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It's been a feature of phone coverage for decades, but in the coming months, all of Australia's 3G networks will have been switched off, impacting millions of devices across the nation.
The shutdown began late last year when Vodafone became the first telco to switch off its 3G network, and the next stages are close to beginning with Telstra and Optus to shut off in late October.
This is what you need to know about it.
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When is the 3G network shutting down?
Australia's 3G networks are shutting down in stages.
Vodafone was the first company to switch off its network, shutting it down between December 2023 and January 2024.
Telstra and Optus will follow, with all its 3G services ending on October 28.
Telstra had been slated to flick the switch on August 31, but pushed back its shutdown date in order to give customers more time to update their devices.
Meanwhile Optus was due shut its 3G doors in September.
"We have to make sure everyone is ready to make this transition together – and we know some of our customers are still working through the steps they need to take to upgrade their devices," Telstra CEO and managing director Vicki Brady said.
"That's why we've decided to provide more time and further support."
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How many people will the shutdown affect?
While we don't know exactly how many people the shutdown will impact, an estimate in 2023 put the number of 3G-reliant devices in Australia at about 3 million – most of which are older ones that have been around for at least five or six years.
These include phones, eftpos machines, cars, tablets and security cameras.
All of them will stop working after the shutdown.
The Australian government also said about 740,000 4G phones will be unable to call triple zero emergency services after the shutdown, as they rely on the 3G network to make those calls.
That number has now dropped following proactive efforts from both Telstra and Optus to get people to upgrade their devices, but could still be as high as 150,000 on the Optus network alone by the time the shutdown begins.
"We're still reducing the number of customers (impacted), but it could be in the order of 100,000 to 150,000," Optus head of new products Harvey Wright told a Senate inquiry.
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Of the 3 million total 3G devices identified in 2023, it's estimated that 200,000 are medical alarms.
"An elder or someone else with a vulnerability who is relying on that alarm for an emergency response simply won't get one," David Waldie from medical alarm company Eevi said.
Speaking to 9news.com.au on December 12 – a few days before its shutdown began – a Vodafone spokesperson said the 3G network carried less than one per cent of its network's total mobile data traffic.
The bulk is carried by the 4G network, making up 85 per cent, while the 5G network is at slightly more than 13 per cent.
"We publicly announced the closure of our 3G network in September 2022 to provide 14 months' notice and plenty of support for our customers to prepare for the move to superior mobile technologies," the Vodafone spokesperson said.
"The 3G switch-off will impact a small number of our customers who have 3G-only devices or non-VoLTE devices. Our priority through this process is to ensure they have a 4G or 5G compatible device so they can continue using our network."
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There are some concerns that switching off the 3G network will reduce mobile coverage in regional areas that don't yet have access to 4G or 5G.
Telstra said it is committed to providing 4G coverage in all 3G areas before the shutdown. Optus has made no such commitment on its website, while Vodafone said its 4G coverage is "similar in size" to its 3G offering.
How do I find out if my device is affected?
The easiest way to find out whether a device you have is going to be affected by the shutdown is to contact the manufacturer.
"Don't put off checking that device, make sure you get to that as soon as possible to make sure you're not caught out," Stephen Fenech from Tech Guide said.
You can also get in touch with your phone provider.
Customers on any network can SMS "3" to 3498, and they'll be told by the telco whether their handset needs to be updated.
Optus has put out a list of its 20 most-used devices that will be impacted, which includes the iPhone 5, 5C and 5S, Google Pixel 2 XL, and Samsung Galaxy S5, and is also contacting customers it thinks will need to get a new device.
It and Telstra have been proactively reaching out to people on handsets that are about to lose functionality, and both of the major networks have provided phones to people experiencing hardship.
Vodafone reports it sent out over one million text messages and emails to its customers notifying them of the shutdown and providing information on how to upgrade their phone or device.
The telco recommends those with 3G-reliant or non-VoLTE devices visit their nearest Vodafone store or call 1555 to discuss upgrading their device.
Some companies, like Eevi, are reaching out to customers to make sure they stay connected.
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What can I do if my device will be impacted?
In short, you'll need to purchase a replacement that is compatible with the 4G or 5G networks if you want to keep accessing phone and internet services.
In some cases, this might be as simple a task as changing your SIM card from a mini or micro SIM to a nano one, while in other cases you may need to buy a whole new phone or other device.
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Why is the 3G network shutting down?
While 3G used to be the main pillar of mobile coverage around Australia, it's now used far less frequently, as modern devices instead rely more on the faster 4G and 5G networks.
That means phone providers have a huge amount of their network dedicated to a service that isn't used – and is only going to become less and less relevant in the future.
By shutting down 3G coverage, a provider like Telstra or Optus can take the radio frequency bands it used for that network and repurpose to improve and expand 4G or 5G coverage – a process known as "re-farming".
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"The demand and the consumption of data has been increasing exponentially," Chris Taylor from Telstra said.
"That's why we need to move our customers onto the 4G and 5G networks."
The process isn't unique to Australia – similar 3G shutdowns have happened or been announced in the UK, USA and New Zealand.
