Christmas train passengers are set to travel outside the five-day "bubble" window amid fears of overcrowding, an analysis for The Telegraph reveals.

Rail travel over the festive period will peak at 11am on December 23 – the day coronavirus rules are relaxed for five days, meaning up to three households can mix – but thousands plan to travel before the change.

Some of the UK’s biggest stations will see an increase in demand of up to four times in the week before the change and will be three times busier in the days after the tier system returns, according to data from Zipabout, a technology company that advises the Government on overcrowding.

The analysis – which uses forecast data as opposed to historic journeys – shows that London Euston will be the busiest station over the festive period, with demand increasing by nine times on December 23.

Change in demand

The most popular time to travel that day is between 11am and 1pm, with routes to and from the North-East the busiest.

The findings come amid warnings from train operators and Grant Shapps, the Transport Secretary, that passengers should plan ahead because social distancing measures will mean reduced capacity.

Crispin Humm MBE, the chief business development officer at Zipabout and a former head of customer strategy at the Rail Delivery Group, said knowing which trains are most popular would allow passengers "to follow Government advice and plan ahead and avoid busy services".

Six of the 10 busiest stations will be in London, while Edinburgh, Manchester, Leeds and Brighton will also see high volumes of passenger traffic, the analysis shows. At Euston – as all over the UK – the peak day is set to be December 23, when demand increases by nine times.

London Euston rail station

Leeds rail station

However, the data also shows that people are planning to travel outside the five-day window, with the four days leading up to Christmas being, on average, five times busier than usual. Demand will increase by 3.6 times on Friday December 18. On Monday 21 it is set to go up by four times busier, and it will be 3.8 times times busier the following day.

Similarly, data shows that most people are not intending to travel home on Sunday 27, when the easing of restrictions comes to an end. While demand that day is 1.4 times higher, the following day sees a three times increase and December 29 and 30 a rise of just above two times.

The pattern, which will also see the weekend before Christmas quieter than weekdays, is echoed at Leeds, where the station is set to experience four times its usual footfall on December 23.

The 10 stations set to be busiest over Christmas

The Government guidance says: "You should not travel to see your bubble before December 23, or travel back after December 27, except in exceptional circumstances."

People in Tier 2 areas are allowed to travel to hotels or guest houses outside their local area with their households or support bubble, but those in Tier 3 should avoid travelling "wherever possible".

Rather than relying on historical data, Zipabout is the first company to forecast demand by analysing passengers’ interactions with online journey planners and departure boards. Its technology powers the Alert Me service, which provides real time updates and is available through the National Rail Enquiries website and Messenger.

Mr Humm said: "The UK railway is the only one in the world which has access to Zipabout’s unique forecast demand data. We are using it to power personalised messaging and help passengers travel easily and safely.

"Passengers will be able to follow Government advice and plan ahead and avoid busy services over Christmas by using the Alert Me by Messenger service on National Rail Enquiries. A service which can be extended across the entire transport network and will be made available to all UK rail operators shortly thanks to the support of the Government and Rail Delivery Group."

Rail minister Chris Heaton-Harris confirmed last month that "the Rail Delivery Group is currently preparing for a wider roll out of Alert Me to include the train operators’ own digital platforms".

Demand may change as people alter their plans as Christmas draws closer and the Government is due to announce proposals to ease overcrowding, which The Telegraph understands will include an increasing services and carriages on busy routes.

Labour has called for peak fares to be scrapped as part of the plan, but the analysis shows that people are not currently planning to travel in the traditional rush hour, with lunchtime the most popular time between December 23 and 29.