026?
Current qualifying uses can include certain activities connected with:
- Agriculture
- Horticulture
- Forestry
- Aquatic farming
- Arboriculture
- Rail transport
- Commercial marine transport
- Golf courses and driving ranges
- Registered Community Amateur Sports Clubs
- Travelling fairs and circuses
- Certain non-commercial heat and power generation
Being part of one of these sectors does not automatically make every machine or activity eligible.
Can farmers still use red diesel?
Yes. Agriculture remains one of the principal permitted uses of red diesel.
Qualifying agricultural vehicles and machinery may use rebated diesel for activities relating to agriculture, horticulture, aquatic farming and forestry.
This can include certain tractors, combine harvesters, crop sprayers, forage harvesters and other specialist agricultural machinery.
Can construction companies use red diesel?
For ordinary commercial construction work, generally no.
The construction industry's broad entitlement to use red diesel ended on 1 April 2022.
Excavators, dumpers and other plant are not automatically eligible simply because they operate off-road or on private land.
A machine may still qualify if it is being used for another independently permitted purpose, such as certain agricultural activities.
Can plant machinery use red diesel?
Not simply because it is described as “plant”.
Current HMRC rules look at the machine and the activity being carried out.
Operating off-road, remaining on private property or not being road-registered does not by itself establish entitlement to use red diesel.
Can generators run on red diesel?
Sometimes, but a generator does not automatically qualify simply because it is stationary.
Red diesel can be used for power generation in certain qualifying circumstances, including specified agricultural uses and electricity generation primarily for premises that are not used for commercial purposes.
An ordinary commercial generator supplying a construction site, warehouse, office, factory or data centre does not automatically qualify.
Can a boiler burn red diesel to heat a home?
Red diesel may be used for certain qualifying heating applications, including heat primarily generated for non-commercial premises, subject to HMRC's rules.
However, kerosene is the fuel more commonly used in UK domestic oil-fired heating systems.
The fuel must also be suitable for the particular boiler or heating equipment, so manufacturer guidance should be followed.
Can gardeners and landscapers use red diesel?
Certain genuine horticultural activities can qualify.
HMRC includes the cultivation and maintenance of gardens within horticulture, but this does not mean all general landscaping, grounds maintenance or work on private land automatically qualifies.
Eligibility should be checked against the precise activity being undertaken.
Can tree surgeons and arborists use red diesel?
Certain machinery used for arboriculture can qualify.
HMRC examples include machinery such as woodchippers, stump grinders, generators and mobile elevating work platforms when used for qualifying arboricultural activities.
Vehicle rules can differ from machinery rules, so not every vehicle associated with tree work is automatically eligible.
Can golf courses use red diesel?
Yes, for certain qualifying activities on existing golf courses and driving ranges.
This can include maintenance, repair and renovation of the existing facility.
Building an entirely new golf course, clubhouse or other new development does not automatically receive the same entitlement.
Can boats use red diesel?
Commercial boats and marine transport other than private pleasure craft can generally use red diesel.
Private pleasure craft are subject to different rules. In Great Britain, red diesel can still be purchased for pleasure craft, but the purchaser must declare the amount being used for propulsion and pay the appropriate full duty on that proportion.
Different rules apply in Northern Ireland.
Vehicles & Roads
Can red diesel be used on roads or in vehicles?
The rules are more nuanced than simply saying that red diesel can never appear in a vehicle travelling on a public road.
Can you drive on a public road using red diesel?
Red diesel cannot be used as ordinary road fuel in normal cars, vans, HGVs and road-going commercial vehicles.
However, some qualifying agricultural and other excepted vehicles may legally use red diesel while travelling on public roads for specified qualifying activities.
The rule is therefore not simply “red diesel is never legal on a public road”.
Can you use red diesel on private land?
Being on private land does not automatically make red diesel use legal.
Eligibility still depends on the vehicle or machine and the purpose for which it is being used.
An ordinary commercial business cannot use rebated fuel in otherwise ineligible machinery merely because the equipment never leaves privately owned property.
Can I run my car on red diesel if I only use it on a farm?
Not simply because the car is being driven on private farm land.
An ordinary car does not become an eligible agricultural vehicle merely because it is used on a farm.
If you are unsure whether a particular specialist vehicle qualifies, check the current HMRC definition of an excepted machine.
