PSTN/ISDN Switch-Off Is Coming: Port your number to eFax

By the end of 2025, UK Telecom Providers will have completed their PSTN/ISDN switch-off. If you currently operate over PSTN/ISDN, now is the time to switch and maintain your essential business service.

What Is ISDN?

ISDN is a common form of data transmission established in the 90s that sends information over copper wire systems. It is used by many millions of businesses across the UK. Often found in small businesses, ISDN sends digital messages through a landline using an adaptor or converter. Messages can then be transmitted to customers and clients through the internet. While it has been phased out in most private homes in favour of mobile technology and broadband, ISDN likely remains the primary method of sending fax documents and making phone calls for your business.


What Is the ISDN Switch-Off?

The ISDN switch-off is going to happen in 2025. British Telecoms (BT), the UK’s largest telecommunications provider, will cease to operate all of its legacy services. This means the infrastructure that used to enable old-fashioned landlines systems will no longer be operational. The result of the ISDN switch-off is that anyone currently sending fax documents and phone call data through ISDN will no longer be able to do so. The technology will become completely obsolete.

Move Aside ISDN

Get Ready for the Switchover with eFax Now!


Is The ISDN Switch-Off Bad News for Businesses?

The ISDN switch-off can mean only one thing for businesses still using the technology to transmit fax and phone calls: a change must be made.

Following the 2025 switch off, there will be no way to access or use ISDN to submit data using the platform, which means you will be forced to adapt to new communications systems. There is no getting around this fact.

This idea of forced change may be concerning for the millions of businesses still using ISDN. But while it is completely unavoidable, is this really bad news for your company?

The ISDN Switch-Off: A Blessing in Disguise

The change brought about by the ISDN switch-off doesn’t need to be alarming. In fact, it is going to be a good thing for your business. There is a reason BT has chosen to eliminate ISDN from its service structure. The technology is old and outdated. It isn’t cost-effective or efficient for businesses to keep operating in the modern day. There are much better solutions available. By being forced to update your technology, you could actually discover much more powerful communication platforms.

Platforms like eFax can transform the way your business sends fax documents.

How eFax Online Faxing Solves Your ISDN Switch-Off Problems

eFax is the ISDN alternative your business needs. Forget about sending fax using landline technology and step into the digital era. Our innovative and intuitive online faxing is so simple to use. It requires no additional training or IT knowledge — anyone can take advantage of eFax technology.

Easily integrate eFax into your business today and step away from outdated technology that is reliant on soon-to-be-obsolete ISDN.


Prepare your business for the ISDN switch-off now by moving to a platform that uses entirely digital technology.


Upgrade your fax solutions, remove the outdated fax machine from your business and start sending documents from your computer, smartphone and more.


Achieve more secure and stable fax solutions than other ISDN alternatives like VoIP.

Invest in Your Future Today!

Why wait years to secure a more stable future for your business? The ISDN switch-off means you are being forced to change, so don’t leave it until the last minute!

Sign up to eFax now, move away from outdated ISDN and start your digital fax journey. Enjoy the powerful benefits our cloud-faxing solutions have to offer, all while making sure you are prepared for the 2025 change!

Want to Know More about the ISDN Switch-Off?

Got more questions about the ISDN switch-off? eFax has covered everything you need to know in our comprehensive blog. From more in-depth information on the reasoning behind the switch-off to how it will really impact your business, our article explains all.

No obligation. No set-up fees. No risk.