Optus will shut down its 2G network on 1 April 2017, indicating that only a fraction of its total mobile network traffic is delivered over the infrastructure.
The telco introduced the 2G GSM service in 1993, providing basic voice and text messaging services. The service introduced basic data services such as text-based sports results and stock prices, which have evolved into news and faster 3G and 4G networks to include live streaming video and mobile web browsing.
Telstra announced last month that it would also close its 2G network by the end of 2016.
Dennis Wong, acting managing director at Optus Networks, said greater smartphone usage and advances in 4G technology are driving customer preferences for more mobile data and faster speeds.
"There has been a steady decline in 2G traffic and customers in the last few years," Wong said.
"2G now constitutes a fraction of our total mobile network traffic and is declining significantly year on year. Mobile service providers globally, including in Australia, and our parent company, Singtel in Singapore, are closing down 2G networks to support new technologies."
2G customers are being asked to upgrade to newer 3G or 4G devices and plans.
Virgin Mobile and Optus Wholesale service providers using the 2G GSM network, including amaysim, will also be affected.
"Our priority is to prepare our customers for this change and ensure they have sufficient time to upgrade to newer devices. Optus will provide affected customers with more details about options available to them closer to the closure of our 2G network in April 2017. For some customers, this might be a simple SIM upgrade," Wong said.
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