Taking a car on a ferry adds a layer of preparation that foot passengers skip entirely: documents specific to the vehicle, a few genuine safety rules around gas and alarms, and a boarding procedure that runs to its own timetable. None of it is complicated, but missing one item — a disarmed alarm, an undeclared gas bottle — can mean delay or refusal at check-in rather than a problem discovered mid-crossing.
Documents to have ready
Beyond your own passport or ID, have the vehicle's registration document, proof of insurance valid for the countries you're driving through, and your booking confirmation with the correct registration plate on it. If you're driving a hire car, check the hire agreement specifically permits the ferry crossing and the countries on the other side — some hire contracts restrict cross-border travel or require prior notice, and a ferry operator or border official finding this out at check-in is a bad time to discover a restriction. For EU or wider international travel, an international driving permit is sometimes required alongside your regular licence depending on your nationality and destination — check well ahead rather than assuming your home licence covers you everywhere.
Gas bottles and LPG systems
If your vehicle runs on LPG, or you're carrying a caravan or campervan with a gas bottle or a built-in gas system (cookers, fridges, heating), this must be declared at check-in and the gas supply is normally required to be switched off, with the bottle's isolation valve closed, before boarding. Some operators cap the number or size of gas bottles permitted, and rules differ enough between operators and routes that a quick check with your specific operator before travel avoids an awkward conversation at the port. Undeclared gas is treated as a genuine safety issue, not a formality — vehicles are sometimes refused boarding over it.
Vehicle alarms
Disarm your vehicle's alarm, or at minimum disable motion-sensor triggers, before boarding. Vehicle decks flex and vibrate during the crossing, particularly in rougher conditions, and a sensitive alarm can trigger repeatedly with no way for crew to identify or silence it once the deck is sealed and passengers move up to the accommodation areas — a genuinely disruptive problem on a crossing of several hours. Most operators mention this in booking confirmations or boarding instructions; take it seriously even if it feels like an unlikely scenario for your specific alarm.
What to check on the vehicle itself
- Fuel level — most operators ask you not to fill up to the brim and to keep the tank reasonably low as a fire-safety measure, rather than arriving completely full.
- No loose items on the dashboard, parcel shelf or elsewhere that could shift or fall during loading, unloading, or the crossing itself in rougher weather.
- Roof boxes, bike racks and any load beyond the vehicle's normal dimensions declared accurately at booking — see our guide to how to book a ferry with a car for how these affect your fare category.
- Tow bar-mounted accessories and trailers secured and measured as part of your total declared length.
Deck procedure: loading and unloading
At most ports, vehicles queue in marshalling lanes assigned by booking category well before boarding begins, and crew direct each vehicle onto the deck in a specific order — don't expect to choose your own position on the deck. See our guide to how ferry check-in works for the wider check-in process beyond just the vehicle marshalling lanes. Follow crew directions exactly during loading; deck space is tight and vehicles are often parked closer together than feels entirely comfortable, which is normal rather than a sign of an error. Once parked, apply the handbrake, leave the vehicle in gear (or "park" for automatics) as instructed, and take everything you'll need for the crossing with you, since most operators require passengers to leave the vehicle deck once loading is complete — you generally cannot return to your car mid-crossing except during specific, crew-announced comfort breaks on longer routes, and not at all on many shorter ones.
Unloading works in reverse: an announcement calls vehicle passengers back to the car deck ahead of arrival, and vehicles disembark in a sequence set by crew, typically starting with those parked to leave first based on how the deck was loaded. Have your keys, documents and boarding pass or vehicle ticket ready before the announcement, since the disembarkation window can move quickly once it starts.
Sleeping in your vehicle
On some routes and operators, campervans and motorhomes are permitted to remain on an open deck during an overnight crossing so passengers can sleep in the vehicle rather than booking a cabin — but this is not universal, is not available on enclosed decks for safety reasons, and needs confirming directly with the operator before you assume it. See our guide to how to book a ferry with a car for how to check this at booking stage, and our guide to foot passenger vs driving on a ferry if you're still deciding whether bringing a vehicle is worth it for your specific trip.
Pets travelling in the vehicle
Rules on leaving pets in the vehicle during the crossing vary considerably by operator and route — some permit it with the vehicle deck subject to periodic crew checks, others require pets to travel in a designated kennel area or be brought to pet-friendly cabins instead. This is worth confirming specifically when booking rather than assuming, particularly for longer crossings where welfare becomes a real concern. See our guide to pets on ferries in Europe for the ferry-specific rules and travelling with pets across borders for the wider document requirements. If your vehicle is a motorhome or camper rather than a standard car, our guide to motorhomes and campervans on ferries covers the extra considerations specific to those vehicles.
A final pre-boarding checklist
- Vehicle registration document, insurance and booking confirmation with the correct registration plate.
- Gas systems declared and switched off, bottle valves closed.
- Vehicle alarm disarmed or motion sensors disabled.
- Fuel tank not filled to the brim; loose items stowed.
- Everything you need for the crossing removed from the vehicle before it's parked on deck.
Frequently asked questions
Do I need to declare an LPG or gas system before boarding a car ferry?
Yes. Gas bottles and vehicle gas systems must be declared at check-in and are normally required to be switched off before boarding — this is treated as a genuine safety rule, and undeclared gas can mean a vehicle is refused boarding.
Should I disarm my car alarm before a ferry crossing?
Yes. Vehicle decks flex during the crossing and a sensitive alarm can trigger repeatedly with no way for crew to silence it once the deck is sealed, disrupting the crossing for other passengers.
Can I stay with my car during the crossing?
Generally no — most operators require passengers to leave the vehicle deck once loading is complete, except during specific crew-announced breaks on some longer routes. Take everything you need with you before leaving the vehicle.
Can I sleep in my campervan on the ferry instead of booking a cabin?
On some operators and routes, yes, usually only on an open deck, but this isn't universal — confirm directly with the operator when booking rather than assuming it's included or available on your specific sailing.
Sources and further reading:
- Vehicle deck and safety procedures: DFDS, Brittany Ferries, Stena Line, P&O Ferries operator websites.
- Gas and LPG carriage rules: individual operator conditions of carriage, confirmed directly before travel.
- Consumer passenger rights on sea crossings: European Commission (EU Regulation 1177/2010).