Jess speaking into headset at her desk in the Breakwater office.
Jess speaking into headset at her desk in the Breakwater office.

In January 2027, the Public Switch Telephone Network (PSTN) will be switched off.

At the same time, the Integrated Services Digital Network (ISDN) will also cease.

In its place, every phone line in the UK will move to Voice over Internet Protocol (VoIP) services.

The switch off was previously scheduled for December 2025, but has since been delayed to January 2027.

What is VoIP?

VoIP is an entirely digital service. Essentially, your voice communications are delivered over the internet. A VoIP system can be accessed from anywhere, as long as you are connected to the internet. This could be through home or office Wi-Fi, or using 4G or 5G.

Read more about the benefits of VoIP in our insight.

Past January 2027, existing copper and fibre optic cabling will still be there, but they’ll be used to carry digital signals instead.

What does this mean for your business telecoms?

Both home and business users will need to switch from PSTN to VoIP ahead of January 2027. And, of course, we don’t recommend leaving it until the last minute.

When the switch off happens, all equipment that uses the PSTN will stop working. This includes fax machines, door entry systems, CCTV, alarms, EPOS systems and more.

The transition from the PSTN to VoIP will all be dependant on your current setup. But this is something we’re ready to support you with. We’ve been transitioning businesses to VoIP systems for years and can recommend the best setup for your needs. Get in touch.

What is PSTN?

PSTN stands for Public Switch Telephone Network. This is a public telephone network that uses physical infrastructure, such as telephone poles and lines, to connect phone calls.

What is the difference between PSTN and VoIP?

PSTN uses a physical network to transmit voice data, whereas a VoIP systems transmits that data over the internet.

What are the benefits of a VoIP systems?

A VoIP system, in comparison to a tradition system, gives higher quality calls, cost savings, additional features and is easier to maintain and repair. Read more here.

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