It comes as the airline prepares to fight ACCC allegations in court that it sold tickets to flights it had already cancelled and months after the early exit of former CEO Alan Joyce.

Brand Finance’s study measures both a brand’s value, which takes into account earnings, and its strength, which focuses more on its reputation with the public.

Qantas scored a strength rating of 71.35, putting it behind Myer, Tip Top and Origin Energy.

The consultancy’s managing director, Mark Crowe, said its 10-point drop was a “red flag” and reflected that something “very significant” had affected its reputation.

“Last year, when Qantas declined by four points, they saw decreases across value for money, recommendation, reputation and loyalty,” Crowe told the AFR.

“But this year, these decreases have become more profound. And they come at a time when, if you looked at our global 500, many airlines are increasing in brand strength and brand value.”

The top five ranked for brand strength were Bunnings, in first place, followed by NRMA, Woolworths, Telstra and JB-Hi-Fi.

The bad result for Qantas comes months after the ACCC revealed it would take the airline to court over allegations it sold more than 8,000 tickets to flights it had already cancelled, and calling for a $250 million fine.

The decision to go ahead with legal action came from an analysis of data showing Qantas cancelled almost a quarter of flights between May and July 2022, or 15,000 of 66,000 scheduled domestic flights departing from all states and mainland territories.

The watchdog said that for 70 per cent of these cancelled flights, Qantas “continued to sell tickets for the flight on its website for two days or more, or delayed informing existing ticketholders that their flight was cancelled for two days or more, or both”.

In its response to the ACCC’s case, Qantas said it sold passengers “bundles of contractual rights” rather than tickets to any particular flight and blamed “human error and process failures” for the delay in informing customers.

“In purely legal terms, the ACCC’s case ignores a fundamental reality and a key condition that applies when airlines sell a ticket,” Qantas argued.

“While all airlines work hard to operate flights at their scheduled times, no airline can guarantee that. That’s because the nature of travel – when weather and operational issues mean delays and cancellations are inevitable and unavoidable – makes such a guarantee impossible.

“For this reason, our promise is to get customers on their way to their destination as close as possible to the flight time they book, either on their original or an alternative service at no additional cost. If not, we offer a full refund. This is consistent with our obligations under consumer law and is what we did during the period the ACCC examined.”