The UK PSTN and ISDN switch-off is BT Openreach’s permanent retirement of the legacy network, scheduled for on 31 January 2027. After this date, traditional landlines, ISDN circuits, and devices including lift emergency alarms, intruder alarms, EPOS payment terminals, and legacy broadband will cease functioning. Businesses must migrate to Internet Protocol (IP)-based services, such as VoIP
Openreach is shutting down their analogue services, also known as the Wholesale Line Rental (WLR) network which is what traditional lines and old networks rely on. Some of the common services being shut down is:
This change will take place by 31st January 2027. Often, the switch is confused to be just phone lines, but in actuality, it includes every service or business infrastructure that still uses the WLR network. Which, while it does include landlines, also includes broadband connections, CCTV, alarms, payment terminals, lifts, and more.
In short, the cost, the reliability, and the fragility of the analogue network are just some of the reasons that this change is taking place.
According to Openreach, the hardware can’t keep up with modern requirements, becoming increasingly “fragile and prone to failure.” To support this, Ofcom reports a sharp 45% rise in PSTN resilience incidents in their 2024 Connected Nations report.
The global market is changing quickly, in fact Estonia and Netherlands have already switched from PSTN networks while Germany, Japan, and Sweden are making the shift already and ahead of the UK market in making the change.
The prices for the legacy lines are now increasing, “a 20% rise on 1 April, a further 40% on 1 July, and a final 40% increase on 1 October”. This practically doubles the price from what it was in 2025.
Businesses will have to make the leap to switch to a fully digital service that uses IP (Internet Protocol) technology, so VoIP phone systems and internet-based services.
PSTN was built in the 20th century and the traditional technology is struggling to deliver on more modern demands which require more reliability and security.
It’s better to make the switch earlier than later, it allows you and your team to get accustomed to the new systems and means you avoid the digital rush that will no doubt happen closer to the hard cut-off deadline in 2027.
Forward-thinking organisations view the switch-off as an opportunity to modernise the experience and infrastructure. Moving from those legacy communication channels offers immediate advantages:
Perform an Asset Audit: Inventory every physical line, phone extension, alarm, lift auto-dialler, and payment terminal across all sites.
Verify Broadband Capabilities: Test the bandwidth, latency, and stability. Ensure network capacity can support concurrent HD VoIP calls.
Assess Critical Dependencies: Contact alarm suppliers, lift maintenance providers, and merchant acquirers to confirm compatibility.
Select the Right VoIP/UCaaS Partner: Choose a reputable provider offering number porting, robust SLAs, call recording, and seamless CRM integrations.
Plan Number Porting Early: Initiate number porting requests early to avoid losing long-standing business
telephone numbers during migration.
Execute Staff Training & Testing: Conduct testing phases and train staff on applications before pulling the plug on analogue lines.
Delaying action poses extreme risks of service blackout, critical equipment failure, and revenue disruption,
proactive businesses can leverage this shift to build a faster, more resilient, and customer-centric operation.
If this all sounds a little complicated or time consuming, you can get in contact with us at Collaborative IT and we’ll support and help you through this change – don’t hesitate to give us a call or send us an email. With years in the industry, we provide IT support, consultancy, VoIP and more, to companies big and small.
Need IT Support now? We can help. Contact us below, call us on 01844 318131 or email ask@colit.co.uk.
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