The UK’s legacy phone network is nearing its final chapter. Openreach is preparing to close the PSTN by January 2027. The shift affects homes, shops, offices, alarms, payment terminals, and telecare services.
The main task now is not the technology itself. It is finding the remaining users and moving them safely.
James Lilley, who leads the Openreach migration team, says the scale has changed sharply. “Today, fewer than 1.5 million remain”, Lilley tells Mobile Europe.
The company started the closure process around 2017. At that time, about 16 or 17 million customers still used the network. Most have now moved to digital alternatives.
However, the final users are often the most complex. Many businesses do not know what still depends on old phone lines. A single line may support a fax machine, alarm system, or card terminal.
Lilley highlights that hidden dependency clearly. “You’ve got lots of different things potentially connected to phone lines, like fax machines, alarm lines and payment terminals – things that you’ll see in typical businesses that not many know they are connected to the telephone network,” he says.
This creates operational risk for companies. A rushed migration can disrupt payments, security, or emergency systems. Yet delay can also increase costs and service exposure.
Openreach says prices for legacy services have already increased. Another rise is due in October. That makes the older network less attractive for many companies.
The newer fibre-based infrastructure offers stronger reliability and lower energy use. It also supports modern broadband and digital voice services more easily. For VoIP engineers, the move confirms the UK’s clear path away from copper.
Still, Openreach wants to avoid panic around January 2027. Lilley says there will not be a sudden nationwide shutdown. “There isn’t a scenario where there’s going to be a mass ceasing of customer services, and lots of things stop working in January 2027,” he says.
Even so, businesses should not wait. “If customers don’t move things, then there is ultimately a risk of disruption,” he adds.
Openreach has also created fallback options for late movers. Lilley calls this a “lifeboat solution”. But it may include downtime and disruption. Customers will still need to leave the old system.
Vulnerable users remain a major focus. Telecare devices can rely on traditional phone lines. Engineers can visit homes, test equipment, migrate the service, and test it again.
For some landline-only users, Openreach can migrate services in the background. “We’ve developed solutions where we can actually just migrate the customer in the background,” Lilley adds.
The PSTN closure is also part of a wider fibre strategy. Openreach has invested £15 billion in fibre upgrades. It expects full-fibre availability to reach 25 million UK premises by late 2026.
The next phase will target the copper network itself. “That’s really the big transformation the whole UK telecom industry is going through at the moment, as we move off copper onto fibre,” Lilley concludes.
