So planning way in advance for next summers holiday when should the ferry for summer school holidays be booked? Is there a window that all the cheap crossings come out? Is it to early to be thinking about ferries? I got a price for one and it was over £500 from portsmouth to le Havre. Not sure what route to take. What is the cheapest crossing? Don't fancy going to Dover as it is 4-5 hour journey for us.