ISDN eGuide: The Big Switch-Off

3rd August 2021


Introduction to the Guide

In 2020 BT stopped the purchasing of ISDN lines and have announced plans to officially switch off ISDN network by 2025. Many businesses are now tasked with finding an alternative communication solution, this can be a challenging experience for any business. Here at ICA we have created an easy step by step guide to help you make the right decision for your businesses communication needs. We will cover what ISDN is, the effects it has on your business and how you can prepare for the switch off plus much more information so grab a coffee and have a read through our easy to use guide.


What is ISDN?

ISDN or Integrated Services Digital Network is a circuit-switched telephone network system that transmits both data and voice over a digital line. You can also think of it as a set of communication standards to transmit data, voice, and signalling.


Why is ISDN being Switched-Off?

Since its inception in 1986, ISDN has become an outdated and costly network to maintain for Openreach, a new technology called VOIP (Voice Over Internet Protocol) has become the solution of choice for businesses across the UK. VOIP offers a much faster, cost effective solution as an alternative to ISDN with many more expandable features to suit your business needs, BT decided to begin investing heavily in VOIP.
By 2025 the VOIP network will be able to support all communicational needs without using the ISDN network officially making the network redundant, there are many benefits of switching over to a VOIP based communication system but the main benefit is flexibility for your business with its ever increasing features and no maintenance costs you will be wondering why you didn’t switch sooner.


Why Switch Now?

The ISDN network is being switched off in 2025 so why look at a new solution now? 2025 feels like such a long way away that a lot of businesses are choosing to wait to switch over to a VoIP/Cloud based way of communicating.

This delay will cause a backlog of businesses across the UK that need a new form of communicating. A massive 6.4 million business across the UK need to invest in a new solution for their business’s communicational needs, that is 156K businesses a month who are required to move over to a new solution before the network is switched off. This will create a demand for a more feature rich digital form of communication which will in turn future proof your business and ensure communication is at the heart of your business.

Not taking the decision to switch now to a new solution could cost you more if you wait until 2025, future proofing your business has never been so easy and cost-effective.


What Solutions are there?

There are two primary solutions that most businesses switch to, these are VoIP or SIP, this depends on the business requirement. Below we will cover both solutions.

Hosted VoIP

VoIP uses the internet to make and manage calls and other multimedia services. If you do not want to commit to an on-premises phone system, VoIP is the best option for you. VoIP does not have any physical lines or hardware (other than handsets) which can reduce maintenance costs.

Believe it or not, switching from ISDN to VoIP is extremely simple. You just contact a telecoms provider, such as ICA, and they will take care of the set-up for you. ICA will go through your business needs/wants and conclude the best solution for your business. We will then deliver, install and maintain any VoIP solutions and provide full training on the software.


Session Initiation Protocol (SIP) is one of the possible protocols used in VoIP communications and is a great on-premises solution for a phone system as they use virtual phone lines rather than physical. There are two components to this, SIP and SIP Trunks.

SIP are the rules that allow you to make and end connections in data and voice transfers over the internet. SIP Trunks is the service that allows you to use that on a public network. These are also popular alternatives to ISDN as they are flexible, fast and low cost.

Switching from ISDN to SIP is also extremely simple, you simply need to contact a provider, such as ICA, and we will plan to port your numbers so that you can keep location specific phone numbers, we will also maintain and train any staff to use these systems.


Benefits of this Switch?

The switch from ISDN to IP technology is extremely simple and seamless with no impact on your business. Whether you choose VoIP or SIP, you will see benefits to your business in a multitude of ways.

Cost effective

The switch from ISDN to IP technology is extremely simple and seamless with no impact on your business. Whether you choose VoIP or SIP, you will see benefits to your business in a multitude of ways. You are also not restricted to minute plans, meaning you no longer need to pay for calls.

Disaster Recovery

VoIP allows for great disaster recovery as all data and functionality is provided in the cloud, meaning there is no disruption due to loss of service or information. If there were any issues with phone systems due to power cut or other natural disasters, your VoIP would resort to a comprehensive disaster recovery service, including cloud back-up, rerouting to mobiles or remote access to the system.

Call Features

VoIP has an abundance of call and media features, these include call queues, call recording, voicemail to email to name a few, VoIP also allows people to make voice calls on their mobiles through a mobile app feature or using a soft client via a laptop or desktop, offering mobility and flexibility.

Unlimited Flexibility

With a broadband connection, you can use VoIP anywhere in the world with little effort. This is great for businesses who have multiple remote workers or for those who are on the go.


Ready to make the Switch?

Here at ICA, we have a unique approach to communication and connectivity, providing bespoke solutions to businesses of all sizes with various communication and connectivity needs.
We will assess your businesses needs and understand how your business operates before providing a full solution to fit your businesses requirements, we will then install and maintain the solution providing full training and support throughout the journey with ICA.

If you’re looking to make the move from ISDN to VoIP or SIP, contact one of our specialists today or give us a call on 0161 443 5000 for a free no obligation chat to see how we can help your move easy and stress free.


.pdf The Big Switch-Off eGuide See this easy, comprehensive eGuide for the ISDN Switch-off