ISDN switch off

What is the ISDN switch off?

Introduced in 1986, the ISDN, or Integrated Services Digital Network, is a telephone network configuration that uses digital transmission to make voice calls, video calls and transmit data (and other network services) via the circuits of the Public Switched Telephone Network, or PSTN. Both the PSTN and ISDN are currently scheduled for decommissioning in 2027.

The ISDN switch off is a nationwide analogue to digital switch that will see the old copper phone network turned off and the country switched to fibre in 2027.

For businesses, this means that you will have to implement an alternative to ISDN lines (and any hardware that uses them). So, it’s time to upgrade your telecoms and connectivity to ensure your business stays in touch and ready for an all-digital future!

What is the difference between ISDN and PSTN?

The ISDN switch off and the PSTN switch off are the same ‘event’ but refer to two different networks that transfer voice and data over the UK’s phone lines and that will be switched off at the same time. The PSTN is a ‘circuit-switched’ analogue system requiring an operator, a telephone exchange and a pair of overhead wires to function. The ISDN is a digital-based network, offering end-to-end connection to allow for telephone calls and other non-voice services.

When is the ISDN switch off happening?

The ISDN switch off is happening in 2027 and aims to be completed by the end of December that year. You will be able to purchase new ISDN lines until September 2023. After that, no new ISDN lines will be installed or added. There will be a ‘forced migration’ phase between May 2024 and January 2027 (the nationwide stop-sells). Be aware that different areas may have different stop-sell dates. Businesses will benefit from switching over their infrastructure early, as they will avoid the risk of costly disruptions.

How will the ISDN switch off affect me?

The communications (and some security) infrastructure will be affected by the ISDN switch off. In short, any hardware that is not VoIP compatible, or uses your ISDN phone line, will not work after the switch. If these changes are not made in time, businesses with redundant systems will incur costly expenses and disruptions to their networks.

What do I need to do? What are the alternatives to ISDN?

As traditional ISDN lines can’t meet current demands, your ISDN communications infrastructure will need to be replaced with technology that uses internet protocol (IP) and runs on the new fibre-based network. This means that you will need to upgrade to VoIP (Voice over Internet Protocol or IP telephony) technologies, which transform analogue calls into packets of data and are delivered over IP networks. This can be achieved by using SIP (Session Initiation Protocol) trunking, which allows you to make calls using a data connection, or by switching to a fully hosted cloud system.

Focus Group is well placed to support your business through this transition, at no additional cost. We’ll ensure you have everything you need well ahead of 2027, from a VoIP phone network to the SIP trunking system, leaving you free to focus on the important stuff like growing your business.