Money expert Martin Lewis has issued a warning after the UK’s largest mobile network announced it is set to complete the shutdown of a major service after 22 years.

O2, now part of Virgin Media, has been shutting down its 3G services across the UK for months and is set to finish the shutdown early this year.

It means that customers still on the older 3G network will be forced to upgrade to a newer phone in order to keep getting access to data.

On the latest episode of The Martin Lewis Money Show Live on Tuesday, January 20, money expert Martin warned customers that they could still keep their existing phone but they won’t be able to access the internet, and their call quality is ‘likely to be worse.’

A viewer, Alan, sent a question to the show about the 3G switch off. He said: “My mum has a basic mobile phone. The network has messaged her about the 3G switch off, saying she needs a new 4G phone.

“Will she need to upgrade if she only calls and texts? She struggles with the technology, plus if she’s got no data, she can’t click links in scam texts.”

Martin then replied: “Alan, I totally understand and yes the 3G switch-off is imminent for everyone with very old phones.

“Now what will happen in most cases is the 3G will go off, you can’t get data or internet but you can still do calls and texts using the 2G network, but the call quality is likely to be worse when you do that. Unless you’re on Three, because Three doesn’t have a 2G network so it won’t work.

“Now some companies are giving vulnerable customers upgrades, but the safest thing to do and I totally get what you’re saying about your mum and her situation, there are phones like the Nokias that people give their 10-year-olds where they don’t want them to have a smartphone, the dumb phones if you like, which are in tune with a 4G phone but don’t have the data or things if you’re worried about your mum being scammed.

“See how her phone works, it should be OK just for calls and texts, but if not get her something like the Nokia.”

O2 said about its 3G switch-off: “Most of our 3G network has now been switched off across the UK, but some areas may still get a 3G signal during the early part of 2026. If you’re still using a 3G-only phone, you’ll need to upgrade to a 4G or 5G compatible device before the full switch off.

“3G has been superseded by 4G and 5G networks over recent years, with the 3G network carrying less and less traffic.

“By focusing our investment on 4G and 5G, we’ll be able to further expand and upgrade services, while being more energy efficient and better for the environment. Plus, it means you’ll be able to benefit from quicker download speeds and higher quality voice calls.”