What should I do if red diesel is put in my road vehicle by mistake?
Do not deliberately continue using rebated fuel in a vehicle that is not entitled to it.
Keep evidence showing how the mistake occurred and consider having the tank and fuel system professionally drained or flushed before normal use continues.
Where there is any concern about duty liability or HMRC compliance, contact HMRC directly rather than relying on an assumption that dilution with white diesel will resolve the issue.
Can an HGV use red diesel?
Not for normal commercial haulage.
HGVs and ordinary road-going goods vehicles require fully duty-paid fuel.
Carrying agricultural produce, visiting farms, entering construction sites or spending time off-road does not by itself make an HGV eligible for red diesel.
Can tractors still use red diesel?
Yes, where the tractor qualifies as an agricultural vehicle and is being used for an eligible activity.
Qualifying activities include specified agricultural, horticultural, forestry and aquatic-farming work.
A tractor does not receive unrestricted red-diesel entitlement for every possible commercial use.
Can a tractor use red diesel while gritting public roads?
Qualifying agricultural vehicles can use red diesel for certain activities connected with dealing with frost, ice, snow and flooding.
The vehicle must still satisfy the relevant HMRC vehicle and usage rules.
Can red diesel and white diesel be kept in separate tanks on a tractor?
Dual-fuel arrangements need to be considered carefully.
A second tank must not be used as a method of switching the propulsion engine between rebated and fully duty-paid fuel simply according to whether the operator believes the current journey qualifies.
Different rules can apply where separate fuel supplies power genuinely separate engines or machinery.
Because these arrangements can be technically specific, check the exact configuration against HMRC guidance before operating a dual-fuel system.
Tax, Duty & Price
How is red diesel taxed?
Red diesel is not tax-free. Its principal financial advantage is the lower rate of fuel duty applied to qualifying use.
Red Diesel Duty
6.48p/litre
Current rate at 1 September 2026
White Diesel Duty
52.95p/litre
Current main diesel rate
What is the current tax on red diesel?
As of 1 September 2026, the fuel-duty rate on marked gas oil is 6.48p per litre.
The equivalent main diesel rate is 52.95p per litre.
The current difference in fuel duty is therefore 46.47p per litre.
Did red diesel duty increase on 1 September 2026?
No.
An increase had previously been scheduled for 1 September 2026, but the government cancelled it.
Red diesel remains at the temporary 6.48p-per-litre rate and the main diesel rate remains 52.95p per litre under the current arrangements through 31 December 2026.
Is red diesel tax free?
No.
Red diesel is rebated, not tax free.
Fuel duty is still charged, although at a much lower rate than ordinary road diesel. VAT is also charged at the appropriate rate for the particular supply.
Is red diesel always charged at 5% VAT?
No.
The VAT treatment depends on the quantity supplied and the nature and purpose of the supply.
Certain qualifying supplies, including supplies falling within HMRC's small-quantity rules, can attract the reduced 5% rate.
Larger ordinary commercial supplies that do not meet a qualifying condition are generally standard-rated at 20%.
Why is red diesel cheaper than white diesel?
The biggest structural reason is fuel duty.
At current rates, red diesel carries 6.48p per litre of duty compared with 52.95p per litre on standard diesel.
The final delivered price also depends on wholesale fuel markets, oil prices, exchange rates, supply conditions, delivery location and order volume.
How much does red diesel cost?
There is no single UK red diesel price that applies to every customer.
Prices can move throughout the week and vary according to:
- Wholesale gas oil prices
- Order volume
- Delivery postcode
- Local availability
- Delivery urgency
- Wider oil-market conditions
For a current delivered price, request a quotation using your delivery postcode and required volume.
Storage & Handling
How should red diesel be stored and managed?
Good fuel management becomes especially important where a site uses both rebated and fully duty-paid diesel.
What are the rules for storing red diesel on a farm?
Red diesel should be stored in suitable fuel-storage equipment and in accordance with the environmental and safety requirements applying to the location.
Good practice includes:
- Using a suitable, secure fuel tank
- Checking tanks and pipework regularly
- Protecting fuel from water and contamination
- Monitoring for leaks
- Keeping dispensing equipment secure
- Maintaining appropriate fuel records
- Clearly identifying red and white diesel systems
Can you mix red diesel and white diesel?
Physically the fuels can mix, but the legal issue is whether the machine is entitled to contain rebated fuel.
