Some Singapore Airlines (SIA) customers are upset with a new online booking feature that automatically includes travel insurance unless travellers opt out.

Once payment is made, asking for a refund is tedious, said those who realised they were charged for insurance only after their flight bookings were confirmed.

The feature was introduced last year in Singapore, Thailand and Hong Kong.

Mr George Lim, who wrote to The Sunday Times, said that when he asked for a refund, he was told to contact the insurance company.

"I protested as the payment was made to them (SIA)," said Mr Lim, who flies SIA twice a month. "I told them that if they didn't get the refund for me, I would cancel all five tickets I purchased."

Mr Allen Tan, who was also caught off guard, said in a letter to the Forum page: "While I understand that SIA needs to grow revenue, its senior management should work out proper ways of doing this, rather than slipping in surreptitious add-on charges such as this."

In its reply to Mr Tan, SIA said that it encourages customers to buy insurance to safeguard their travel plans. "The inclusion of insurance is clearly displayed, the cost is reflected in the booking summary panel at the payment page, and customers can opt out if they do not wish to add the insurance to their booking," said a spokesman.

Those who wish to cancel the insurance can do so even after payment is made. In such cases, refunds will be credited to the customer's credit card within 10 working days, said the spokesman.

SIA said it will continue to review and refine its policies and practices to better serve its customers.

The Consumers Association of Singapore (Case) frowns upon such practices, its executive director Loy York Jiun said. "It is common for consumers to overlook that such options have been ticked for them as they complete the transaction... This can lead to additional charges for extra services or items that the consumers may not be aware that they are purchasing."

Such options should be left unticked so that consumers have to consciously tick them if they wish to include them, said Mr Loy.

Those who have issues obtaining their refunds should approach Case for assistance, he added.

In Australia, the United States and Europe, consumer watchdogs have in the past warned airlines and other merchants against engaging in such practices. In 2016, Virgin Australia stopped the pre-selection of travel insurance on its online booking platform after discussions with the Australian Competition and Consumer Commission.

In Asia, it is also rare for full-service carriers to include such features, observers said.

This is not the first time SIA has upset some of its passengers.

Just two weeks ago, the airline said it would impose a credit card fee on bookings made by some travellers departing Singapore. The charge - 1.3 per cent of the total fare amount, capped at $50 - was to apply to those who bought its cheapest Economy Lite tickets, the airline said.

A day later, SIA, without giving any reasons, said it had decided not to go ahead with the credit card fee.

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