Help with red diesel
A plain-English guide to what red diesel is, who can legally use it under the tightened 2022 HMRC rules, and how to source it for your business.
What is red diesel?
Red diesel — also called gas oil, 35-second oil or rebated diesel — is chemically identical to standard road diesel (DERV). The only difference is a red dye and chemical markers added at the terminal so HMRC can identify it during roadside checks.
Because it's taxed at a much lower rate, red diesel is significantly cheaper. In return, it's restricted by law to a narrow set of off-road uses. Putting red diesel in an on-road vehicle — even a van you also use on a building site — is a criminal offence.
Who can legally use red diesel?
In April 2022 HMRC removed entitlement from most sectors. These are the main categories that still qualify today.
Agriculture & forestry
Tractors, combines, telehandlers and other off-road farm machinery — the largest legitimate use case for red diesel.
Commercial marine
Vessels operating in UK coastal and inland waters, including fishing boats and harbour craft.
Rail transport
Diesel locomotives on non-electrified routes plus track maintenance equipment.
Non-commercial heating
Heating fuel for non-commercial premises like schools, hospitals, places of worship and rural homes off the gas grid.
Travelling fairs & circuses
Generators and rides for genuine travelling shows — one of the niche categories preserved in 2022.
Sailing, golf & amateur sport
Equipment used by registered amateur sports clubs, sailing clubs and similar non-commercial bodies.
Construction, manufacturing, mining, road maintenance, plant hire and most commercial heating lost entitlement in 2022 — those sectors must now use white diesel or HVO.
DERV vs red diesel
The key differences at a glance.
Why it isn't worth the risk
- HMRC can dip your tank at any time and test for the red marker.
- Vehicle and fuel can be seized on the spot — including hire and finance vehicles.
- Restoration fees plus back-duty owed on every litre used illegally.
- Fines can run into thousands per offence and may include prosecution for repeat misuse.
Sourcing red diesel
Red diesel is sold in bulk by tanker delivery to your tank or bowser. Prices move daily with global oil markets, but order volume, delivery location and urgency all swing the per-litre rate.
Major UK suppliers include Certas Energy, Crown Oil, WCF, Watson Fuels and Rix — all offer same/next-day delivery to most postcodes.
- Bigger orders (1,000L+) almost always unlock a better pence-per-litre rate.
- A regular standing-order delivery beats ad-hoc spot prices.
- Compare 2–3 suppliers — local depots often undercut national list prices.
- Keep proof of off-road use and HMRC-compliant invoices for your records.
- Consider HVO as a drop-in low-carbon alternative where eligible.
Need help arranging red diesel?
Tell us about your operation and we'll point you to a compliant supplier with the best rates for your area and volume.
Independent guide. Fuel Vertu is not affiliated with Certas Energy or HMRC.