Significant changes are on the horizon for UK telephony and communications.
You have likely heard of the impending PSTN Switch-Off, which will take effect in January 2027. On this date, BT will permanently shut off the UK’s traditional Public Switched Telephone Network (PSTN), which comprises all copper phone lines and services connected to them: landline phones, fax machines, alarms, payment terminals, and some broadband connections across the country.
While this might sound daunting, it isn’t just the end of something old—it’s also the beginning of something newer and better. The UK is embracing a full Digital Switch-On, moving all phone services to internet-based services like VoIP (Voice Over Internet Protocol), marking a significant shift toward faster, smarter, and more flexible infrastructure to support business communications across the UK.
This blog explores the PSTN Switch-Off and why you must prepare for the impending shift to ensure a smooth transition.
What is the PSTN Switch-Off?
The Public Switched Telephone Network—shortened as PSTN—is a historic, copper-based telephone network that has been in use since the 1800s. It powers traditional phone numbers, landlines, fax machines, broadband connections, and even payment terminals to connect and operate.
The telephone network also includes ISDN (Integrated Services Digital Network), a digital upgrade introduced in the 1980s that allowed businesses to make multiple concurrent calls over a single line. However, these are now outdated and too expensive to maintain long-term. More importantly, they can’t keep up with today’s digital demands for speed, flexibility, and bandwidth.
Over time, the PSTN has become increasingly outdated and expensive to maintain. Specifically, it no longer meets the modern-day demands of businesses that require flexible, data-rich communication. As a result, Openreach has announced the complete shutdown of PSTN and ISDN services by December 2027, which comprise analogue and digital phone lines connected through copper wires.
In its place will be fully digital communication using internet-based technologies like VoIP (Voice over Internet Protocol), full-fibre broadband, FTTP (Fibre to the Premises), SOGEA (Single Order Generic Ethernet Access), high-speed Ethernet, and cloud-hosted phone systems.
What devices will be affected?
Contrary to popular belief, the switch-off doesn’t just affect landline phones. Many business-critical systems still depend on PSTN lines, such as:
- Desk phones using analogue or ISDN connections
- Fax machines
- Door entry and security systems
- Alarm lines and fire panels
- Payment terminals and PDQs
- Select broadband services
- Emergency call systems
- Messaging and paging services
If these systems are part of your daily operations, they will cease functioning after the switch-off date. Upgrading in time ensures you avoid this entirely.
Why small businesses can’t afford to wait
According to BT’s research, 22% of small businesses still identify as using ‘analogue’ operations, meaning they rely on the PSTN daily. Nearly a quarter of companies – just over a million estimated in the UK – risk significant disruption.
The longer businesses delay the switch, the higher the risk and the more expensive and disruptive the transition will become. Potential issues include:
- Missed customer calls due to phone outages
- Lost sales if payment systems or mobile phones stop working
- Security concerns from unsupported alarm systems or door entry systems
- Limited support as suppliers and telecom providers become inundated closer to the December 2027 deadline
- Unanticipated downtime from last-minute or poorly planned upgrades
Even one day of downtime or disruption can cause a damaging ripple effect for small businesses. Upgrading as soon as possible allows you to plan appropriately, test and bolster new systems, and avoid unnecessary stress.
Why it isn’t just a switch-off – it’s a switch-on
While it’s easy to focus on the switch-off and the associated disruption, the bigger picture lies in the benefits of switching on the replacement infrastructure. Moving to all-digital systems isn’t just a technical update—it’s an opportunity to future-proof your business, making it more agile, efficient, and competitive.
The digital switch-on unlocks benefits, including:
- Smarter communication – VoIP enables features like call forwarding, voicemail-to-email, video calling, auto-attendants, and mobile access – all managed centrally through the cloud, giving you and your team more flexibility and control.
- Lower costs – Digital communication systems often have lower maintenance fees and more flexible pricing structures, helping customers save money as they transition to digital solutions.
- Better scalability – As your business grows, you can easily add new locations and users without investing in additional hardware.
- Greater flexibility – Cloud-based systems allow your team to stay connected and productive from anywhere, regardless of location, and even during outages or emergencies.
- More bandwidth and better performance – Transitioning to FTTP, SOGEA, or Ethernet ensures your business meets the bandwidth requirements for video conferencing, real-time collaboration, and cloud tools.
The future is digital – don’t get left behind!
The PSTN Switch-Off is coming, and the consequences could be severe for businesses that prolong the transition.
With the proper support, it’s a chance to embrace newer, better technology, work more efficiently, and prepare your business for long-term success.
Ready to switch on? At Stream, we offer an extensive suite of Unified Communications (UC) solutions designed to future-proof your business in the wake of infrastructure changes.
View our range of solutions here and contact us to take the first steps towards digital-ready communications.
We’ve been a leader in all things telecommunications for nearly two decades. Let’s make the switch-on work for your business.