Inghams has suspended all its departures to Switzerland for this December following new quarantine rules on arrival.
The ski operator said customers were now being offered the option to move their booking free of charge or cancel their booking and receive a full refund.
Currently only holidaymakers whose final destination is Switzerland are affected, not those transiting to ski resorts in other destinations such as France, the operator said.
In a clarification to earlier Foreign Office travel advice for Switzerland, customers in transit and travelling on to another country do not need to quarantine provided travel through Switzerland is for less than 24 hours and does not involve a stopover.
Ski holidays in Switzerland account for around 6% of Ingham’s winter programme and the operator said bookings had to-date been strong for the winter 2021-2022 ski season.
In a statement, the operator said: “We are extremely disappointed for all our customers who were looking forward to a ski holiday in Switzerland in the coming month.”
In addition, the operator is allowing all ski holidaymakers the opportunity to alter their ski break to a later date or different destination.
It said: “While many of our customers remain eager to return to the slopes, we understand that some customers with later departure dates may be feeling apprehensive about their holiday following this latest update.
“With this in mind, we continue to offer flexibility via our ‘No Fee to change up to 28 days before departure’ policy.”