Eurostar is launching £25 one-way tickets to Paris and Brussels but only to travellers who hand over their Facebook details.
The cross-channel operator has unveiled website Snap which lets users buy the cheapest fares but only if they log in via the social network site and they don’t mind what time they travel.
A spokesperson told BBT the fares will not be available on the GDS and only available through the dedicated site.
Passengers choose whether to travel in the morning or afternoon and only find out the time of travel 48 hours before departure.
This means anyone who chooses a weekday morning could end up travelling at 05:40am or if they opt for the afternoon journey they could be arriving into Paris at 11:32pm.
The company's commercial director, Nick Mercer, said: "Our research has shown that there is a strong appetite for spontaneous travel at great prices.
"With state-of-the-art trains boasting 20 per cent more capacity, travellers with a flexible schedule can look forward to a spur-of-the-moment trip at the lowest fare."
The promotional scheme is designed to increase occupancy on its new trains and also attract passengers who are more flexible about times they travel.
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