Telstra chief executive Vicki Brady has publicly apologised for this week’s nationwide network meltdown, admitting Australia’s biggest telecommunications company “let our customers and Australians down” as pressure mounts over compensation, customer trust and the reliability of the nation’s largest mobile network.

Facing a barrage of questions following one of the worst outages in Telstra’s recent history, Brady conceded the company had failed customers after the outage crippled mobile and data services, disrupted retailers, halted freight rail operations and left more than 600 failed Triple Zero calls requiring emergency welfare checks.

“We have let our customers and Australians down, and for that I am deeply sorry,” said Brady, who returned from a family vacation to front the media.

“It’s extremely disappointing and disruptive when services aren’t available. We understand what caused the issue and will complete our investigation into the actions needed to prevent it from happening again.”

The outage began at 4.20am on Wednesday when a software defect triggered a failure in a critical network time synchronisation system after equipment restarted, causing faults to progressively spread across Telstra’s national mobile network.

“Networks are large and complex,” Brady said. “When something goes wrong, we’re committed to taking accountability, giving people clear information and fixing issues as quickly as possible.”

Chief financial officer Michael Ackland (pictured below) said Telstra now believed all customer services had returned to normal.

“We believe everything is back to normal,” he said. “Australians can feel confident in calling Triple Zero.”

Ackland revealed the outage “started with a software defect that was unexpected”, adding that “time synchronisation is critical to the way all networks run, and clearly it has been a vulnerability.”

The company confirmed it has launched a detailed investigation into the software failure and will determine what engineering changes are required to prevent a repeat.

Questions also centred on reports that a South Australian woman died after her husband allegedly experienced difficulty contacting Triple Zero during the outage.

Ackland said Telstra had conducted a detailed review of network records and was continuing to assist South Australian Police.

“Our thoughts are with the person’s family and loved ones,” he said. “To date, we can see no record of calls from those numbers accessing Telstra’s mobile network to call Triple Zero.”

The company stressed the police investigation remains ongoing.

Brady also rejected suggestions that Telstra’s recent job cuts or organisational restructuring contributed to the incident.

“Our people and our processes worked as they should have,” she said. “There is no indication that any restructuring of jobs has impacted this particular issue.”

Compensation was another flashpoint.

Ackland confirmed affected customers would only be compensated through Telstra’s existing complaints process.

“We will compensate customers under our normal BAU processes,” he said, without explaining that BAU refers to “business as usual” procedures, meaning customers will need to contact Telstra and have claims assessed individually rather than receive automatic compensation.

Asked why Australians should continue paying premium prices for Telstra following the outage, Brady admitted the company now faced the challenge of rebuilding customer confidence.

“We’ve got a job to do to rebuild that trust with our customers,” she said.

The outage has already triggered scrutiny from Communications Minister Anika Wells, renewed calls for tougher reliability standards across Australia’s telecommunications sector, and questions over whether carriers providing critical national infrastructure should face mandatory uptime requirements and automatic customer compensation when major failures occur.