ISDN SWITCH OFF:
WHAT IS IT?

The UK’s ISDN switch-off is already underway, and it means your current phone system will soon stop working.

You have until 31st January 2027 before the switch off impacts you and your customers.

Openreach are retiring ISDN lines, and our expertise can replace them with faster, more flexible broadband-based (VoIP) technology. The result is clearer calls, better features, and a system built for the modern-era.

If you’re still using analogue lines (ISDN), now’s the time to act. Find out what the ISDN switch-off means for your business and how to upgrade without disruption.

Business Phone System • Broadband • Mobiles • IT Services

blueprint of services impacted by isdn switch off

TIME LEFT TO SWITCH:

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WHAT IS THE ISDN SWITCH OFF?

The ISDN switch-off refers to the process of discontinuing the use and support of ISDN technology by telecommunications companies in favour of more modern and advanced technologies powered by broadband internet.

Many UK businesses are still using the ISDN system and will require upgrade to a newer system before the end date.

ISDN SWITCH OFF TIMELINE:

2027
ISDN/PSTN switch off.
2024
Openreach announce 13 month delay to ISDN/PSTN switch off.
2023
Reduced analogue service availability extended nationwide.
2022
Analogue services begin to be withdrawn from UK exchanges.

WHAT ARE THE RISKS OF THE ISDN SWITCH OFF?

The biggest risk of the ISDN switch-off is the potential loss of phone communication. If businesses are not prepared before the switch-off date, their systems may stop working entirely.

Delaying action could also mean being stuck in a backlog of installations, leaving businesses without a working phone system for a period of time. This disruption can lead to missed customer calls, lost revenue, and damage to customer experience.

Loss of Phone Service

You need a scalable UC solution that your hybrid team can control from anywhere.

Business Disruption

Day-to-day operations can be impacted, particularly for teams that rely heavily on phone communication.

Missed Calls and Lost Revenue

Inbound enquiries and customer calls may be missed, directly affecting sales and customer experience.

Installation Delays

As the deadline approaches, demand for upgrades will increase, potentially leading to long installation lead times.

Higher Costs

Last-minute upgrades can be more expensive due to limited availability and urgency.

Impact on Other Services

Systems such as alarms, payment terminals, and entry systems may also stop working if they rely on analogue lines.

WILL ANYTHING ELSE BE AFFECTED BY THE ISDN SWITCH OFF?

Yes – the ISDN and PSTN switch-off affects more than just traditional phone systems. Any service that relies on analogue copper lines may be impacted, including:

Alarm and security systems
Payment terminals and card machines
Door entry and access control systems
Lift emergency phones
Fax machines
Older broadband and connectivity services

Many of these are “hidden” lines that sit outside your main phone system and can easily be overlooked.

If these services are not identified and upgraded in advance, they may stop working when the network is switched off, leading to disruption, security risks, or compliance issues.

Still on ISDN and unsure what to do next?

Don’t worry, we’ll guide you through it. Tell us a bit about your business, and our experts will recommend the right ISDN replacement to keep you connected before the switch-off.

Growing SME
The ISDN switch-off is your opportunity to upgrade. Move to a solution that grows with your business and keeps your hybrid team connected from anywhere.

Regulated Business
With ISDN being phased out, now is the time to switch to a secure, compliant solution. Protect sensitive data with built-in security and stay aligned with industry regulations.

Large Enterprise
As ISDN is retired, complex infrastructures need a smarter approach. Transition to a tailored UC solution with seamless integration and dedicated support SLAs.

The Next Step
Clarity, Control, and Confidence. Speak to an expert to discuss options on 0800 097 6543.

WHAT ARE PSTN AND ISDN?

Public Switched Telephone Network (PSTN) and Integrated Services Digital Network (ISDN) are the circuits that most of us currently use to communicate over the phone.

PSTN is an older technology operating using the same principles as the first ever public phone network. ISDN uses more recent technology to deliver both voice and data services over digital lines at the same time. It was once the go-to option, but it’s now showing its age and is increasingly not fit for purpose.

WHAT WILL REPLACE ISDN AND PSTN?

The demise of the ISDN line certainly isn’t negative for business though. VoIP systems, deliver many benefits and will transform your communications for the better both now and into the future whilst providing cost and productivity advantages. It’s time to think about switching now – fill in the form below to see how we can help.

PSTN and ISDN circuits will be replaced by VoIP (Voice over Internet Protocol) systems.

WHAT IS VOIP?

