Are your customers ready for the ISDN Switch-Off in 2025?

If not, now is the perfect time to provide a trusted solution to safeguard your clients’ connectivity and relieve any anxiety about what the future holds.


The world is evolving, and new technologies are beginning to weed out old systems and outdated infrastructure. The Public Switch Telephone Network (PSTN) is currently in place — but it’s ageing. This network supports several Openreach products that communication providers such as BT and TalkTalk sell to consumers, many of which benefit from Integrated Services Digital Network (ISDN) products.

Think of the PSTN as ‘traditional telephony’ via fixed, copper lines. Previously, we could only make telephone calls via these analogue lines while they represented the height of sophisticated technology. However, modern tech is evolving faster than ever, rendering the PSTN and ISDN services as old-fashioned in the wake of new digital communication. As a nation, we’re heavily reliant on a new digital network, and the requirement for the PSTN is becoming more obsolete each day.

In December 2025, these services will be switched off and replaced by IP technology. A new dawn of communication is coming.

Looking forward, it’ll be a priority for Openreach to provide a fibre-first network that’s shifting away from archaic, analogue telephone lines. Any businesses using analogue or ISDN phone number services will need to migrate over to VoIP or SIP instead — and it’s up to us to ensure they’re ready. As of September 2023, businesses will no longer be able to install or add lines to existing ISDN or PSTN networks, but a QUARTER OF UK BUSINESSES AREN’T EVEN AWARE THAT THE 2025 ISDN SWITCH-OFF IS TAKING PLACE.


Most telecoms resellers and wholesalers are live to the ISDN Switch-Off and understand the importance and the permanency of this change. This nationwide adjustment presents a staggering opportunity to upsell modern telecoms solutions that’ll give businesses peace of mind that they’re one step ahead of the switch-off, making them feel smug that they’ve got in there early.

Over the next four years, millions of consumers and businesses will need to upgrade their existing PBX hardware to handle the new technology required by the termination of analogue telephony. For many, this will look like switching to remote network management and integrating cloud-based communication software into their daily practices. Even now, businesses are being actively encouraged to migrate their call systems to VoIP.

The time to act is now. You can provide affordable, easy-to-integrate VoIP solutions to your customers before the whole country rushes to make the switch. Get the ball rolling and begin positioning yourself as your customers’ trusted telecoms provider that future-proofs their connectivity.


The widespread adoption of new technologies will be paramount for companies that don’t want to get left behind after the ISDN Switch-Off. Any businesses relying on ISDN or analogue phone services will need to swap to cloud-based PBX or FIBRE TO THE PREMISES— and they need to act now to ensure business continuity.

INVOSYS’ FTTP OFFERING is the perfect solution to help businesses safeguard their communication. FTTP takes the fibre optic connection directly from the local exchange into a business’ building, offering download speeds of up to 330Mbps and upload speeds of up to 50Mbps: a new era of telecommunications. It also ensures superfast performance with little-to-no dropouts thanks to the direct fibre connection.

What’s more, our all-new MS TEAMS DIRECT ROUTING SERVICE allows businesses to integrate their phone systems into Microsoft Teams. Not only does this facilitate user-friendly VoIP with a system that your customers are already familiar with, but it digitises telephony to provide the ultimate answer to the ISDN Switch-Off. Choosing this unique solution through Invosys means that our renowned Number Manager gets weaved into Teams, too.

One centralised platform for everything a business needs for seamless communication.

For companies looking to upgrade to hosted telephony without replacing their physical PBX hardware, we also offer an advanced SIP service. INVOSYS SIP gives your customers complete access to advanced VoIP features, enabling every step to take place within our Number Manager interface.

So, what better time to promote and sell the benefits of reliable, cloud-based servers and telecoms solutions to your customers? You can secure your clients’ continued business during the period of manic change, making them appealing offers to migrate their current setup to the new tech seamlessly.

We’re here to make this upsell as easy as possible. GET IN TOUCH WITH US TODAY to determine how we can support you and which products and solutions are suitable for your customers ahead of the PTSN switch-off.