More and more business travellers are switching to rail where it is a viable alternative to air, new research by Carlson Wagonlit Travel (CWT) shows.
The TMC also said that corporates could make significant savings on train tickets by booking ahead.
Rail bookings led those for air on trips from London to Paris, Brussels, Newcastle and Leeds.
Only on journeys from London to Manchester was air ahead, with 51% of travellers choosing to fly.
On trips to the other cities rail was substantially ahead. 66% went to Brussels by rail, 65% to Paris, 97% to Leeds and 61% to Newcastle.
Nigel Turner, CWT's director of public sector UK, said the full opening of the Eurostar high speed service from its new station at St. Pancras, London last November, had had an obvious impact.
But he added: "It appears that there is a growing preference for domestic rail travel - driving this trend are issues of emissions, security and baggage versus airlines, improved rail services and reliability, and even price where business travellers have wised up to the savings that can be made with a bit of advance planning."
Mr Turner said CWT research on prices showed that substantial savings could be made when booking ahead.
He cited the cost of a first class ticket return from London to Manchester. If booked on the day, it cost up to £360 but if booked just a day ahead, it cost £175.50, a saving of £184.50.
He said it was a misconception that in order to get savings, bookings had to be made two weeks ahead.
"Although availability of low fares will be better the sooner you book, many advance purchase fares are available up until 18.00 the day before travel," he said.