Posted Thu 30 Jul 2026 at 10:40amThu 30 Jul 2026 at 10:40am, updated Thu 30 Jul 2026 at 10:57amThu 30 Jul 2026 at 10:57amAn Optus outage in September 2025 affected some people's ability to connect to the emergency call service. (AAP: Bianca De Marchi)The nation's second largest telco, Optus, is being sued in the Federal Court over last year's major network outage in which hundreds of calls failed to reach Triple Zero.The Australian Communications and Media Authority (ACMA) alleges Optus breached two legal obligations more than 1,000 times.These included making sure customers who made emergency calls had access to the emergency call service and to ensure those calls were carried appropriately.The maximum penalty available to the court is $250,000 per contravention.The massive outage, which occurred last September, went for almost 14 hours and was linked to two deaths. During the 14-hour outage 75 per cent of Triple Zero calls failed from a total of 605 attempts.In December, Optus released a review it commissioned by experienced business and public service executive Kerry Schott, which found widespread failures contributed to the outage and prevented a faster resolution.The report found a routine network upgrade was plagued by multiple failures by Optus and its contractor Nokia — with as many as 10 crucial mistakes being made.It found the Optus call centre did not escalate warnings from five callers who said Triple Zero calls were failing.The report said Optus needed to overhaul its network operations which "clearly failed" and improve risk management and internal audit functions.ACMA Chair Nerida O'Loughlin said the public must be able to access Triple Zero in an emergency."Australians rightly expect that when they call Triple Zero, their call will connect. The circumstances of this outage meant that did not reliably occur, leaving people unable to connect to potentially life-saving services," Ms O'Loughlin said."Giving access to the emergency call service is not optional, it is a fundamental legal obligation and the most important public safety responsibility telecommunications providers have."Optus has been contacted for comment.