The short version
General information, not advice
- PSTN closing by 31 January 2027
- Copper lines replaced by digital networks
- Broadband required for landlines
- Fibre rollout expanding nationwide
- Vulnerable customer support available
The UK is moving from its old copper telephone networks to fully digital infrastructure. This guide sets out the PSTN switch-off timeline, the fibre rollout running alongside it, and what households and businesses need to prepare for.
What the PSTN switch-off is, and why it's happening
The Public Switched Telephone Network (PSTN) is the UK's copper-based telephone system. It has carried calls for decades, and it is now being retired across the country.
BT Group will retire the PSTN network by 31 January 2027, and Openreach confirmed on 24 September 2026 that this date has not changed. Traditional analogue landlines are being replaced by digital Voice over Internet Protocol (VoIP) services that run over broadband. The copper network is ageing and increasingly unreliable, expensive to maintain, and never built for modern digital traffic, which limits its speed and scope. Moving to digital lets providers improve reliability, extend fibre coverage, cut fault rates and modernise the network. This is a nationwide migration led by Openreach and the telecom providers, not something individual customers opt into.
Fibre rollout
Alongside the PSTN retirement, the UK is rapidly building out full-fibre broadband (FTTP). Full fibre replaces copper entirely, gives steadier speeds, supports symmetrical upload and download, and is far less affected by distance from the cabinet. The government's target is nationwide gigabit-capable coverage. Not everywhere has full fibre yet, so some households will move onto digital voice while still running over FTTC or another hybrid network.
What changes for households
Under the digital system your phone plugs into your broadband router rather than a wall socket, calls travel over your internet connection, and you need broadband active for the landline to work. The catch is power. Old copper landlines kept working in a power cut because the line carried its own power; a digital service does not, unless there's a battery backup. If you depend on your landline, check whether your provider offers a battery backup, ask about a mobile fallback, and confirm how emergency calls hold up if the power goes.
Alarms, telecare and health monitoring
Older burglar alarms, lift emergency lines, telecare pendants and medical alert systems may not work properly once the PSTN is gone. Contact your alarm or telecare provider, confirm the device works on a digital network, and upgrade the equipment if it doesn't. This matters most in households that rely on those systems for safety.
What it means for businesses
Businesses need to plan for phone system upgrades, VoIP hardware, broadband resilience and backup connectivity. Analogue lines running card machines, fax or CCTV connections may need replacing. The practical step is to audit every analogue line, confirm what's compatible with digital, and consider a backup broadband line or 4G failover.
What to do now
Ask your provider about its migration plans, confirm whether your router supports digital voice, check what support is available for vulnerable users, and review any alarm or monitoring systems. If you run a business, draw up a migration plan for the lines you depend on.
Source: Openreach, "Openreach to protect broadband connections as PSTN closure approaches", 24 September 2026, checked 4 October 2026.
Key takeaways
- Copper lines are being retired
- Digital broadband becomes essential
- Alarm systems may need upgrades
- Vulnerable users can request support
- Check provider migration plans
Common questions
Will my landline stop working?
Traditional analogue services will be replaced with digital alternatives.
Do I need fibre?
Not necessarily, but digital broadband will be required for voice services.
Will I lose my landline number?
No. Your number should transfer to the digital service.
What happens in a power cut?
Calls may not work unless you have battery backup or mobile fallback.
Do I need fibre broadband?
Not necessarily — digital voice can work over FTTC — but full fibre improves reliability.
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