01604 926100


Ultrafast Connectivity · Secure Analytics · Smart Energy
Rugged Technologies · Outdoor Wireless · Fibreglass Technology · Secure Data Storage · Consultancy

December 2025: BT To Switch Off PSTN Networks

Or so they say ...


Posted by Pritesh Ganatra on 16/05/2023 @ 8:00AM

Since 2008, where ever possible, transmitting voice services over the Internet rather than an analogue phone line has been in testing within the industry with clients and customers who were asked to be early adopters of this technology ...

Everyone is switching to fibre in 2025. Or so BT say!

Everyone is switching to fibre in 2025. Or so BT say!

copyright: wklzzz / 123rf

There have been rumblings within the industry since then that Openreach, the division of BT that owns and operates the majority of the UK telephone network, will be switching off all PSTN and ISDN services in December 2025.

"Formal announcements of this major change were finally
revealed to the industry in 2018!"

They talked of the new products and processes that Openreach had been trialling in their network to be able to withdraw PSTN/ISDN services and thus, a bit like 'Making Tax Digital', all equipment connected to a pure 'copper' network and is reliant on a 'dial tone' will, in effect, stop working.

Voice over Internet Protocol (VoIP) and Session Initiation Protocol (SIP) are the replacement technologies behind the ability to make a simple phone call from a desk or DECT (cordless) handset. Both are based on Internet Protocol (IP). But before we get to that, let's take a closer look at how the 'big copper switch off' will affect homes and business in the UK.

Many elderly people still don't have Broadband as we know it. They still have a standard, analogue line, delivered to their home by a standard copper pair and the wires go straight into a wall socket with a phone plugged in. A phone number is associated with the service, generated from the BT exchange. A caller dials the number at one end and the handset rings at the other.

This scenario is the same for Nurse Call systems, PSTN lines in elevators (Lift Lines) and many other single-product devices such as older alarm systems that used a service known as Redcare.

The vast majority of PDQ (credit card) machines are also connected to a standard phone line, but they can be upgraded to use Wi-Fi if you talk nicely to your provider, but do this as part of an overall project network as now, cybersecurity comes in to the equation as well.

There are thousands of older, hardware-based Telephone Systems (PBXs/PABXs) in use, all connected to either ISDN2e or ISDN30e services that are the digital side of the PSTN infrastructure! There are also tens of thousands of broadband services that are underpinned on a PSTN line, with a working phone number attached. You may see invoices with a charge for the phone line and another charge for the broadband against the same phone number. This type of service is part of the switch-off.

"So, what are the alternatives I hear you ask?"

Since 2018/9 most new fibre-based broadband services that would have been installed (or should have been installed) have no dial tone, although the NTE is exactly the same as the current set-up. I.e., the box on the wall still has the standard phone outlet, but is not in use. This applies to all areas where Fibre-to-the-Cabinet (FTTC) services have been deployed.

Pure Broadband services are data only and do not allow standard phone calls unless a VoIP service (or SIP services terminating on an IP PBX) is subscribed to by a Hosted Phone service provider.

This is not the same as full fibre (Fibre-to-the-Premises/FTTP), which is being laid from the BT exchanges directly to your doorstep. This service accommodates up to 1Gbps data transfer rates and now multiple private companies are also laying their own fibre services to compete with Openreach. Companies like Virgin Media and City Fibre are completely independent, own and operate their own networks, fibre exchanges and infrastructure setup.

When it comes to the mobile networks, we have used apps on our smartphones for a few years now. Apps like Facebook Messenger, WhatsApp and even Twitter all use the mobile data connection (not the voice side) of the mobile networks to initiate a voice call, hence classed as VoIP technology, but you still need the SIM card for voice calls unless you use the smartphone purely on WiFi from a broadband connection.

"Is this the end of the copper pair?"

The humble two-wire copper-pair technology for making and receiving phone calls that has served the UK so well for generations is finally set to be retired and VoIP will be the norm. The 50-volt exchange equipment that generates the PSTN dial-tone and the 90-volt exchange equipment to generate the ISDN2e/30e dial tone are specifically the two technologies that 'the big copper switch off' refers to.

The physical copper pair, for now, will carry SoGEA (FTTC minus dial-tone) broadband technology until UK PLC has fibre to the premises of every home and small business and is suitable for VoIP for up to approximately 20 people. After this point, private' fibre/leased line technology is a much more stable connection for VoIP.

"Definitely seek some good advice!"

Now, is the time to review what types of phone lines and broadband services you have in your business as there are so many variations and factors to take into consideration. There is not long to go now until December 2025 and there is no guarantee that Openreach will delay any PSTN switch-off for the reasons mentioned above.

I recommend that you seek advice sooner rather than later if you are using any standard phone lines and especially if you have a telephone system such as Avaya, Mitel, Alcatel-Lucent, Nortel, Panasonic, Samsung, Shortel, Toshiba to name, but a few.

Until next time ...



Would you like to know more?

If anything I've written in this blog post resonates with you and you'd like to discover more about the BT/Openreach big copper switch off, it may be a great idea to give me a call on 01604 926100 and let's see how I can help you.

Share the blog love ...

Google AMP  /  Précis  

Share this to FacebookShare this to TwitterShare this to LinkedInShare this to PinterestShare this via Buffer

#TechnologyProblemSolver #Communications #IT #Consultancy #Northampton #UK

About Pritesh Ganatra ...


The word 'Technology' has too many connotations in today's world!

Where do we start? Simple terms like 'IT' and 'Telecoms'? or terms that appear NOT to have an actual meaning at all!, e.g. 'Internet of Things (IoT).

Technology also encompasses specialist products and services like 'Rugged' and 'Tough' android devices, Lone Worker Software, panic alarm devices, smart energy devices, low energy lighting, credit card terminal (PCI DSS) security, indoor/ outdoor Wi-Fi systems, Ultrafast Gigabit internet connectivity, access control systems, industrial IoT circuit controllers.

BTS UK can consult from simple solutions to the most complex, provide some of the products through a wholesale channel, bring together a multi-disciplined 'Task Force' to deliver and implement complete Technology 'projects'.

I am your technology problem solver and I look forward to helping you.


01604 926100