March 6, 2023

The Big PSTN and ISDN switch off – what does it mean for you?

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The Big PSTN and ISDN switch off – what does it mean for you?

In December 2025, the BT Openreach Public Switch Telephone Network (PSTN) will be switched off. This means that the old analogue network that has been used since the last century will no longer be available. BT Openreach has decided to stop investing in a technology that can’t fulfil the requirements of a modern-day business as it struggles to support the speed, scalability, and method of communication that business use today.

PSTN and ISDN switch off

So, by 2025, every phone line in the UK will need to move to a fully digital network that uses Internet Protocol (IP) across a fibre-based service. Do you have a plan for your business? If not, then read on for our advice on how you can prepare now for the PSTN and ISDN switch-off.

What is happening and when?

PSTN and ISDN switch off timeline

Is it just phone lines which will be impacted?

No, it’s not just phone services which need to be considered. It’s everything that currently uses a phone network, this might include but not limited to:

  • Alarm lines
  • CCTV
  • Door entry systems
  • EPOS and card machines
  • Remote telemetry systems
  • Fax machines
  • Lift alarms

What are my options?

All businesses currently using PSTN and ISDN services will need to migrate to a new service as the current infrastructure will simply stop working.
Organisations need to plan how to mitigate the impact of this change on their communication strategy: how will they communicate internally and externally, with clients and service users, and suppliers and partners?

This provides an ideal opportunity for organisations to streamline operations, drive cost efficiencies and improve customer service.

Trustmarque have a long pedigree of consulting and delivering voice services to meet our customers’ demands. The services delivered include:

Trustmarque works with a range of partners to deliver choices accompanied by professional services to help you select the right solution and implement it successfully.

How can Trustmarque help?

Our experienced consultants will work with you to plan the most effective deployment to meet your organisation’s needs. We provide the following services to ensure a smooth transition away from your legacy PSTN and ISDN network:

  • End-to-end consult, deploy and migrate, onboard, and support professional services
  • AutoDiscovery service to accelerate and de-risk transition from your current technology
  • Implementation and staff training services to ensure rapid user adoption and return on investment

For many organisations the BT Openreach PTSN and ISDN switch-off provides a long overdue opportunity to focus on realising the benefits of a modern telephony infrastructure:

  • Cost control and predictability
  • Scalability
  • Business continuity
  • Operational efficiency

To realise the benefits in a short space of time, Trustmarque’s VoIP services can quickly help you implement a digital solution.

Please contact your Trustmarque Account Manager or complete the form below and you can start your transition away from PSTN and ISDN.


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