Student travel firm STA Travel UK has ceased trading, according to the Civil Aviation Authority (CAA).
The travel agency, which specialises in package tours for backpackers and young people, has more than 50 stores across the UK.
Abta, which represents tour operators and travel agents, said the news would send a “shockwave” through the tourism industry, which has taken a hit during the coronavirus crisis.
A statement posted on the STA Travel website on Friday said the company had collapsed, while reassuring customers that those with bookings would receive information in the coming days.
“Due to the recent announcement that STA Travel UK has ceased trading, unfortunately our travel experts are unable to assist you at this time,” it said.
“Please be assured that if you had a previous booking with us, or hold a live booking, you will receive further communication in the coming days.
“We are sorry for the inconvenience and the limited information available to you at this time.”
Andrew McConnell, spokesman for Atol, acknowledged it would be a cause for concern for anyone who had booked through the company or had their plans cancelled.
“It is a sad day for the industry when a long established business like STA Travel Ltd ceases trading, especially one that many may be used to seeing in their towns and on their high streets,” he said.
Arrangements are being made for Atol protected customers to continue their holiday and return home as normal, or make a claim if they were due to travel, he added.
An Abta spokeswoman said: “The news that STA Travel Limited, which was a long-standing Abta member, has ceased trading will send a shockwave through the industry, bringing to life the very real pressures that travel is under at the moment.
“STA Travel will be a name that is familiar to most people who will have used them to travel or been aware of their name on the high street, and this distressing news will sadly affect the livelihoods of hundreds of employees.”