PSTN Switch-Off
PSTN Switch-Off UK
The UK's copper telephone network (the PSTN) is being permanently switched off on 31 January 2027. Around 14 million homes and businesses are affected. If you've got a traditional landline, you need a replacement before that date.
| Question | Answer |
|---|---|
| What is the PSTN? | The UK's traditional copper telephone network. It's the infrastructure behind every conventional landline that's been in the ground for decades. |
| When does it switch off? | 31 January 2027 |
| Who is affected? | Anyone on a traditional copper landline with BT, Sky, TalkTalk, Virgin Media or similar. About 14 million UK homes and businesses in total. |
| What else stops working? | Fax machines, PSTN-connected alarm systems, older card payment terminals, and DECT base stations running off copper lines. |
| What does my provider do? | Most ISPs are migrating customers to digital voice (VoIP over broadband). You'll likely get a letter. Don't ignore it. |
| Can I keep my number? | Yes. Your existing 01, 02, or 03 number can be ported to a new service. Your customers won't notice any difference. |
Your two main options before 2027
What's right for you depends on how much you rely on your phone line and whether you can afford it going down.
Digital voice (VoIP)
The default replacement from most providers. Calls go over your broadband. Fine for most households, and it's usually included in your existing package. The catch: it stops working if your broadband goes down or the power goes off. Not great if calls are critical to your business.
Cost: typically included with your broadband.
Virtual landline (mobile network)
Your landline number routes to your mobile via the mobile network. No broadband needed, no router, no app. Works during power cuts, on the road, anywhere with a mobile signal. ONSIM has been running this since 2013 and it's never touched a copper wire.
Cost: from £5/month + VAT with ONSIM.
Why is it being switched off?
BT says modernisation. That's partly true. What doesn't get mentioned: Openreach expects to recover 200,000 tonnes of copper from the network through the 2030s, worth several billion pounds at current rates. Plus the cost of running thousands of telephone exchanges across the UK disappears overnight once the PSTN is gone.
We've written up the full picture, including the 3G switch-off parallel, if you want to understand what's actually driving this.
Don't leave it until 2027
ONSIM virtual landlines have nothing to do with BT's copper network and never have. Keep your number, take calls on your mobile, and pay less than your current line rental. Takes minutes to set up.