An overnight ferry is one of the more civilised ways to travel. You eat something, you sleep, and you wake up in a different country instead of a motorway service station. But the crossing only feels restful if you have packed for it. Board the ship with the wrong bag and you will spend the night hunting for a charger, shivering in a bunk, or realising your passport is locked in the boot of a car you cannot reach until morning.

What follows is the packing list I have refined over too many night crossings: what to carry on, what to leave behind, and what to sort out before you join the queue at the port.

Documents first, comfort second

Everything that proves who you are and what you have booked should travel in one bag you keep with you, never in the car. Ferry operators can and do ask for identification at check-in, and the rules differ by route. A domestic crossing may only need a booking reference; an international one will normally want a passport or national identity card for every passenger, including children and infants.

Keep these together in a single wallet or plastic folder:

• Passports or ID cards for every traveller, plus birth or consent documentation if you are travelling with a child and not both parents
• Your booking reference and boarding pass, printed or saved offline on your phone
• Vehicle registration, driving licence and motor insurance details
• Pet paperwork if an animal is travelling, and any vaccination records
• Travel insurance policy number and the emergency contact number for your operator

Save a screenshot of the booking and a photo of each document in your phone's camera roll. Signal at sea is patchy, and a screenshot works when a website will not.

Pack a cabin bag you can actually carry

On most ships you park, walk up a steep staircase or ramp, and do not see your car again until the announcement on arrival. So the bag you take to the cabin has to contain everything you need for the night. A soft holdall or rucksack is far easier to manage in a narrow corridor than a wheeled suitcase.

Cabin temperature is the thing people most often get wrong. Ship air conditioning can be fierce, and a thin cotton T-shirt will not cut it at 3am. Bring layers you can add and remove rather than one heavy jumper.

Comfort items worth the space

• A warm mid-layer, thick socks and something soft for your feet
• Earplugs and an eye mask — engine noise and corridor lights are part of the experience
• A small torch or a phone with a dimmed screen, for finding the bathroom without waking everyone
• Toiletries in a leak-proof bag; check whether towels and soap are provided in your cabin grade
• Any medication you take regularly, in your hand luggage rather than the boot
• A power bank and a short extension lead, since sockets are often in awkward corners
• Something to read that does not need a signal

If you are prone to motion sickness, speak to a pharmacist before you travel about what suits you, and follow the instructions on timing. Taking tablets once the ship is already moving is usually too late.

What to leave in the car

The car deck is closed to passengers for the crossing, so treat the vehicle as a locked storage unit you will not visit. Suitcases, spare shoes, beach gear and the bulk of your holiday luggage can all stay in the boot. Keep the boot tidy and, if you are driving through the night before boarding, make sure nothing valuable is on display — port car parks and decks are busy places.

Two exceptions. Take a jacket in with you even on a warm evening; the deck can be cold and windy when you step out for air. And take the car keys, because you may need them at the other end while everyone else is still collecting their bags.

Food, drink and the small hours

Most overnight ferries have a restaurant, a café and a bar, and many serve food late. But there is usually a dead zone between about midnight and the breakfast service, and that is precisely when hunger strikes in a bunk.

Pack snacks that are quiet, tidy and do not fill the cabin with smell: nuts, oatcakes, fruit, a wrapped sandwich from home, a few biscuits. Avoid anything strongly spiced or pungent. Bring a refillable water bottle and fill it before you sail, or from a tap in a public washroom if the cabin has none.

Check your operator's rules on bringing your own alcohol on board, as several restrict it to the bars and restaurants. If you like a hot drink before bed, a travel kettle is rarely permitted, so a flask filled at the café is the reliable option.

Travelling with children, pets or a nervous passenger

For children, the priorities are sleep and distraction: a familiar comforter, headphones, a spare set of clothes for the small one who spills juice at 11pm, and a snack they can reach without waking the whole cabin. Bunk beds often have no rail on the upper berth, so decide who sleeps where before lights out.

Pet rules vary widely. Some operators require dogs to stay in the vehicle, others provide kennels, and a growing number offer pet-friendly cabins. Confirm the arrangement when you book rather than at the port, and pack a lead, water bowl and something absorbent for the journey. Take advice from your vet if your animal is anxious about travel.

The night-before routine

Pack the cabin bag first and the car second, so you are not digging through a packed boot at the terminal. Charge every device, download your entertainment, fill the water bottle and put the document wallet by the front door. Eat a proper meal before boarding rather than queueing for a late one, and go to bed early if you can — the wake-up call on an overnight ferry tends to come sooner than you expect.

A grab-and-go checklist

If you remember nothing else, remember this short version. Documents on your person. Layers, socks, earplugs, eye mask and toiletries in a soft bag. Medication, charger, power bank and snacks. Keys in your pocket. Everything else stays in the car.

Do that, and the crossing becomes what it should be: a quiet night's sleep between two days of driving.

Photo: moinzon / Pixabay