Australian consumers using 4G- or 5G-compatible phones say telecommunication companies and retailers are not doing enough to protect them from being left without critical access to mobile networks or needing to buy new handsets after the recent shutdown of the national 3G network.

Telcos are blocking mobiles from call and text networks to free up space for next-generation 5G handsets.

However, when 3G was switched off on October 28 some phones bought in recent years were impacted — even if they were advertised and sold as being able to use 4G and 5G frequencies.

The telco companies are legally required by a direction enforced by the national Australian Communications and Media Authority (ACMA) regulator to refuse service to all phones that relied on 3G to make emergency calls.

For some customers with 4G and 5G mobile phones, the shutdown caught them off guard, with their modern handsets suddenly disconnected from their networks despite those models still being available to buy from Australian retailers.

'They were quite rude about it'

Sujay Jain, an auditor from Melbourne, had been using a 5G-compatible Xiaomi Mi 10 mobile he bought in Australia on a plan he shared with his father and was told his connection was to be cut, but he was unaware why.

He said when he visited an Optus store, staff members were not helpful in advising what he should do next to access essential phone services.

"My experience wasn't the best. They were quite rude about it," he said.

"They kind of forced us into buying a phone.

They said, 'You can buy a phone, or there's the door — you can go out.'

"I am a fair bit out of pocket because initially I did buy the phone for $1,000, which isn't cheap and if I'm buying an phone for that much I would expect to use it at least four or five years.

The 24-year-old has reverted to using an older phone he had access to. But he said he would be forced to buy a new mobile if his current 5G handset was not reconnected.

"I would like to see some sort of explanation and reimbursement from these telco providers like Optus and Telstra," Mr Jain said.

"I'm guessing there are a lot of other people who are in the same situation as me."

'A complete lack of understanding and competence'

Retiree Bridget Clinch has been a Telstra mobile phone service customer for more than a decade and had been using a 5G-compatible ROG Phone 5 Android mobile before the 3G network was shut down.

Ms Clinch said she was unaware her connection would end after the October 28 shutdown until she called Telstra and was told her mobile had been relying on the 3G network.

"This is a 5G phone that cost me $2,000 and it's been working fine on Telstra since I got it," she said.

"[Telstra] confirmed that, no, it had only been using the 3G network even though it had all of the latest updates from Google, it had VOLTE (voice over LTE call and text) settings. It had a setting that would enable it to be 4G or 5G only.

The 45-year-old initially bought her ROG Phone from JB Hi-Fi, which still stocks the model. However, she has now reverted to using a six-year-old 4G Razer Phone 2.

Ms Clinch has also issued a complaint with Australia's Telecommunications Industry Ombudsman.

"They said, 'We can't make Telstra do anything,' and so that was where I was left," she said.

"That $2,000 phone that works fine is now e-waste and I've got to either downgrade to something that Telstra sells or try my luck … buying a phone that says it's 5G that might not work."

Ms Clinch said she wanted telcos like Telstra to test more handsets and be transparent about which phones no longer connected to mobile networks.

"Telstra should be going through and seeing what phones can work and enabling all the ones that can, rather than just blanket banning all the ones they don't want to sell."

'They've handled that absolutely terribly'

Jessica, who asked not to be identified by her full name, is a 43-year-old nurse who travels into regional and rural areas for work and bought a new, 4G- and 5G-compatible iPhone 11 from the online Apple store in 2021.

Her connection was with Boost Mobile, which operates using the Telstra network, but she said she was only notified after October 28 that her service was to be disrupted.

"The messaging that I was getting from them initially sort of hinted at that, but no-one ever said it explicitly," she said.

"All the pre-recorded messages that I get when I try and use it now say that your phone may not be able to call triple-0, and that's just insane.

"Accidents happen. I'm a nurse. I travel for work. I have to be able to call triple-o, and of course there's no way to test that … I'm worried that if I'm not in a metropolitan area it could be even more affected."

The 43-year-old said she called customer service teams at Boost, who did not tell her about her phone being unable to make triple-0 calls, and Telstra refused to speak with her because she was not a customer.

"I don't really know what to do," she said.

"I don't think that I should have to shell out a couple of grand for a new phone when this one is working perfectly well and was never advertised as being anything otherwise.

"I've got a good job, I have money, but I don't have that sort of money just lying around, and I think the thing that got me the most from the telcos was that they just didn't care.

"There will be thousands of people who have to go and buy new phones and there's no minimal trade-in options because these phones apparently don't work anymore."

Are regulators cracking down on telcos and retailers?

The Australian Competition and Consumer Commission (ACCC) said it was monitoring phone retailers to make sure they did not sell devices that would not work now that the 3G network had been switched off.

The national consumer watchdog told the ABC in a statement that it worked with retailers prior to the shutdown to alert them of their legal requirements not to sell non-compatible mobile phones.

"Under the Australian Consumer Law, businesses must not mislead consumers, including by omitting information that is materially important to a consumer's decision," an ACCC spokesperson said.

"Businesses are also required to meet their consumer guarantees obligations under the Australian Consumer Law. This includes supplying products that are fit for purpose. The sale of a device that does not work post shutdown may not meet this guarantee.

"Whether any consumer guarantee or misleading conduct concerns arise will depend on the specific circumstances involved."

Under national communications law, telcos are required to "identify mobile phones unable to access triple-0, notify the user, provide assistance if necessary to access an alternative mobile phone, and cease providing service to the affected device".

"Providers will also be required to not provide service to a prospective customer seeking service with an affected mobile phone.

The new ACMA direction for the end of 3G also makes it a legal requirement for telcos to advise customers cut off from their services of "alternative mobile phones which are available, including low or no cost mobile phones, which are able to access the emergency call service".

The ABC has contacted ACMA for further comment.

What do the telcos say?

An Optus spokesperson told the ABC it had analysed tens of millions of call records to determine which devices used by its customers were no longer able to call triple-0.

The telco said it had a range of tests it used to determine the capabilities of phones, including checks on a handset's unique international mobile equipment identity (IMEI) number and correspondence with mobile manufacturers.

"The same model of a phone can be configured differently and in a way that is non-compliant depending on where the phone was purchased and configured," an Optus spokesperson said in a statement.

"Where there is any doubt about the ability of a device to access 000 — we are required by law to block. We have issued tens of millions of SMS, emails and messages to customers over many months to help customers make the transition.

"Customers have been provided with heavily discounted handsets and free handsets to ensure they are able to stay connected. Customer care teams are on hand to help provide customers with the best possible solutions."

Telstra also said it had checked billions of call records, industry records and user device behaviour data to determine which phones were no longer network-compatible.

"We are blocking devices in accordance with the new requirements under the amended ECS Determination, which affects less than 1 per cent of devices on our network," a Telstra spokesperson said.

"We are only blocking devices that don't meet emergency calling capabilities.

"Our advice to affected customers does not advise them where they should obtain a replacement device; we only advise them that they should replace their handset."