What is Happening?

The infrastructure that makes everything work, from the copper cables underground to the telephone cables strung above us will no longer be in use from 2025 and the process of doing this has already begun.

This is called the Public Switched Telephone Network (PSTN) and Integrated Services Digital Network (ISDN) switch off.

With the increasing demands and evolution of modern communications, everyone requires more than the traditional telephone systems were created to deliver.

The 2025 PSTN Switch Off doesn’t just affect the business world. All recreational and residential services will also follow suit. In the move to embrace fully internet-based communications, the UK’s telephone network provider is phasing out the PSTN (Public Switched Telephone Network) at the end of 2025. From October 2021, a programme of ‘Stop-Sell’ was put in place. ‘Stop-Sell’ has restricted both residents and businesses from purchasing new PSTN-based phone services such as ISDN (Integrated Services Digital Network), as well as ending all renewals of their existing legacy services.

How will telephony be delivered going forward?

Voice over Internet Protocol (VoIP) uses a companys’ existing internet connection to transmit voice calls.

An example of this is the mobile application WhatsApp. Although VoIP relies on the quality of the internet connection to guarantee stable calls, nowadays, the speed of most broadband connections is fast enough to negate any issues around call quality.

Your physical infrastructure will not be affected if you are simply migrating to a VoIP system – your telephone will be connected directly to your router.

Why should I change?

VoIP is a much better alternative to traditional landlines. This technology offers many opportunities and benefits for your business.

Change brings opportunities

The PSTN Switch Off is a great chance for small businesses to improve their customer experience and efficiency. Calls will also be clearer and you will have the ability to make multiple calls simultaneously.

Changes can be implemented quicker and easier on a VoIP system for example call routing and diverts, and there is a greater choice of hardware and equipment available.

One of the advantages to having a VoIP telephone system instead of the existing landline is the Over-the-Top (OTT) services that use the internet provision. OTT services refer to any streaming service that delivers content over the VoIP service, as it is delivered “over the top” of another provision, hence the acronym.

In previous years, a consumer would take out a SKY, Virgin or other cable subscription and their cable TV provider would be responsible for the supply and availability of programming. In the modern era, users can sign up for services like Netflix or Spotify and access their offerings over the internet.

This gives users more flexibility when making and receiving calls. It can also be used on a variety of devices – from desk phones to mobiles, tablets and computers.
From the one-man-band struggling to stay on top of customer calls, to the local hairdresser or restaurant that wants to improve customer experience (or more simply, increase bookings) but don’t quite know how.

In either scenario, the problem starts and ends with their telephony system. Phone numbers are central to the correct functioning of our local economy, yet over 3 million still rely on obsolete phone systems to deal with their customers. VoIP can solve all that and more, with minimal disruption to the business. Similar to WhatsApp, some VoIP solutions even come in the form of a simple mobile application. This is extremely beneficial to a busy company as mobile apps update automatically, removing any need for technical expertise.

How will my business be affected?

Traditional telephone lines are often used for more than just telephone calls. Check all of your devices to see if they are currently using PSTN. Devices include door entry systems, alarms, lift emergency lines, payment terminals and cash machines. You can either upgrade your equipment or an adaptor can be supplied to make the device compatible with VoIP. This process can start anytime from now until 2025 but it’s best to switch over sooner rather than later.

Digital cloud-based telephone systems are not only better than the old telephone systems as they are 20th century and more advanced technology, they are also more cost effective.

By using a VoIP telephone system, you will be able to make and receive calls on numerous devices, wherever you may be, using the same telephone number. VoIP telephone systems allow you to work from anywhere in the world, accessing all business applications and systems such as video chat and calls, enabling you to run your business ‘as normal.’

Embrace the future

The PSTN Switch Off is inevitable and the only way forward is to switch to a VoIP solution. The move to all Internet Protocol (IP) is underway and as early as 2023, businesses will no longer be able to purchase the older services.

The longer a business waits to make the move, the harder it’s going to be to find the appropriate solutions for their needs. Thousands of businesses have already moved to a VoIP solution. Smaller businesses finally have the chance to compete with those bigger enterprises, without breaking the bank and with a solution that will scale and grow as they do.

The PSTN Switch Off and the subsequent move to all IP is a true opportunity for the businesses in your area to take control of their customer interactions and eliminate any challenges they’ve been facing so far.

Now is the time to embrace the technology of the future.


In November 2017, BT Openreach announces its intention to switch off the PSTN in 2025


In June 2019 Trial sites in Salisbury and Midenhall announced & Openreach strengthens fibre network.


In December 2020, Openreach starts the process of retiring PSTN & ISDN. “Stop-Sell” notice of legacy services in Salisbury trial site.


In May 2021, “Stop-Sell” notice of legacy services in Midenhall trial site.


In December 2022, Salisbury and Midenhall trial sites – Withdrawal of legacy products & services.


In September 2023, “Stop-Sell” notice issued. No new line installations, line conversions or ISDN Channels.


In December 2025, PSTN & ISDN will be Switched Off.