A guide to switching from ISDN to VoIP

With ISDN phone networks being phased out, you’re probably thinking of switching your system to a more modern phone solution. This is where Voice over Internet Protocol (VoIP) comes in. VoIP is currently one of the most popular digital phone systems available. Not only is it cost-effective and easy to use, but it can also help improve your business communications and allow employees to work more flexibly too.

There are many reasons why you should use a VoIP phone system, from its advanced features to its simple integration and scalability. And here, we’ll explain just how easy it is to switch from ISDN to VoIP in 5 simple steps.

VoIP: an ISDN replacement

In 2025, BT will be switching off both PSTN and ISDN networks. This will impact all businesses that still use an analogue phone system. The reason why they’re turning these networks off is simply that they are outdated. These systems were created in the 1800s, and the business world is moving on to more modern ways of communicating. They are also much more costly to run and maintain. VoIP technology, on the other hand, is cheaper, faster, more reliable and future-proof.

What’s the difference between ISDN and VoIP?

ISDN was created in 1986 by BT as a more modern phone solution to the outdated copper lines of PSTN with faster speeds, higher quality calls and better connections. However, in recent years BT has focused its efforts on VoIP services, leaving ISDN behind. As ISDN hasn’t been changed or updated, it can no longer compete with the ultra-fast speeds, quality and ease of VoIP. 

The main difference between ISDN and VoIP is that ISDN lines are fixed and require hardware, whereas VoIP only needs a stable internet connection to work and can be downloaded onto your computer or smartphone.

How to switch to VoIP

Here’s how your business can switch from an ISDN network to a faster, easier, and current VoIP network in just 5 easy-to-follow steps.

1. Plan and Research the Switch

First and foremost, you’ll need to plan and research the switch. While switching to a VoIP network isn’t a big project, it still needs a little bit of work to ensure everything changes over smoothly. We recommend looking at your current system and answering the following questions:

  • How many phones do you have, and how many do you actually need?
  • Do you need extensions for different departments?
  • How often do you make international calls?
  • Do your employees work remotely?
  • Do you use voicemail, call routing or call queues to handle missed calls?
  • Will you benefit from extra services, such as security, management or analytics? 

These questions will help you understand what functions from a VoIP system will be useful for your business as well as assess what you no longer need from your current system. At Officeology, we can discuss your business phone system options and guide you in the right direction when it comes to choosing the best solution.

2. Test your Internet Connection 

Since VoIP uses the internet to work, you’ll need to make sure you have a strong business broadband connection. Luckily, the majority of internet providers are more than fast enough to handle a VoIP system. You will have to consider how many employees you expect to be using the system at the same time to decide on your needs. For example, a small company of 10 employees should have no problems with a lagging connection, compared to a larger company where hundreds of people are making and receiving calls.

We’d recommend testing your internet connection and running a VoIP speed test to find out if you need to increase your bandwidth, then speaking to your current internet provider for an upgrade if needed.

3. Choose your VoIP Provider

Choosing your VoIP provider can become overwhelming with so many choices and options available. To start your search, refer back to your initial questions and decide which features are most important to the running of your business. Some popular VoIP features include:

  • Video calling
  • Text messaging
  • Team chats
  • Voicemail 
  • Speech-to-text translation
  • Call routing
  • Auto attendant 
  • Call queues
  • Call analytics 

You’ll also want to consider the most cost-effective provider and a provider that offers exceptional security and support so you can contact them easily if an issue ever occurs.

4. Consider your Hardware

When switching from ISDN to VoIP, you may wonder what to do with your old phones and hardware. If you decide to keep your desk phones and headsets, then you’ll need to look into a cloud-based system that has VoIP capabilities which can be connected to your current phones and re-route calls through the internet.

However, VoIP technology doesn’t need any hardware to run, which means you can ditch the desk phones, clear up space in the office and offer more flexibility to your employees. Since a VoIP system uses the internet, you can use business phone apps on your business computer or smartphone to make calls wherever you are. This is ideal for employees who work from home or travel and is a much more cost-effective solution.

5. Set Up and Connect the New System

Lastly, after you’ve chosen a provider and decided what to do with your current hardware, it’s time to set up and connect the new VoIP system. Generally, setting up a VoIP system is very quick and easy, depending on the chosen provider’s instructions. In most cases, all you need to do is connect your compatible devices to the internet and wait for the connection to appear in your VoIP software.

From there, you can configure your system and enable the integration of your business tools and software to streamline your workflows and business communications.

For a more detailed look, read our guide on how to set up a VoIP phone system. If you’re interested in VoIP business phone systems, just get in touch with our experts today.

Get in touch

Need some help to get your office running like a well-oiled machine? We can make that happen.

Give us a call or send us an email and one of our team will be on hand to talk you through how we can help.

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