What is the BT ISDN / PSTN Switch Off?

The switch off is the removal of the integrated service digital network and public switch telephone network. Basically, all voice traffic will need to work down the internet (VoIP).

When is the BT ISDN / PSTN Switch Off set to take place?

BT have announced that the switch off is due to take place at the end of 2025. The deadline is fast approaching so it’s worth looking into sooner rather than later. The longer you leave it, the more risk you have of losing your phone service.

Who will it affect?

The answer is quite simple, everyone that is still running their telephony over the BT copper network.

Why are BT switching off ISDN & PTSN?

The ISDN / PSTN network is now seen as being outdated and it doesn’t make financial sense to keep making improvements to it. VoIP (Voice over Internet Protocol) technology is far superior and more suited to current working requirements. The priority for Openreach moving forward, is to maintain a high availability fibre first network.

How do I know if I’m still using ISDN / PSTN?

All the services that you’re paying for should be listed on a bill from your supplier. If you’re unsure, they should be able to tell you. Alternatively, get in touch with us and we can often find out by looking on our portal.

Why Should My Business Switch From ISDN?

From 31st December 2025, traditional ISDN & PSTN phone lines will be switched off.

Cloud-hosted telephony alternatives offer much faster speeds than traditional phone lines.

Increased flexibility, allowing businesses not to be tied by physical locations.

What Are the Alternatives to ISDN & PTSN?

What will replace the traditional lines?

The two replacement products are SIP trunks or a cloud-based phone system. SIP trunks are phone lines that work down the internet and connect to your PBX. Cloud based phone systems are the way that most companies are now going with their telephony. The need to work from home was a major reason that this turned into the preferred method. Cloud systems come with plenty of features included and don’t often require a large upfront cost.

Both methods require a fast, reliable internet connection.

How Do I Switch from ISDN?

You leave this to a team of professional, experienced telecommunication providers. A number port is required, which is the process of moving your existing phone numbers to an internet-based product. Our team of experts at Barton Telecom Services have over 25 years experience and are happy to arrange all of this for you.

Contact Barton Telecom Services

Don’t hesitate to get in touch with one of the team to discuss your needs in more detail, simply leave us a message on the contact form below or call us on 01604 812813.

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Customer Reviews

5 star rating on googleThe Barton Telecom Services team have recently installed a new phone system for us and brought us right into the 21st Century. The process was seamless; from us explaining what we needed, them explaining the best and most cost effective way to achieve it, right through to installation. The team are always willing to answer any question, no matter how silly, and are quick to respond if we have a query. They really are great, and we would have no hesitation in recommending them!

Lisa Braithwaite

The Lowdown


Got A Question Around The ISDN Switch Off?

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