2025 Switch Off

The 2025 Switch Off

What is the BT Openreach 2025 Switch Off?

The 2025 Switch Off is the planned discontinuation of PSTN (Public Switched Telephone Network) and ISDN (Integrated Services Digital Network) services by BT Openreach.  This process begun in 2020 and will end with the complete shutdown of PSTN circuits by December 2025.  It is important to act now to ensure a smooth transition and avoid interruption of your business-critical communications. 

Take a look at the BT Roadmap below.

The Impact to Business

Businesses that still use PSTN or ISDN networks will be impacted by this switch off and should start planning to move to alternative communication options, such as cloud telephony or VoIP, to maintain uninterrupted service. It is vital to start planning early and to collaborate with a trustworthy telecoms expert to make the transition as seamless as possible.

As a business you should plan to migrate to alternative solutions. To find out more read some of the FAQ’s below. Alternatively, you can contact a member of our sales team; who can assist you in getting ready and prepape for this transition. 

The Big Switch Off Roadmap
Scroll along to see the key moments in Openreach's road to the 'Big Switch Off'
November 2017
BT Openreach announce Intention to turn off all WLR products including ISDN & PTSN lines.
January 2018
Openreach improve their network with a 'Fibre First' strategy, aiming to make new Fibre technologies accessible to all.
December 2020
A 5 year reminder that all WLR services are being withdrawn in December 2025.
September 2023
The 'National Stop Sell' - signifying that all WLR services can no longer be sold across the whole of England.
December 2025
The current target date for Openreach to turn off all WLR services including ISDN and PTSN.
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ISDN is a circuit-switched telephone network that transmits voice and data through digital lines. It was developed to provide better voice quality compared to PSTN, but it is still considered a traditional telephony system as it relies on cables. Many businesses have been using ISDN for decades, as it was the standard for telephone and data communications.

The BT Openreach 2025 Switch Off is happening because the ISDN network is no longer able to support the speed, scalability, and method of communication that modern businesses need. Additionally, the company will cease its PSTN services to encourage companies to migrate to telecommunications solutions that enable them to grow at the pace they want. BT Openreach is actively promoting all-digital communication systems, such as cloud telephony, hosted PBX, and other internet-based communication systems as replacements for legacy telephone systems.

To prepare for the 2025 Switch Off, businesses should start planning for the transition as soon as possible. This may involve researching alternative solutions, such as VoIP, and identifying potential providers. Businesses should also consider the costs involved in upgrading their equipment and infrastructure, and ensure that they have the necessary budget in place.


It is also important for businesses to communicate with their employees about the 2025 Switch Off and to provide training and support to help them adapt to the new technology. This will help to minimize disruptions to operations and ensure that employees are able to continue working effectively.

It will if you're still on a legacy line. 


The 2025 switch off will greatly impact businesses that still use landline telephones and fax machines. You will need to consider how this change will affect how your staff communicates with clients, customers, partners, and vendors and how you will adapt to the change. About 2.4 million businesses in the UK still operate on PSTN or ISDN, with most being small and medium-sized enterprises. Some larger organisations have yet to make the switch. Roughly 33% of large corporations still rely on analog for a portion of their communication processes.

The switch off is a significant change in the telecommunications industry. The network shutdown began in 2020 and will be fully discontinued by December 2025. This means that all businesses and homes that currently use ISDN will need to migrate to a new system by this deadline. 


if you aren’t sure of if or when the Switch Off is in your area, you can ask a member of our team to take a look for you and see if there is any information.

As the UK moves away from the traditional analogue lines, ensuring that yours are updated is important.

But what to? Here are some alternatives:


SoGEA, otherwise known as Single order Generic Ethernet Access, eliminates the need for a traditional phone line. Instead, it runs as a data only service, providing your business with broadband through a singular order.

What are the benefits?

  • Removes the need for a PSTN line
  • Cheaper than FTTC and FTTP broadbands
  • Easier installation with little to zero engineering costs 
  • Having only one line allows for quicker, easier and more cost effective solutions


Fibre To The Premises. Within this solution, the fibre optic cables connect your business premises straight to the exchange. With the transfer of information being via pulses of light, data through these cables travels as fast as the speed of light, being unaffected by distance and demand. 

What are the benefits?

  • The dedicated full fibre connection prevents your business from peak time slow downs
  • Capable of super-fast speeds in comparison to your legacy broadband, reaching download speeds of 900Mb/s
  • Estimated investment of up to £28 billion by 2050

Alternative solutions to ISDN include cloud telephony, VoIP, and SIP Trunking. Cloud telephony is a cost-effective solution that allows for a remote workforce and scalability. VoIP uses the internet to make phone calls and is a popular alternative to ISDN. SIP Trunking is a ready-made successor to ISDN that offers advanced functionality and improved productivity. It allows for centralisation of operations, easy IT management and dashboards, the ability to transfer and redirect numbers, hot desking, and greater mobility for staff. Additionally, adding channels with SIP is a simple and easy process that doesn’t require any physical installations. These solutions provide businesses with a more flexible and reliable way to communicate and support a modern workforce.

The 2025 switch off is a significant change in the telecoms industry that will affect businesses still using landline telephones and fax machines. With the deadline for the switch off quickly approaching, it is important to start planning your migration strategy now to minimise downtime and ensure the smooth running of your business. There are several alternative solutions available, such as VoIP, cloud telephony, and Hosted PBX, each with their own unique benefits.