Trafalgar, Insight Vacations, Contiki and Cosmos have suspended tours.
Trafalgar, Insight and Contiki have cancelled all tours in Europe, the UK, the Middle East and Asia from March 13 to April 30.
Cosmos is also suspending all global operations for travel until the end of April.
Trafalgar and Insight guests booked on a guided holiday during the suspension may change their travel dates or destination to any time in 2020 or 2021, with a full credit of all monies paid redeemable against tours with Trafalgar, Insight, Luxury Gold, Brendan Vacations, Costsaver, Uniworld, to any destination.
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For guests with existing bookings to Europe, UK, the Middle East and Asia departing from May 1 and more than 30 days from today for other destinations, or any new bookings being made, the operator is temporarily offering a waiver for the cancellation charges up to 30 days before departure.
Guests currently travelling in Europe, UK, the Middle East and Asia have the option to continue their travels or return home early and receive a pro-rata travel credit for the unused land portion of their trip.
Trafalgar trips operating in North and South America, South and East Africa, Australia and New Zealand are operating as planned.
Insight trips operating in North America are operating as planned.
Contiki said it would be contacting customers to help them rebook free of charge on to a new trip in any destination for travel any time during 2020 or 2021.
Travellers currently travelling in Europe, the Middle East and Asia with Contiki can continue their travels or return home early and receive a pro-rata travel credit for the unused land portion of their trip.
Due to new quarantine requirements in Argentina, Contiki has also suspended the March 21 departure of its Patagonia Trail.
Cosmos is offering customers the option to move travel dates or cancel bookings for travel on holidays before April 30.
For travellers with existing bookings and for new bookings after April 30, deposits on future Cosmos holidays can be moved to any other brand (Globus, Cosmos or Avalon Waterways), destination or itinerary in 2020 or 2021 without penalty.
Cosmos is temporarily waiving cancellation penalties until three days before Europe departures.
Chief executive of Cosmos and Avalon Waterways UK Giles Hawke said: “We recognise that agents and their clients are faced with a great deal of uncertainty right now, and we are committed to helping them through this situation with the right options, adequate time and high levels of attention and consideration.
“We are doing our best to cater to each and every traveller and help them feel confident in their decision to explore the world with us.”