Telstra's mobile network suffered a widespread outage in the early hours of Wednesday morning, cutting off thousands of customers from mobile calls and data services across every mainland capital city and several regional areas. Reports began flooding in from around 4:15am AEST, with the disruption leaving some users' phones displaying SOS-only mode and prompting an urgent investigation by the country's largest telco.

Telstra confirmed it was aware of the problem, stating it was "looking into an issue affecting some mobile calls and data connections," but the company had not provided a cause, an estimated restoration time, or a figure for how many customers were caught up in the disruption as of early Wednesday morning.

Scale of the Telstra outage

While Telstra's initial statement characterised the problem as affecting "some" services, the volume of complaints suggested a far more significant event. Outage-tracking platform Downdetector recorded a sharp spike in reports beginning around 5am AEST, with more than 7,000 complaints lodged by early morning. Those reports came from customers in Sydney, Melbourne, Brisbane, Perth, Canberra and Adelaide, as well as regional centres across Victoria, Queensland and Tasmania.

Frustrated customers vented on social media, with many noting that some of their devices were connecting normally while others showed no service at all. Several users reported their businesses had been disrupted, and others expressed concern that they were unable to reach emergency services. A number of customers demanded more detailed updates from the company well over two hours after the outage first emerged.

"If you're having trouble connecting, try again as it may work on a retry," a Telstra spokesperson said. "We're on it and will share an update as soon as it's fixed. Thanks for sticking with us."

The telco also advised affected customers to try restarting their devices or switching to Wi-Fi where possible while the issue was being investigated.

Flow-on effects: virtual networks and EFTPOS payments

The disruption extended well beyond Telstra's own customer base. Because a number of smaller carriers operate as mobile virtual network operators running on Telstra's wholesale infrastructure, those providers were also caught up in the outage. Services affected included Boost Mobile, Belong, Aldi Mobile and Tangerine Telecom, meaning the total number of impacted users was likely considerably higher than Telstra's own subscriber base alone would suggest.

The outage also had commercial consequences beyond telecommunications. EFTPOS payment processor Tyro said it was investigating "possible system issues" linked to the network disruption, warning that some of its customers may be unable to process card transactions over the 4G network.

"We're aware of an issue with a national telephone network provider and that some customers may not be able to connect to the 4G network right now to process eftpos transactions," Tyro said in a statement.

The payments company recommended affected businesses switch to an ethernet or Wi-Fi connection as a workaround until mobile connectivity was restored. Tyro stressed the problem was outside its control but said it was actively monitoring the situation.

A troubled recent history for Australia's biggest telco

Wednesday's outage arrives at a sensitive time for Telstra, which has faced growing scrutiny over network reliability and its obligations to customers. The company was fined more than $3 million in 2024 following a major system failure in March of that year, which disrupted Triple Zero emergency service lines — a lapse that drew significant public and regulatory concern.

Some users caught up in Wednesday's outage again reported difficulty connecting to emergency services, raising fresh questions about the resilience of critical infrastructure during network failures. In the 2024 incident, a technical fault had caused a failure to pass caller information through to emergency services, compounding the severity of the disruption.

Separately, Telstra made headlines at the end of June when it slashed its claimed mobile network coverage by almost a third after new regulatory rules came into force. The changes require telcos to measure and report signal strength using a standardised methodology, making it easier for consumers to compare coverage across different networks. The revision was a significant restatement of the reach Telstra had previously promoted to the public.

According to the company's most recently available figures, Telstra provides approximately 24.9 million retail mobile services across Australia — a scale that underlines why any disruption to its network has such broad national consequences. For context, Australia's telecommunications sector has seen several high-profile outages in recent years, with the sector's reliability a persistent topic of debate among consumers and regulators alike.

What happens next

As of the time of publication, Telstra had not confirmed what caused Wednesday's outage, had not indicated when full service would be restored, and had not released a figure for the number of affected customers. The company said it would share an update once the issue was resolved.

Customers experiencing difficulties were advised to retry connections, restart devices, and use Wi-Fi calling where available. This story will be updated as further information comes to hand.