Telstra has confirmed that more than 600 calls to triple-zero emergency services failed during Wednesday's nationwide network outage, caused by a software defect that crippled mobile services, disrupted train networks and knocked out card payment systems across Australia. The full scale of the crisis emerged at a press conference on Thursday, where Telstra's chief financial officer Michael Ackland described even a single missed emergency call as "unacceptable".
The outage began in the early hours of Wednesday morning, with users reporting loss of mobile signal and internet access from around 4.30am. Telstra declared the primary fault resolved by 4pm the same day, but a secondary issue affecting triple-zero calls only became apparent after engineers had addressed the original problem — leaving emergency lines compromised for longer than initially understood.
More than 600 emergency calls failed, hundreds of welfare checks completed
Ackland confirmed on Thursday that while roughly 33,000 triple-zero calls successfully connected to emergency services during the outage, more than 600 failed to connect. In total, Telstra carried out 639 welfare checks on customers whose emergency calls were unsuccessful or dropped out.
Of those checks, 230 callers responded to an SMS advising they did not need assistance. A further 402 cases required follow-up phone calls, while 170 were referred to police for further welfare checks. Seven callers indicated they did require help, and their details were passed to the relevant emergency services.
"One missed call is unacceptable," Ackland said. "Which is why we have the welfare check process in place, so that we are as rapidly as possible following up with people whenever there is a failed call."
The volume of welfare checks had come as a surprise. On Wednesday afternoon, Telstra had completed 333 checks — a figure Ackland acknowledged was already higher than anticipated. By Thursday, that number had nearly doubled to 639. "The volume of these welfare checks was higher than we expected and it has prompted us to investigate further," he said.
A software defect with a secondary fault at its core
Telstra traced the original outage to a timekeeping malfunction in network nodes located in data centres in Sydney and Melbourne. "Time synchronisation in those nodes wasn't working as it should. We don't know why," Ackland said.
The triple-zero failures, however, stemmed from a secondary fault that only surfaced once the primary issue was being resolved. "Last night, we identified a subsequent issue that was impacting some calls, including triple-0. And the nature of this only became apparent as we resolved the original issue," Ackland explained. "The issue is a consequence of the same software defect — while we addressed the original issue, that subsequent issue remained ongoing and needed to be addressed in a different way."
Engineers worked through Wednesday night to implement a fix, and Ackland said no further welfare checks have been required since the solution was deployed. "Customers can feel confident in calling triple-0," he said, while also acknowledging that the disruption to triple-zero calls extended beyond the initial outage window.
A full root-cause investigation is underway. "We will continue to investigate, continue to dig deeper, continue to go down all avenues to ensure that we're doing everything that we can to make sure that our system is as robust and reliable as possible," Ackland said.
Trains, payments and minister's reassurances
Beyond the emergency services impact, the outage had significant flow-on effects across the country. The entire regional Victorian train network ground to a halt, while regional and intercity services in New South Wales also experienced major delays. EFTPOS payment systems failed at small businesses nationwide, which Communications Minister Anika Wells described as "incredibly frustrating".
Wells was careful to distinguish the event from past incidents, assuring the public it was "not a triple-zero outage" but rather "a Telstra retail outage that has affected their customers right across the country." Emergency Management Minister Kristy McBain noted that Australian phones are required to fall back to other networks for triple-zero access.
Prime Minister Anthony Albanese moved to dampen speculation about a malicious attack, with Telstra itself making clear the fault was internal — a software defect, not sabotage.
Senator's test calls draw condemnation, CEO cuts holiday short
The outage also sparked a political controversy, after opposition communications spokesperson Senator Sarah Henderson admitted she had called triple-zero twice on Wednesday as a test to check whether the emergency line was functioning. Making improper calls to triple-zero is a Commonwealth offence carrying a penalty of up to three years in prison.
Industry and Innovation Minister Tim Ayres called the decision reckless. "I was absolutely shocked by that revelation. I just say to Australians, don't do what she did — it's utterly irresponsible," he said. Henderson defended herself, saying she was acting in her capacity as shadow minister to hold the government to account, but said she accepted the criticism.
Meanwhile, Telstra chief executive Vicki Brady cut short an overseas family holiday, with Ackland confirming she "got on the first plane that she could get on to" and would be back in Australia on Friday.
Telstra, which serves approximately 24.9 million retail customers according to its most recent annual report, said it was "so sorry" for the disruption. "We know how much our customers rely on our network and understand just how much of a disruption this is to your day," the company said in a statement.
