Channel Tunnel high-speed rail company Eurostar said it will be carrying more than 420,000 people from December 20 to January 3 - an 11 per cent rise on the same period 12 months ago.
In the UK, an estimated £2 billion is being spent on travel to friends and families this Christmas, and the RAC is predicting that 13 million people will take to the roads from December 24 to 26.
Traffic information company Inrix warned that journey times could triple at the busiest festive time, with shopping areas being particularly busy this weekend and again on Friday 27.
VisitEngland said around 20 per cent of the adult population planned to spend at least one night away from home over the festive period, with these trips boosting the UK economy by around £1.9 billion.
A spokesman for rail industry organisation the Rail Delivery Group said: "As fewer passengers travel over the festive period, we can continue one of the biggest programme of improvements in the railway's history while ensuring the vast majority experience no disruption whatsoever."
A series of accidents on major road routes hampered the getaway this morning. One of the worst-hit areas was the M5 at Bristol, where an overturned van led to long tailbacks.
Air traffic control company Nats said that air traffic was likely to be reduced between Christmas Eve and New Year's Day, with around 1,400 flights on Christmas Day and around 3,900 on both Christmas Eve and Boxing Day.