New warning over UK mobile network shutdown - are you affected?

Consumer comparison firm Uswitch told Express.co.uk that customers of O2 could be affected by the switch off if they are using older devices with a 3G connection. This extends to customers of Tesco Mobile, Giffgaff and Sky Mobile, providers that use O2’s network.

Uswitch said any worried mobile users should check if their devices are compatible with 4G or 5G networks, and claimed there are “4.3 million customers who could be using older 3G mobile devices”.

A Virgin Media O2 spokesperson pushed back on these claims to Express.co.uk and disputed the methodology of arriving at that figure, but did not provide a specific number of O2 customers who would be directly affected by the switch off. Virgin Media and O2 merged in 2021 but remain separate consumer brands.

Uswitch surveyed 2,000 UK adults, 875 of whom are on O2, Tesco Mobile, Giffgaff or Sky Mobile. 51 knew their phone was not 4G or 5G ready and 110 did not know. Uswitch then quantified these people as 5.5 percent of the overall sample size, and applied that to the adult UK population to reach 4.3 million.

The other three major UK mobile providers Vodafone, EE and Three, all completed their 3G network switch-offs in 2024. O2 is set to shutter its 3G service in 2025, though has not given a specific date.

“While the majority of customers do have a 4G or 5G compatible phone, there will still be a proportion of customers with older devices who will need to upgrade this year,” said Ernest Doku, telecoms expert at Uswitch.

“If you’re still using an older phone, you can check your device’s 4G and 5G compatibility by looking for ‘Network Mode’ or ‘Preferred Network’ under ‘Network’ or ‘Mobile Data’ in your Settings. If you see 4G or 5G, your phone is compatible.”

Switching off the 3G network might not be as disruptive as seems. Though phones used to solely use 3G to connect to mobile internet, most modern smartphones use 4G connections. The first iPhone to support 4G was the iPhone 5 in 2012, so an example of a smartphone with 3G internet is the iPhone 4S from 2011. This would be a model affected by this change.

However, the shutdown would not stop users of that device from making calls, as the UK’s mobile providers all still maintain their 2G networks for voice calls. Modern mobile phones increasingly use the 4G and 5G network for high-definition voice calls, but many can fall back to using 2G if there is only 2G signal available.

Most older 3G phones also behave in this way, to the detriment of call quality. You may also still be paying for a legacy 3G-only contract even though the phone you are using can connect to 4G or 5G. This is easily upgradeable with your mobile provider.

Much older devices, such as the classic Nokia 3310 from 2000, only ever used the 2G network for voice and text calls, so will continue to work. But in the coming years it is likely all the UK's 2G networks will also be retired as operators seek to move all customers to 4G and 5G.

“The switch off of the 3G network – agreed by industry and the government in 2021 and already completed by other network operators – will allow us to reallocate mobile spectrum to more efficient 4G and 5G services and improve customers’ experience with faster speeds, more reliable streaming and higher quality voice calls,” another Virgin Media O2 spokesperson told Express.co.uk.