VoIP allows users to make and receive calls using the internet it converts voice comms into digital data that travels over an internet connection to its destination.

Calls can be made with any device that has a reliable internet connection, including a desktop computer, laptop, smartphone, or tablet. Extensive business features give users incredible flexibility to make and receive calls from anywhere without being dependent on a physical location like a traditional desk phone.

THE BENEFITS
OF VOIP

Call Quality

Call quality is arguably the most important factor to consider when choosing a phone system. Enjoy the crystal clear calls that are vital for your business.

Woman using headset in front of desktop computer

Multi-Functionality

Go beyond calls. With VoIP, you can message, video call, and run meetings all in one place, keeping your team connected wherever they work.

Security

Security against telecoms fraud is vital for every business. VoIP offers you more protection as it’s far more secure than traditional analogue telephone connections.

Portability

With the number of remote workers increasing at a rapid rate flexibility is essential. VoIP phones offer portability as they can be used anywhere so they are ideal for remote working.

Feature Packed

Built to save time, not create more work. Automate everyday tasks, streamline workflows, and reduce manual processes with smart, built-in tools.

Cost Effective

The system is cheaper to purchase and install with very little hardware costs. In addition, call costs are significantly cheaper when compared to traditional phone systems.

SIP TRUNKS

PSTN or ISDN circuits enable you to make external business calls. SIP Trunks are the modern way of transferring your external calls over the Internet.

Do you need to invest in SIP Trunks? No, Not with Enconvo Contact. Our business telephony solution comes with embedded SIP trunks, which means you have one bill, and all your external & internal calls will be managed by us. Enconvo integrated SIP Trunking offers better flexibility & cost efficiency. We also have built-in disaster recovery, which can be scaled up or down without additional physical line installation.

SIP trunks deliver better flexibility and cost efficiencies of up to 50% by simply connecting to the phone network via the internet. It may be more budget friendly, but it’s also incredibly reliable – ensuring your calls are never lost through line faults or power cuts. They also have built-in disaster recovery and can be scaled up or down without the need for additional physical line installation.

BENEFITS

Cost savings of up to 50%
No more physical infrastructure
No costly hardware investment
Simple management
Increased reliability
Keep your existing numbers
Better flexibility
Built-in disaster recovery
Totally scalable
Perfect for remote working

ARE YOU READY FOR THE ISDN SWITCH OFF?
PREPARE TO MAKE THE SWITCH

Download our Whitepaper, and read our blog to get the inside track.

ISDN will soon be a thing of the past : what will replace it?

This whitepaper gives an insight into the of the end of PTSN and ISDN, and how it will effect your business comms.

The end of ISDN is approaching, but what should you do?

This blog post gives tips on how to prepare to ensure vital communications continuity for your business.

Frequently Asked Questions

What is a business phone system and what equipment do you need?

A business telephone system is a phone system which improves your company’s ability to communicate at scale.

Traditional phone systems are built using analogue technology, this system is expensive and lacks features which modern businesses require to be successful.

Modern features such as:

Multi line holding
Auto attendant
Download Voicemails
Call recording
CRM software connections
Mobile integration

Modern day VoIP business phone systems use the Internet instead of a landline to transfer voice data at a much faster speed and at a lower cost.

The system is made up of a phone, computer, internet connection and a PBX box either hosted in the office or on the cloud. Cloud hosted PBX boxes help businesses become more dynamic with their work allowing for employees to work from home whilst retaining an office phone number and all the system features.

Will I lose my number with the ISDN switch off?

No, if you transfer your number to a new VoIP system you can almost always transfer your current number.

How do I install the new business phones?

Depending on the phone system you choose we have many options to help you install the phones.

In many cases the system will be a simple plug and play. If you occur problems our support team have exceptional facilities to live video guide you through installation.

We provide free on site support for large installations or issues unresolvable by call/video.

What Openreach products are affected?

The following Openreach products will no longer be available when analogue services are switch off in 2027:

WLR3 analogue
ISDN2
ISDN30
LLU SMPF
SLU SMPF
Narrowband Line Share
Classic Products

All of these products may also be known as WLR products.

Can I have broadband only and no line rental?

Yes, when you upgrade to a VoIP service we can provide you a single order broadband such as SoGEA. This will remove the need for a phone line but ensure your business remains connected.

What if I don’t upgrade before the ISDN switch off?

You will not be able to opt out of the ISDN switch-off. If your business has not upgraded to a VoIP service by 31 January 2027, your phone and/or broadband services will cease.

ISDN SWITCH OFF: WHAT IS IT?