BT switch off: what to know

The UK’s analogue phone network is closing. Here’s what you need to know.

The UK’s traditional phone network (PSTN and ISDN) is being switched off. The final national deadline is 31 January 2027.

After this, any service still running on analogue lines will stop working. This change affects far more than desk phones. Many sites still have alarms, lifts, payment terminals, door access, telemetry, and other systems running on legacy lines.

To avoid disruption, migrations need to be completed well before the deadline.

Providers, vendors and engineers will all hit capacity as the date approaches. Over the next few months, we’ll share short updates covering what’s changing, who is affected, and what action to take. If you want to get ahead now, we can audit your sites and map out a clear migration plan.

We’ll take care of:

• Line/device audit, migration plan and scheduling

• Number porting and communication routing changes

• Router/ATA install, QoS, and battery/4G failover options

• Vendor coordination (alarms/lifts/EPOS) and post-cutover testing

• Staff guidance and simple ‘what’s changing’

Digital alternatives like VoIP and cloud-based phone systems are already available, often more reliable, and more cost-effective.

Please get in touch with us if you're still on a legacy network – or even if you're not sure – and we can review your current set-up.