Booking.com's chief executive Glenn Fogel told the BBC that holiday "prices are already going up".
Many airlines have significantly reduced the number of flights they operate due to travel restrictions.
Despite huge demand, uncertainty makes it hard for airlines to plan bringing more planes back into service, he said.
"There's so much pent-up demand," said Mr Fogel. "Everybody wants to go travelling, but we all want to do it safely."
John Grant, an aviation analyst with global travel data provider OAG agrees that this will have a knock-on impact on airfares as travel restrictions are eased.
"That will, in the short term, create a rush of pent-up demand and revenge spending," he said.
"In turn, the airline algorithms will detect an uptick in demand and move prices up accordingly".
A lack of clarity about how governments will go about recognising vaccine and testing statuses from other countries is troubling the travel industry, which has been hit hard by the coronavirus pandemic.