About 2,500 jobs have been lost and 64,000 bookings cancelled with the collapse into administration of Specialist Leisure Group.
The hotel and travel company included well-known coach holiday brands Shearings and National Holidays.
Trade organisation Abta said the company, which specialised in products for the over-50s, was “significantly impacted” by the coronavirus pandemic.
It struggled to provide thousands of refunds for cancelled trips, Abta said.
It added that the vast majority of cancelled bookings were coach package holidays, which are financially protected. Customers with these bookings will receive a full refund, Abta said.
The Specialist Leisure Group, based in Wigan, also operated Caledonian Travel and hotel businesses such as Bay Hotels, Coast and Country Hotels and Country Living Hotels.
The firm said on its website that all tours, cruises, holidays and hotel breaks had been cancelled and would not be rescheduled, blaming the impact of the coronavirus pandemic.
Employee Matthew Herbert said he was “gutted” upon hearing the news.
“It’ll take a while for this wound to heal. To my colleagues, good luck, stay safe, stay strong,” he wrote on Twitter.
John de Vial, Abta’s director of membership and financial services, said: “Today is a very sad day for these customers and the thousands of staff who will have lost their jobs.
“The fact that two such well-known brands with a loyal customer base have had to call in administrators is a stark indication of the pressure that the holiday industry is under as a result of the coronavirus pandemic.
“Abta has repeatedly highlighted to the government the urgency of the situation and the need to set out a co-ordinated strategy with clearer communication if it wants to help avoid significant job losses and support companies to weather the storm.”
Other coach companies sent messages of support.
Runcorn-based Anthony’s Travel mourned the loss of a firm said in a tweet Shearings was “long-associated with the golden age of coach travel and UK tourism”.
Teesside-based Skelton Coaches urged the government to “help the coach and tour industry before it’s all gone”.
Atol, the government-run financial protection scheme, said it would be contacting the small number of customers with flight-inclusive packages, which would be protected.
Atol spokesman Andrew McConnell said: “This is a particularly sad day for customers and employees of Shearings Holidays Ltd, a long-standing business and well-known UK travel company.”
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