ISDN & PSTN Switch Off

It’s time to get clued up on the ‘BT ISDN Switch Off’ – an important transition that will alter the way people make phone calls in the UK. Companies must be proactive and prepare now for 2025, when the official switch off goes ahead. That’s why we’ve put together this helpful 5-minute guide to getting informed about what you need to do for business continuity. Take a look at all you need to know and get ready for the big change!

What is PSTN?​

PSTN (Public Switched Telephone Network) is a traditional telephone network that uses copper wire networks and fibre-optic cables to transmit voice communication from one location to another.

This type of network has been in use since the early 20th century, and it allows people to make both long distance and local calls. PSTN technology is still widely used today, though its popularity has decreased as more modern forms of telecommunications have become available

What is an ISDN line?​

ISDN stands for Integrated Services Digital Network.

It’s a group of communication standards that use digital transmission to make phone calls, video calls, transmit data and other network services over the circuits of the traditional PSTN (Public Switched Telephone Network).

In 1986, BT introduced ISDN in the UK.

It replaced old analogue landlines to digital lines, adding features that weren’t available with a classic telephone system

What is the 2025 ISDN switch off?

The 2025 ISDN switch off is a significant milestone in the UK’s digital transformation, as it will mark the end of PSTN (Public Switched Telephone Network) and ISDN (Integrated Services Digital Network).

Neither of these technologies are capable of delivering the volume or quality of voice data needed in this increasingly digital world.

Voice calls in the future will be made over the internet.

This means that by 2025, all businesses must migrate their phone systems to modern digital solutions such as VoIP (Voice over Internet Protocol) or SIP Trunking. 

Why is ISDN being switched off?

ISDN has come a long way since its introduction in 1986, yet the network core remains largely unchanged and is now beginning to feel outdated. Broadband connections offer much faster speeds, making ISDN’s capabilities seem measly by comparison.

Traditional ISDN lines also don’t provide much flexibility; tethering businesses to physical locations which no longer meets their needs for scalability and remote working solutions.

In 2015 BT declared it would shift its focus from updating the aging ISDN network, redirecting resources towards more advanced technologies such as VoIP — ultimately allowing them to keep up with the growing demand from businesses while building services for the future.

What will replace ISDN?

There are two options that will replace ISDN, VoIP and SIP.

What is VoIP?

Voice over Internet Protocol (VoIP), also known as IP telephony, is an advanced set of technologies that enable the delivery of voice communication and multimedia sessions across IP networks.

Using VoIP, analogue voice calls are digitised and sent in packets of data through either public or private Internet Protocols (IP). This allows them to travel with similar ease and security as other forms of data—such as emails.

What is SIP?

Session Initiation Protocol (SIP) provides a reliable, secure way to connect with other users via multimedia communications. It is the protocol of choice for Voice over Internet Protocol (VoIP) calls, allowing you to make and receive calls directly through your internet connection.

SIP also enables you to host video conferences or connect multiple devices in an IP network, making it easy to stay connected even across long distances. With its user-friendly interface and cutting-edge security features, SIP ensures smooth communication every time.

What can I switch to?

If you’re transitioning away from ISDN, consider VoIP as an option if you’re looking to purchase a new phone system. Alternatively, SIP is an ideal choice if you want to keep your current setup in place. Rest assured that we are here to guide and support you throughout the entire transition process.

How to switch from ISDN to hosted VoIP

SIP and SIP Trunks are a great on-premise solution for a phone system as they provide virtual phone lines rather than physical ones. You can use systems like mayfone and Direct Routing for Microsoft Teams with these trunks, which come with the added benefits of flexibility, speed, quality and cost savings – making them an increasingly popular option when compared to ISDN.

To ensure you don’t lose your existing telephone numbers, you should consider porting them to us. This process requires coordination between our team and your previous provider, along with any location-specific numbers you’d like to keep. As part of our service we offer number porting which can take up to several weeks depending on the specifics of your agreement and the amount of numbers you wish to move over.

What are the benefits of switching?

Switching comes with a wealth of advantages that you’ll be glad to know about. Cost-wise, you can anticipate drastically reducing your call charges and line rental.

No matter what platform you’re using right now, we’re sure that switching will make a big difference in terms of savings!

You’ll also have access to an array of features not available on traditional landline systems – think voicemail and conferencing capabilities, presence status, switchboards, CRM integration and more. Unifying phone calls with emails, messaging, scheduling and staff status has never been easier!

Once you become a customer of ours, the speed and efficiency with which you deal with customers goes up considerably. This is all made possible by VoIP technology which gives unparalleled control over your calls – so now it’s easy for you to monitor performance levels and pinpoint areas for improvement.

No need to worry about data loss either; our disaster recovery system is designed for minimum downtime and data loss situations – we even store regular ‘snapshots’ of your data each day just in case something untoward should happen! With this feature at play, restoring your last usable snapshot typically takes no longer than an hour – meaning you’re back up and running in no time at all!

When are you going to switch?

If you’ve already made the switch, well done you! 

If you haven’t, now would be an ideal time to consider the alternatives to ensure your business is prepared for the switch off.

Is your current phone system, IP compatible?

One key factor for making the switch to IP-based technology is considering the compatibility of your current phone system. Take a look and determine if it’s up-to-date enough to support IP. If needed, investing in a newer system may be necessary! An even better option is replacing your existing ISDN service with SIP Trunking – this will ensure you’re able to take full advantage of the benefits that come with IP telecoms technology.

To ensure success on this journey, it’s important to assess your internet connection as well. Is it stable enough? If not, switching to a fibre optic connection or Ethernet-based leased line could provide an optimal experience and help make sure everything runs smoothly!

How long does it take to switch over?

We understand that transitioning your business to a new phone system can be time consuming and complex. But, thanks to our extensive expertise, we want to make this process as seamless and stress-free as possible. 

From porting the communications infrastructure to ensuring a smooth transition with no disruption of your day-to-day operations – you can trust us every step of the way.