Optus has introduced 24-month express repair warranties for all brands of mobile phones on 24-month contracts following an investigation by the Australian Competition and Consumer Commission (ACCC).
The ACCC had been concerned that consumers who complained of faulty handsets were only covered by the handset manufacturer's express warranty policy.
Optus has undertaken to provide the warranties for all phones it provides under 24-month contracts for the next three years.
ACCC chairman Graeme Samuel said the undertaking was a win for consumers.
"Optus has joined the other major telcos in providing 24-month warranties, and we now have a situation where consumers who purchase a mobile phone on a fixed contract have a warranty for the life of the contract," he said.
Vodafone Hutchison Australia and Telstra have also provided undertakings to the ACCC for the provision of 24-month warranties for phones provided under 24-month contracts.
"Retailers take note — you cannot wipe your hands clean of a faulty product just because the manufacturer's warranty period has ended, particularly when your product is supplied in conjunction with a lock-in contract that is longer than the manufacturer's warranty period," Samuel said.
"The law gives consumers a basic, guaranteed level of protection for goods and services they acquire and such rights and guarantees cannot be excluded or limited by suppliers. In fact, any representation by a supplier that seeks to exclude or limit these rights and guarantees available to consumers is illegal."
The new consumer guarantees arrived 1 January as part of Australian Consumer Law.