A Major Shift In Business Communications
The UK is preparing for a significant change to its communications infrastructure. By January 2027, both the Public Switched Telephone Network (PSTN) and the Integrated Services Digital Network (ISDN) will be permanently switched off.
For decades, these systems provided the backbone of landline phone and early internet services. But now, with the rise of cloud computing, mobile connectivity, and digital-first operations, they are no longer fit for purpose.
This transition will affect millions of users, particularly small and medium-sized businesses that still rely on PSTN and ISDN for their day-to-day communication. If your business uses traditional phone lines or broadband running over copper wiring, this change will impact you.
What Are PSTN and ISDN?
The PSTN is the traditional circuit-switched telephone network, which has carried voice calls over copper wires since the 1800s. It has served homes and businesses for over a century.
ISDN, introduced in the late 1980s, allowed for voice and data transmission over the same line (a breakthrough at the time). Many businesses adopted ISDN for its improved call quality and early internet capabilities.
However, both systems depend on copper infrastructure that is now outdated, expensive to maintain, and unsuitable for today’s intensive needs like video conferencing, cloud telephony, and remote work.
Why Are PSTN and ISDN Being Switched Off?
The ISDN switch off is part of a broader digital transformation in the telecoms industry. Here’s why it’s happening:
Ageing infrastructure: The copper lines powering PSTN and ISDN are deteriorating and costly to repair.
Outdated technology: Legacy systems can’t keep up with modern communication tools and software.
Digital-first world: Businesses demand flexibility, mobility, and speed, all better delivered over digital networks.
That’s why providers are transitioning customers to an IP-Network- a fully digital system where voice and data travel over internet connections, not analogue lines.
What Will Replace PSTN and ISDN?
The shift to all-digital networks is built around two key technologies: VoIP and FTTP.
1. VoIP (Voice over Internet Protocol)
VoIP replaces traditional phone lines by using your internet connection to make and receive calls. Your voice is converted into digital packets and sent over the internet using an IP-Network.
VoIP is more than just a phone system- it’s a complete communications solution offering:
- Lower call costs, especially for international calls
- Flexibility to work from anywhere
- High-definition audio
- Features like voicemail-to-email, call forwarding, call recording, and more
- Easy integration with CRM systems and cloud-based apps
For small and medium businesses, VoIP is scalable and affordable, and a perfect replacement for fixed lines.
2. FTTP (Fibre to the Premises)
FTTP is a broadband solution that delivers fibre-optic connectivity directly into your building. Unlike traditional broadband, it doesn’t rely on copper — meaning faster and more reliable performance.
FTTP benefits include:
- Ultrafast download and upload speeds
- Minimal downtime and better stability
- Seamless performance for VoIP and video conferencing
- A future-proofed internet solution ready for digital growth
Together, VoIP and FTTP provide the reliable, cost-effective foundation for modern communication systems, and are essential for replacing PSTN and ISDN services.
The Switch Off Date Is Approaching- What Should You Do?
With the switch off date set for January 2027, now is the time to prepare. Here’s how to get started:
Audit your systems
Are you using PSTN or ISDN for phones, alarms, payment terminals, or fax machines?
Plan your migration
Explore VoIP and FTTP packages that match your business size and goals.
Immervox offer tailored migration packages, to help you transition to the best fit services.
Act early
Avoid disruption by starting the transition now.
Demand for installation and support will increase as the deadline approaches.
We’re Here to Help
As the PSTN and ISDN switch off nears, we’re helping small and medium businesses transition smoothly with:
- VoIP phone systems tailored to your team size and needs
- FTTP broadband for fast, stable connectivity
- End-to-end support to make your switch easy and stress-free
Don’t Wait — Future-Proof Your Business Today
The 2027 switch off is closer than you might think. Upgrading to VoIP and FTTP over an IP-Network isn’t just a requirement- it’s an opportunity to modernise how your business communicates.
Contact us today to explore flexible, cost-effective solutions that will keep your business secure and connected.
