Most rules get broken not out of defiance but out of ignorance, and French boating rules are broken more than most because the people breaking them are visitors who simply assumed the home-water way of doing things travelled with them. It does not. After a few seasons of comparing notes on pontoons from Calais to Cannes, the same handful of mistakes come up again and again. Here they are, roughly in order of how often I see them, with the actual penalties attached.
1. Overstaying the 90 days
The most common and most expensive habit, particularly among the British since Brexit. The rule is 90 days in any rolling 180 across the Schengen area, and as of 12 October 2025 your entries and exits are logged biometrically by the EU Entry/Exit System, fully operational from 10 April 2026. The old game of vague stamps is over.
Overstay and French law sets the standard fine at 198 euros, double the 99-euro cost of a long-stay visa. Worse cases of illegal stay can draw up to 3,750 euros, and an overstay can trigger an entry ban of one to five years across the whole Schengen zone. The ban is the real sting, because it can wreck the following season entirely. I broke the counting down in detail in the Schengen 90/180 day rule for boaters, and the wider catalogue of Brexit boat mistakes British sailors still make covers the traps around it.
2. Sailing without compliant Division 240 kit
France sets its own safety-equipment standard, Division 240, and it applies in French waters regardless of your flag. The required kit steps up by distance from a shelter: more is demanded beyond 6 miles, including a fixed VHF, and more again offshore.
Visitors routinely arrive with a kit list built for home regulations and assume it covers them. If the Gendarmerie Maritime or the affaires maritimes board you and the equipment is missing or non-compliant, you face a fourth-class fine, an obligation to put it right, and in the worst case the boat can be detained. The fix is cheap and the inspection is real, so it is a poor corner to cut.
3. Using VHF without the right licence
Carrying a radio is not the same as being licensed to use it. Your set needs a valid MMSI, and France, along with Germany, the Netherlands and Belgium, expects ATIS capability in VHF transmissions. Domestically a permit may suffice, but for international waters an operator certificate such as the CRR is required.
A fixed VHF also becomes mandatory beyond 6 miles from a shelter under the safety rules, so the boat that planned to coast-hop without one is offside the moment it heads offshore. The licensing is inexpensive but slow to arrange, which is why so many people are technically transmitting without proper authority. It is worth being precise here, because the two halves are separate: the station licence and MMSI cover the equipment, while the operator certificate covers the person at the microphone. Plenty of boats have a correctly registered radio and nobody aboard qualified to operate it internationally, or the reverse. Both need to be in order, and an officer who asks will know the difference.
4. Treating the boat's VAT status as somebody else's problem
This one is quiet until it is loud. A boat in EU waters needs a provable VAT position, and for non-EU-flagged vessels the alternative is the temporary admission relief, which allows use for up to 18 months in a two-year period without becoming liable for VAT. Stay beyond that without dealing with it and the boat can become liable for import VAT on its value.
Visitors break this by losing track of dates or by never carrying proof of status at all. Keep the evidence aboard. My guide to the VAT status of a boat in EU waters sets out what actually counts as proof, and it is the document a customs officer will ask for first.
5. Skipping the arrival declaration
Arriving from outside the Schengen area, you are expected to file an entry-and-exit border declaration. France does not require the yellow Q flag unless you have something to declare, which lulls people into thinking arrival is informal. It is not. Slipping in unannounced and being noticed turns a routine formality into an awkward conversation with customs.
The declaration takes minutes if you have crew details ready, which is the whole argument for keeping a proper boat paperwork checklist for a season in France within arm's reach of the chart table.
6. Carrying the wrong papers, or none
The Gendarmerie Maritime can and does ask to see the boat's documents. Registration, evidence of insurance, the radio licence, your competence certificate, the VAT or temporary-admission proof. Visitors break this not by lacking the documents but by leaving them at home, scanned to a phone that has no signal, or buried in a locker.
The fines here are situational rather than fixed, but the time cost of sorting it out at the dock is guaranteed. Third-party liability insurance is also effectively required to take a berth, so an uninsured boat is breaking a rule the marina will enforce even if the state does not.
7. Anchoring where you must not
Down on the Mediterranean coast, the seagrass meadows of posidonia are protected, and anchoring over them is increasingly restricted with real enforcement and fines on larger vessels. Visitors who anchor by eye, dropping on the nearest patch of "sand" that turns out to be weed, are squarely in the firing line. Check the local rules and the no-anchor zones before you let the chain run. The enforcement is no longer theoretical: along the Cote d'Azur and the Var, dedicated zones now ban anchoring over posidonia meadows for vessels above set lengths, and the patrols that check are real. The honest mistake of dropping on weed is treated the same as a deliberate one.
8. Forgetting the boat tax deadline
This one only bites French-flagged boats, but plenty of visitors buy and register locally without realising they have taken on an annual duty. The francisation and navigation duty (still widely called the DAFN) falls due by 31 March each year for an owner who held the boat on 1 January, with a 5% surcharge for late payment. The duty applies once the hull reaches 7 metres, or below that with an engine of at least 22 administrative horsepower, and the rates start gently, with engines up to 5 horsepower exempt. The amount is small; the surcharge and the chasing letters are the avoidable part.
The pattern under all of it
Notice what these have in common. None of them is hard to comply with. Every one is broken because a visitor carried a home-water assumption across the Channel or the border and never checked whether it still held. The kit, the licence, the count, the declaration: all known in advance, all sortable from a desk over winter.
The fines, taken individually, are not ruinous. A few hundred euros here, a detention there. The expensive one is the Schengen ban, which costs you a season rather than a sum. It is also worth knowing who actually checks. On the water it is most often the Gendarmerie Maritime or the affaires maritimes, who can stop you, board you and inspect documents and safety kit. In the marina the capitainerie enforces the insurance and berthing rules. At the border the customs and police side handles the immigration declaration and, increasingly, the biometric record. They do not all want the same paper, which is why a single tidy folder beats trying to remember which document satisfies which uniform. Hand over what is asked, calmly, and most checks are over in minutes.
The cheap insurance against all of it is an afternoon spent reading the actual French rules before you cast off, instead of finding out which one you broke when someone in uniform steps aboard.
