The PSTN switch-off: why it’s happening and what action you need to take.

Published by Phoebe Oon on March 11, 2024

By Kim Holder, Director Voice & UC and Network Sales Specialist at Colt

In December 2025, BT Openreach will turn off the Public Switched Telephone Network (PSTN).  This means that all PSTN phone lines will need to move to Voice over IP (VoIP) services instead. VoIP is a technology that uses an internet connection to carry voice calls.


What is PSTN and why is it being replaced?

PSTN is the traditional circuit-switched telephone network, which is based on copper wires. It will be replaced by a fully IP network built on fibre.  BT is making this change because the PSTN can’t support the demands of modern communications.


How do I replace my PSTN services? 

To meet the PSTN switch-off deadline, organisations need to be considering the options for replacing these services with VoIP.  There are lots of choices, and it’s important to choose a service that provides you with the quality and simplicity you need to get on with the day-to-day activities that really matter to your organisation.


Is migrating to an IP solution difficult? 

Migrating to the latest communication technologies can seem daunting – but it doesn’t have to be that way. Colt has the expertise and resources to help you move to highly reliable, high-performance IP service quickly and easily, without disruption.  We can also help you build the foundation for fully integrated voice and Unified Communications.

Our voice and Unified Communications solutions are designed to help your employees work at their best, connecting people with modernised, easy-to-use tools and services that are simple and secure. Our experts work closely with you to establish your specific business needs and identify the solution that works best for you.  Colt Voice and Unified Communications solutions offer superb reliability and excellent value for money, which can provide reduction in TCO and unplanned downtime1.


Are there benefits from using a single provider?

Using one provider for all your voice and Unified Communications services significantly reduces the time needed to manage suppliers and improves performance and troubleshooting.  Using a single provider boosts employee productivity and can cut operational costs.

To find out how Colt can help you turn the PSTN switch-off into an opportunity for greater productivity, simplicity, reliability and cost savings, contact us on here.

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