BT’s fully digital phone services: what does the PSTN switch off mean if you or your customer use devices?

Homes and businesses use their phone lines for more than just making calls. There’s a wide range of equipment used for multiple solutions. If you provide or are involved in the provision of any equipment that works using our phone network, please read on. 

What's happening?

The Public Switch Telephone Network (PSTN) will close in December 2025.

By then, every phone line in the UK will have moved to a fully digital network that uses Internet Protocol (IP) across a fibre-based service.

This won’t just affect voice services; it may also mean you need to upgrade your broadband.

Any equipment that remains connected to the PSTN will stop working alarms, EPOS machines, door entry systems, CCTV, faxes, and so on.

The Integrated Services Digital Network (ISDN) will also stop working.

In readiness for this, Openreach are rolling out Fibre to the Cabinet (FTTC) and Fibre to the Premises (FTTP).

Why’s this happening?

Our current network is old and difficult to maintain. As an essentially 20th century technology, the PSTN is increasingly out of kilter with the demands of 21st century communications.

Traditional phone usage is changing everywhere as people switch to mobile and internet communications. We all expect much more from modern phone services than the traditional technologies can deliver. Digital is the answer.

At some point before 2025, customers will need to move from PSTN to the latest IP technology.

To help make that possible, Openreach is busy rolling out the full fibre network (fibre to the premises or FTTP) in phases across the UK. We’ll stop selling traditional phone lines in all exchange areas by September 2023.

What does this mean for lines with equipment other than phones connected to them?

Across BT our Consumer and Business customers, are likely to have a wide range of equipment which is connected to phone lines Including the examples above.

Any equipment connected to fixed phone lines will need to be IP compatible for it to continue working after 2025. This means anyone who supplies these products and services may need to carry out testing to make sure that their products and services will continue to work on an All-IP network.

Analogue Terminal Adaptors (ATA): These devices can be used to connect a traditional analogue device to a digital system to convert to IP. Consumer hubs provided have an Internal ATA.  An ATA is an interim solution and testing is essential. 

  • To get the best from the IP network, we recommend that your devices are upgraded to IP. If you get in touch with your device provider, they’ll be able to talk you through your options.

  • We want to work with you to ensure you’re aware of how the changes to our network will affect your existing products and services.

We have opened a BT funded, digital services lab at Adastral Park near Ipswich, our research and development site, for customers or vendors to come and test your services in this new digital world.

We also want to help you benefit from this opportunity to develop innovative new products and services. You can see a list of who's visited our lab on our page.

If you would like to book into our test labs (free of charge) to test your equipment please fill in the form to contact us and we’ll aim to get back to you within two working days.

We look forward to working with you.

User cases

Since 2018 we have been working with customers, manufacturers and industries to capture as much details as possible on how our customers use their telephone lines, these are categorised as user cases. We have approx. 200 cases identified, but we are sure there could potentially be more. If your user case is not listed above, please reach out to us so we can work with you to ensure your case is identified and solutions can be developed.  

Meet the team

Sodhi Dhillon

Device Partnerships Special Services

Sodhi is an experienced Telecoms professional with over 20 years of wide-ranging experience within the industry. He has a background in electronics and data communications enabling him to be well suited to help drive BT’s transformation to all IP.

Graduating from Kingston University with a 2:1 BEng hons degree in Electronics and Business he started his career developing payphones to use smartcard technology for a cashless society, well before smartphones even existed! At BT he has worked in a variety of roles developing world class products and solutions for both consumer and enterprise customers.

Sodhi lives in Surrey with his wife and young daughter, loves the outdoors and is a keen cyclist and runner. 


Graham Passmore

Industry Engagement Manager

Graham works in BT Business on the ALL IP Programme. His role is Migration enablement for Industries, Vendors and Manufacturers. His focus is around Industry and suppliers to ensure they are prepared for the withdrawal of the fixed line Telephony and the move to ALL IP.

Graham is an experienced telecoms professional and has worked in BT for over 24 years.

He has worked in numerous roles, all of which has kept him at the forefront of change within BT and telecoms industry, in both Voice and Broadband markets.
Prior to joining the ALL IP team he was a Product Manager for Analogue Telephone Adaptors (ATAs), working with industry to identify VoIP solutions for analogue devices.

Graham enjoys engaging with customers and identifying solutions for edge user cases with the shared goal of the 2025 switch off.

Graham Passmore