STA Travel UK has gone out of business, the Civil Aviation Authority (CAA) has said, in news that will leave thousands of customers chasing refunds.

The company employed around 500 staff in 50 high street branches and its central London headquarters. It is the latest travel business to shut down after global tourism ground to a halt as a result of coronavirus.

The long-established agency – whose initials are derived from its original parent company, Student Travel Australia – specialised in cheap air fares and adventure tours for young people

When restrictions started coming into effect in March, many trips were cut short, or did not begin. Long-stay trips to distant destinations, which was the mainstay of STA Travel, have since been near-impossible to undertake.

On Thursday, Qantas said that it would not operate intercontinental flights to and from Australia before the second half of 2021.

Australia and New Zealand were key markets for STA Travel UK.

Thousands of customers whose trips were cancelled have been trying to claim money back for months, with the company offering only partial refunds or vouchers.

The CAA told customers: “We are aware of a number of consumers whose bookings have been cancelled by STA Travel Ltd as a result of government advice or flight cancellations.

“Consumers that have accepted valid refund credit notes or are due refunds for the cancellation of their Atol protected booking will be able to submit a claim to Atol through our online portal.”

“If consumers have a flight-only booking that was Atol protected, they will only be able to make a claim if they are still due to travel and have not received a valid ticket.

“Otherwise, consumers should speak to their airline, including if the flight has been cancelled or they have received a voucher for a cancelled flight.”

A spokesperson for Abta, the travel association, said: ”People will have used STA Travel to book package holidays as well as individual air tickets.

“The majority of holidays sold were flight-inclusive packages, which are protected by Atol, and scheduled airline tickets only which should proceed as normal.

“Non-flight based packages will be protected by Abta.

“If customers booked a package holiday through STA Travel, and the holiday is provided by another tour operator, they will need to contact the tour operator who should be able to confirm that their booking will go ahead as normal.

“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.”

The company was licensed to carry around 30,000 package holidaymakers a year under its Atol bond. Many more customers bought flight-only tickets or land arrangements which do not have the same protection.

The agency’s Swiss parent, Diethelm Keller Group, filed for insolvency on Thursday but said that it hoped individual businesses could continue trading.

“Sales have not picked up as anticipated, due to consumer uncertainties, further restrictions and renewed lock-down measures, which are expected to largely continue into 2021,” it said in a statement. “As a consequence, STA Travel Holding AG, is filing for insolvency.”

Online visitors to STA Travel UK are told: “The website is currently down for maintenance, but will be back shortly. “If you wish to make a new booking, please give us a call.”