Adding white diesel to a tank containing red diesel does not make the rebated fuel legally disappear.
If the machine is being moved to non-qualifying work, HMRC rules concerning residual rebated fuel need to be followed.
Can a machine switch from red diesel to white diesel?
Yes.
Where a machine moves from qualifying to non-qualifying use, the operator must ensure that rebated fuel is no longer being used illegally.
Depending on the circumstances, the fuel system may need to be drained or flushed. Businesses whose machinery regularly switches between qualifying and non-qualifying activities may choose to use fully duty-paid diesel throughout.
How long does red diesel remain detectable?
There is no reliable fixed period after which red diesel should be assumed to be undetectable.
It contains visible dye and chemical markers specifically designed to allow HMRC to identify rebated fuel.
Compliance decisions should therefore never be based on the assumption that red diesel will become undetectable after a certain number of days or after being diluted.
Can the red dye be removed from red diesel?
You must not attempt to remove, alter or conceal the markers used to identify rebated fuel.
Interfering with fuel markers or adding substances intended to prevent their identification can lead to HMRC enforcement action.
Removing the visible colour would not legitimately convert rebated fuel into duty-paid white diesel.
Can you buy red diesel in barrels or drums?
Yes. Red diesel can be supplied in suitable drums or other approved containers as well as by bulk tanker delivery.
For businesses using larger quantities, bulk delivery will normally be more practical and cost-effective.
Regardless of how the fuel is supplied, the purchaser must still be entitled to use rebated diesel.
What should I do with unwanted or surplus red diesel?
Do not dispose of diesel into drains, soil or water and do not transfer it into machinery that is not legally entitled to use it.
Surplus or contaminated fuel should be handled by an appropriate fuel-recovery or waste-management provider.
Where usable fuel is being transferred between tanks or sites, make sure the receiving application is entitled to use red diesel and that appropriate records are retained.
Does red diesel go off?
Like other stored diesel fuels, red diesel can deteriorate over time.
Storage life depends on factors such as tank condition, moisture, microbial contamination, temperature and how frequently the fuel is turned over.
Fuel held for long periods — particularly for standby equipment — should be inspected and tested where operational reliability is critical.
Compliance
HMRC checks and penalties
Red diesel contains fiscal markers specifically so that illegal use can be identified and investigated.
Can HMRC test the fuel in a vehicle or machine?
Yes.
HMRC officers have powers to inspect and sample fuel from vehicles, machinery, vessels, appliances and storage tanks.
Owners and operators may also be required to provide access to fuel systems and relevant records.
Red diesel contains chemical markers in addition to visible dye, allowing rebated fuel to be identified even where its appearance has changed.
What are the penalties for using red diesel illegally?
HMRC has substantial enforcement powers where rebated fuel is used without entitlement.
Action can include:
- Seizure of the vehicle, vessel, machine or appliance
- Seizure of fuel and associated equipment
- Recovery of unpaid fuel duty
- Financial wrongdoing penalties
- Criminal prosecution in serious cases
HMRC can seek unpaid duty relating to previous illegal use, potentially covering several years.
Serious offences can result in an unlimited fine, imprisonment or both.
What fuel should I use if I am not sure I qualify?
Do not rely on the fact that red diesel may historically have been used within your industry.
Instead ask:
- What type of vehicle or machine is being used?
- What activity is it being used for?
- Does that combination qualify under current HMRC rules?
If you do not qualify for rebated fuel, fully duty-paid white diesel may be appropriate.
Businesses looking for a renewable alternative can also consider HVO fuel , subject to equipment-manufacturer approval.
Can HVO also be supplied as a rebated fuel?
Potentially, yes.
HMRC allows HVO to receive rebated treatment for the same qualifying uses as diesel where the relevant requirements concerning eligibility, supply and fuel marking are met.
Fully duty-paid HVO is also available for commercial applications where rebated fuel is not permitted.
Official red diesel guidance
Red diesel legislation and fuel-duty rates can change. We recommend checking current government guidance where eligibility or taxation is material to your decision.
Need red diesel delivered?
Compass Fuels supplies BS 2869 Class A2 red diesel to eligible customers throughout the UK, with bulk deliveries from 500 litres through to 36,000+ litres.
If you are unsure whether your application qualifies for rebated fuel, check the latest HMRC guidance before ordering.