Optus has agreed to pay a $100 million fine after it was found to have unlawfully sold mobile phones and contracts to hundreds of vulnerable customers, many of them First Nations Australians.

The Australian Competition and Consumer Commission (ACCC) said more than 400 customers were affected between August 2019 and July 2023, with misconduct occurring at 16 stores across the country.

Customers included individuals with cognitive impairments, limited English skills, or low financial literacy, as well as people who were unemployed or financially dependent.

Optus staff were found to have pressured consumers into buying products they didn’t need or couldn’t afford, failed to explain key terms, and in some cases sold contracts without checking if network coverage was available in the customer’s area.

Some customers believed products were free or bundled at no extra cost.

“Many of these consumers who were vulnerable or experiencing disadvantage also experienced significant financial harm. They accrued thousands of dollars of unexpected debt, and some were pursued by debt collectors, in some instances for years,” said Catriona Lowe, ACCC Deputy Chair.

Optus said the misconduct primarily occurred at its Darwin store, with improper debt referrals traced to Mt Isa.

Optus CEO Stephen Rue apologised to affected customers and said the company had failed to act swiftly enough when issues were first reported.

“I am leading the implementation of extensive changes across the company,” Rue said.

In addition to the proposed $100 million penalty now considered by the Federal Court for approval, Optus will enter a court-enforceable undertaking to refund affected customers, guided by input from financial counsellors and community partners.

It will also contribute $1 million to digital literacy initiatives for First Nations Australians and introduce new training, credit checks, and a network coverage tool to prevent similar incidents.