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The PSTN and ISDN switch-off: what it means for you | BT Business

The PSTN and ISDN switch-off: what it means for you

What's happening?

The Public Switch Telephone Network (PSTN) will close by 2027.

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 currently uses 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.

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.

What does this mean for me?

At some point before 2027, you’ll 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.

Openreach’s roadmap to a full fibre network

To make the transition as seamless as possible, Openreach is enabling full fibre exchanges in a phased approach across the UK. Openreach will add new exchanges to the rollout plan each quarter.

You can read more about the switch-off on Openreach’s website. In the Resources section, you can download the list of exchanges Openreach has announced so far.

When will my area be full fibre-enabled?

You can find out if your address has been full fibre-enabled by clicking on the Check availability button at What’s available to me now?


The PSTN stop sell

The PSTN stop sell means you’ll not be able to purchase legacy voice or broadband services. The PSTN stop sell is a major milestone in the UK’s transition to more advanced and efficient communication technologies. By upgrading to IP solutions, your business can benefit from enhanced features, improved scalability, and cost savings.

It's important to plan ahead and begin exploring IP alternatives sooner rather than later. Our team will guide you through the transition process to make sure you have a seamless migration.

Need more help? Take a look at these frequently asked questions:

How will the PSTN stop sell affect my existing analogue phone lines?

All your existing services will continue to work as they do today. The PSTN stop sell means that new activations or changes to analogue phone lines won’t be available. But you can still leverage your existing infrastructure and smoothly transition to IP solutions without disruptions.

Will I be able to add or make changes to my current PSTN phone lines after the stop sell?

You won’t be able to add any new lines, or additional channels to an existing ISDN. After the PSTN stop sell, some changes might be available. You’ll need to call us on 0800 800 152 to discuss your requirements or to understand how by upgrading to an IP voice solution, you’ll gain access to a wider range of features and future-proof your communications, ensuring flexibility and growth opportunities.

What's available to replace PSTN for my business communications?

We have a range of different IP based options to provide the best fit for your business. They leverage internet connectivity, providing cost savings, advanced features, scalability, and seamless integration with other business tools. Find out more on our IP Technology page.

What's Voice over IP (VoIP) and how's it different from traditional phone services?

VoIP converts voice signals into data packets transmitted over the internet, eliminating the need for traditional phone lines. It offers high-quality voice calls, improved flexibility, cost savings, and additional features like voicemail-to-email, video conferencing, and much more.

Will moving to an IP-based solution require significant changes to my current phone system setup?

Thanks to our wide portfolio of options the upgrade to an IP alternative can be tailored to your business' specific needs. Our team will work closely with you to make sure you have a smooth migration, adapting your existing setup and preserving your valuable investments.

How will the quality of calls be affected when moving from PSTN to IP alternatives?

IP alternatives provide excellent call quality, often surpassing that of traditional analogue systems. With the right setup, network optimization, and bandwidth considerations, you can enjoy clear and reliable communications.

Can I keep my existing phone numbers when switching to an IP-based solution?

Yes, you can keep your current phone numbers when transitioning to IP solutions. What’s more, you can take those numbers with you wherever you move in the future as they’ll no longer be tied to specific areas. Our team will guide you through the number porting process, making sure you have a seamless transition without losing important contacts.

Are there any specific requirements or infrastructure changes needed to switch to IP alternatives?

The requirements might vary depending on your current setup. In most cases, the transition to IP alternatives is very straightforward. If you have any specialist devices connected to your phone lines (such as bells, alarms, card payment devices) then you may need to upgrade these to an IP equivalent, in some cases these devices can be supported with an ATA (analogue terminal adaptor), speak to one of our team today who can help guide you through the requirements.

How secure are IP-based communication systems compared to traditional PSTN lines?

We take security seriously. We employ more than 3,000 cyber-security experts, who protect and monitor our networks 24/7. And we build end-to-end security into every one of our solutions.

Will the cost of my phone services change with IP alternatives?

The shift to IP often brings cost savings. With options for inclusive calls, free devices and no maintenance costs businesses can experience significant savings compared to traditional voice services.

What extra features and capabilities can IP solutions offer?

IP alternatives provide an array of advanced features such as auto-attendants, call forwarding, call recording, virtual meetings, instant messaging, and integration with collaboration tools. These features enhance productivity and streamline your communications.

Can IP-based solutions integrate with other communication tools and software we currently use?

Absolutely! IP alternatives offer seamless integration with various communication tools and software, including customer relationship management (CRM) systems, email clients, calendars, and team collaboration platforms, optimizing efficiency and workflow.

Are there any limitations or potential challenges in moving from PSTN to IP?

While every transition has its considerations, our team is well-equipped to address any potential challenges. We’ll make sure there’s minimal disruptions to your business operations and provide comprehensive support during the transition period.

Any questions?

Call us on 0800 028 2075. We’re available 8am–6pm, Monday to Friday.

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