There is a particular shade of pink that makes British sailors nervous in French marinas, and it is the colour of the diesel in their own fuel tank. I have watched people lie awake over it. The honest answer is more relaxed than the marina-bar rumours suggest, but there are two or three lines you genuinely must not cross, and the penalties for crossing them are no joke. Here is how it actually works for a visiting boat.
Quick definitions, because the words get muddled
Red diesel is UK rebated marine diesel, dyed red, on which a reduced fuel duty has been paid. In France the equivalent dyed off-road fuel is GNR (gazole non routier), and there is also fioul domestique for heating. The dye is a marker for tax authorities, not a different fuel chemically. The whole argument is about which duty has been paid, and where.
The good news: red diesel in your tank is fine
If you arrive in France with red diesel in your boat's fixed fuel tank, bought legally in the UK with the appropriate duty paid, you are not committing an offence. The French position, confirmed by experienced cruisers and customs guidance over many seasons, is that you have already paid fuel tax on it in your home country, so they are not going to treat the contents of your built-in tank as smuggled goods, even though the dye and the duty rate differ from theirs.
The key word is "fixed". The dispensation applies to fuel in the boat's permanent tank. Keep your UK fuel receipts. If a douane officer asks, the receipt showing you bought it duty-paid in Britain is the document that ends the conversation. No receipt, and you are relying purely on goodwill. The fuel question is part of the wider arrival routine, and what you tell the douanes is covered in clearing customs when you arrive in France by boat.
The line you must not cross: jerrycans
Here is the hard rule. Carrying red diesel in jerrycans is not allowed. The dispensation covers the fixed tank only. Portable cans of dyed fuel are treated as a different thing entirely, and that is where visiting boats get into real trouble. If you are topping up jerry cans of red diesel to carry as deck cargo, stop.
When you buy fuel in France, buy white road diesel for any portable cans, keep the receipt, and you have a clean story. The few extra euros per fill is trivial against the alternative.
It is worth remembering why this distinction exists. The fixed tank is part of the boat, and the dispensation is really about not penalising a visitor for the fuel that happened to be aboard when they crossed the border. A jerrycan is portable, separable, and from a customs point of view indistinguishable from someone trafficking cheap fuel. That is the logic, and once you see it the rule stops feeling arbitrary. The moment dyed fuel can be lifted off the boat and poured into a car, the French take an interest.
Why the penalties are genuinely serious
French customs treat fuel-duty evasion as fraud, not a parking ticket. The headline penalties for serious fuel offences in France run to very large fines, up to three years in prison in the worst cases, and confiscation of the vehicle or vessel. You will almost certainly never see the prison end of that as a visiting yachtsman with a tank of legitimately bought UK red, but the framework explains why the douanes can be firm, and why "I didn't realise" carries no weight. The system is built for catching road users running their cars on cheap dyed fuel, and a boat that plays by the spirit of the rules stays well clear of it.
Buying fuel in France
Most seagoing boats in France fill up with ordinary white road diesel at the marina fuel berth or a nearby station, full duty paid, no drama. The French standard rate of VAT, 20%, is baked into that pump price along with the fuel excise. There is no general "duty-free fuel for yachts" scheme for private pleasure craft on the coast, so do not arrive expecting a tax-free bunkering deal. What you pay at the pump is what it costs.
The fuel berth itself is a small skill of its own, and prices vary a lot between marinas and fuel stations ashore. I put together a rundown of where and how to fill up in boat fuel in France and where to bunker, which is worth a look before you cut it fine on the gauge in an unfamiliar port.
The canal exception: GNR for inland boats
The picture changes if you leave the sea and head into the French canals. GNR, the French red off-road fuel, can legally be used by inland navigation boats and certain river pleasure craft. So a barge or a canal cruiser pottering through the Canal du Midi or the Bourgogne can buy and burn GNR, which is taxed at a lower rate than road diesel. Since July 2024 the GNR taxation rules were reformed, with a reduced excise rate applying under certain conditions, so the exact figures shift, but the principle holds: inland craft have access to the cheaper dyed fuel that seagoing vessels do not.
This matters if your plan is to cross France by canal from the Channel to the Med, or to spend a season on the inland waterways. You move from the coastal rule (white diesel, full duty) to the inland rule (GNR available) the moment your boat becomes an inland craft for the trip. If the canals are on your itinerary, the broader inland picture, including the VNF vignette you also need, is covered in the overview of French waterways diesel, water and pump-out.
A note for non-UK visitors
Dutch, German, Belgian and Scandinavian boats arriving with their own home-bought marine fuel are in the same broad position as the Brits: fuel legitimately bought and duty-paid in your own country, sitting in the fixed tank, is not contraband. The dye colour and the duty rate differ country to country, but the receipt is what matters. Keep proof of where and how you bought it, never decant dyed fuel into portable cans, and you are fine.
The simple visiting-boat rulebook
Strip it all back and it comes down to five lines:
- Red diesel in your fixed tank, bought duty-paid at home, is fine in France. Keep the receipt.
- Red or dyed diesel in jerrycans is not. Buy white road diesel for cans in France.
- There is no duty-free fuel scheme for private seagoing pleasure craft on the French coast.
- Inland canal boats can legally use the cheaper French GNR, seagoing boats cannot.
- French customs treat fuel fraud as a criminal matter, so stay on the right side of these lines and you have nothing to fear.
I have bunkered up and down both coasts of France for years on a tank that still has the last of its UK red in the bottom of it, kept my receipts in the same plastic folder as everything else, and never had so much as a raised eyebrow. Play it straight and the pink diesel is the least of your worries.
