Taking a ferry to France is one of the most civilised ways to start a holiday. You drive on, eat a slightly underwhelming breakfast, and step off in Normandy or the Pas-de-Calais a few hours later. It is also surprisingly easy to get the details wrong: a route that adds three hours of driving, a check-in time you misread, a dog without the right paperwork. None of these mistakes are hard to avoid once you know where they hide. Here are the seven that catch people out most often, and how to sidestep each one.

1. Booking a route that looks cheap and turns out to be expensive

Ferry pricing rewards flexibility, which is why so many drivers book Dover–Calais on autopilot. If you are heading to the Loire or Brittany, that crossing leaves you with a long, toll-heavy slog through northern France. Portsmouth–Caen or Portsmouth–Le Havre can cost more up front while saving a tank of fuel, a couple of hours behind the wheel and a great deal of motorway fatigue. The same logic applies elsewhere: Newhaven–Dieppe is quieter than you might expect and drops you a comfortable drive from Rouen.

What to compare before you book

• Total driving time from your door to your first night's stop, not just the crossing length
• Toll costs on French autoroutes, which add up quickly on a long transfer
• Whether an overnight sailing with a cabin suits you better than a dawn start
• Port departure times that fit your household — a 6am sailing means a 3am alarm and tired children
• Whether the arrival port is somewhere you would happily spend a night if plans slip

2. Cutting the check-in window too fine

Most operators ask car passengers to check in at least an hour before departure on short crossings, and 90 minutes or more on longer ones. That is the start of the window, not a target to aim for. Factor in passport control, summer Saturday traffic, roadworks and the occasional motorway closure, and it becomes clear why so many people watch their sailing leave without them.

Set your alarm for the check-in time rather than the departure time, and treat the operator's stated minimum as a deadline for leaving the house, not for arriving at the barrier. Foot passengers usually have a shorter window, but queues at the terminal still exist. If you do miss a sailing, you will often be moved to a later one for a fee, subject to space — and on a busy August weekend, space is exactly what there isn't.

3. Booking details that don't match your documents

Small discrepancies cause real delays at the port. Names should match passports exactly, including middle names if the operator asks for them. Add every passenger, including infants, and check your vehicle registration carefully — a zero typed as the letter O is a genuine problem at the barrier.

Vehicle details matter too. If you booked a standard car and later fitted a roof box, a bike rack or a tow bar, tell the operator before you travel: height and length affect where you are parked and what you are charged. Passport rules are worth checking properly rather than assuming. For British travellers heading to the EU, a passport generally needs to have been issued less than ten years before the date of entry and to be valid for at least three months beyond your planned return, and there are limits on how long you can stay. Requirements do change, so confirm with the official government guidance and the ferry operator, and take professional advice if your circumstances are unusual — dual nationality, visas, or non-UK passports, for example.

4. Packing the car so the crossing works against you

The classic mistake: everything you need for the next twelve hours is at the bottom of the boot, under the buggy and the tent. Car decks are closed while the ship is at sea, so there is no popping back for a jumper or a phone charger. Pack a small crossing bag that stays with you, containing entertainment for the children, any medication, a spare layer, snacks and a change of clothes if you are travelling with a baby.

Keep valuables with you rather than in the car. If you are prone to seasickness, choose a seat low down and mid-ship, spend time in the fresh air, and eat something plain rather than a full fried breakfast. If you use travel sickness tablets, take them before you sail; they work far better as prevention than as a cure. Ask a pharmacist if you are unsure what suits you. Finally, check the current rules on taking meat, dairy or plant products into the EU before you load the cool box.

5. Leaving pet paperwork and pet spaces too late

Travelling with a dog or cat needs planning, not optimism. Pets generally need a microchip, a valid rabies vaccination and an animal health certificate issued shortly before travel, and dogs returning to Great Britain from France usually need tapeworm treatment within a set window before arrival. Rules are updated from time to time, so confirm the current position with your vet and the ferry operator rather than trusting a forum post from years ago. Book pet-friendly cabins or kennels when you book the crossing, because they are limited and sell out first. Most ships restrict pets to designated areas, so decide in advance who walks the dog at the port.

6. Forgetting the first hour after you disembark

You have been sitting on a boat, you are tired, and suddenly you are on the right-hand side of the road. Set the satnav before leaving the ship — a job for the passenger — and be especially careful on the first roundabout outside the port, which is where most people briefly forget which lane they want. Carry a hi-vis vest for each person, keep them inside the cabin rather than the boot, and remember a warning triangle and headlamp beam deflectors. Some French cities require a Crit'Air emissions sticker, which must be ordered in advance, so check whether your route passes through a low-emission zone. France is also an hour ahead of the UK, which matters if you have booked a table for your first evening.

A five-minute check before you book

1. Route: compare the whole journey, including tolls and driving time, not just the fare.
2. Timing: put the check-in time in your calendar, with a buffer for traffic.
3. Documents: match names exactly, check passport validity and sort pet paperwork early.
4. Vehicle: declare roof boxes, bike racks and trailers when you book, not at the barrier.
5. Comfort: pack a crossing bag and keep valuables and medication with you.
6. Arrival: plan the first hour — satnav, deflectors, hi-vis, fuel and a sticker if you need one.

Get those right and the crossing becomes the easy part of the trip: the bit where you can sit down with a coffee, watch the wake, and remember that the holiday has already started.

Photo: Talha Resitoglu / Pexels