Optus customers in Victoria, South Australia, Tasmania and the Northern Territory experienced a technical fault last week that disrupted voice calls for around 76 minutes, prompting the federal government to commit to strengthening telco network resilience.

• What it is: A technical glitch affected Optus voice calling in four states, with some customers experiencing intermittent call dropouts, including impacts to emergency call access in some cases
• Who is affected: Optus mobile customers in the affected states during the outage window, plus any business relying on Optus voice services for time-critical communication
• What the risk is: The outage adds to a pattern of recent Australian telco reliability incidents, and highlights that a single carrier outage can affect emergency call access
• What to do: Businesses that depend on a single telco for voice services should consider a backup option, such as a second SIM on a different network or a VoIP failover

We recommend reviewing your business continuity plan for phone outages, particularly if you rely on mobile voice for customer-facing calls.