Millions of O2 customers across the UK have been issued an urgent warning to upgrade their mobile devices or risk being cut off from the internet. The country's largest mobile provider has confirmed it will completely shut down its ageing 3G network in 2026, branding the technology a relic of the past.
The Countdown to the 3G Switch-Off
O2 has stated that the decommissioning of its 3G services is imminent, with the final masts set to go dark next year. The move reflects a dramatic shift in how we use mobile data; today, a mere two percent of O2's traffic runs on the 3G network. The provider says this older technology can no longer meet modern demands for speed and reliability, which are now served by advanced 4G and 5G infrastructure.
Jeanie York, Chief Technology Officer at Virgin Media O2, explained the decision. "We're now more connected than ever thanks to significant investment in faster, more reliable 4G and 5G networks," she said. "As a result, 3G has become a relic of a bygone era." She confirmed that while a 3G signal might briefly appear in some locations in early 2026, the network will soon be fully and permanently shut down.
Who is Affected and What You Need to Do
This shutdown will only impact users who still own and use older handsets that rely solely on 3G connectivity. These customers are being urged by O2 to upgrade to a 4G or 5G-enabled device "as soon as possible". The network has stated that affected users should have already been contacted directly with details about their upgrade options.
Failure to act means those with 3G-only devices will lose access to mobile internet services, though voice calls and texts over 2G will remain available for now. O2's rivals, including Vodafone, EE, and Three, have already phased out their own 3G networks in recent years, making this an industry-wide transition.
Benefits of the Network Evolution
Decommissioning the outdated 3G network is not just about retiring old tech; it brings tangible benefits for the vast majority of users. The valuable radio spectrum freed up by the switch-off will be reallocated to bolster O2's 4G and 5G networks. This process will enhance data speeds, improve call reliability, and expand the geographic coverage of the newer, faster services.
The transition has been in planning for years, with extensive testing carried out throughout 2025 to ensure a smooth process. The evolution from 3G, which first brought reliable mobile internet in the early 2000s, to 4G and now 5G represents a massive leap in capability, enabling everything from high-definition video streaming to supporting the Internet of Things.
For any customer uncertain about their device's capabilities, O2 advises checking their phone's settings or contacting customer service directly. The message is clear: the 3G sunset is coming, and preparation is essential to stay connected.
