Big 2025 Switch off


Worried About The PSTN & ISDN Switch Off?

Are you aware that the way we make telephone calls is changing?  46% of 400,000 UK SME businesses recently surveyed, had no idea.

BT has announced that it will be retiring the PSTN and ISDN networks by December 2025. This is a phased switch off which started in 2020 so your service could be affected a lot sooner than 2025. 

The purpose? Replacing old cabling and equipment with new technology much better suited to the digital age. The rollout of this new infrastructure is already very much underway.

What does this mean for you? Will your telephones and internet still work when these networks are switched off, or should you be looking to do something about it now?

Why wait until the last minute? Dealing with this sooner than later actually brings a number of benefits, so it could be worth speaking to someone to see how this could help you.

Here is some more information about the upcoming switch off and how you can prepare.


What are PSTN and ISDN lines?

Put simply, they are both types of telephone lines. PSTN lines tend to be traditional phone lines able to deal with one call at a time, and may also carry broadband internet services over the top. 

ISDN2 and ISDN30 were the successors to PSTN, with more capacity providing either 2 or up to 30 channels of voice (or data), normally into an on site “switch” also referred to as PBX or phone system. The purpose of all these lines is so that more than one user can make or take a call at any one time, without additional callers receiving an engaged tone. 

The more lines you have the more people can talk concurrently.


What Is The PSTN & ISDN Switch Off And Why Is It Happening?

PSTN means Public Switched Telephone Network, and is the type of line most houses and small businesses have used for many years. They remain largely unchanged from when first used in the early days of telephone usage. 

Consisting of a “copper pair” they were never really intended to be used for anything other than voice calls. If you remember dial up internet, you may remember how slow this was, and how you could not also use the phone at the same time. 

The advent of ADSL (Asynchronous Digital Subscriber Line) broadband a few years later meant internet services could run over the top of a PSTN line and the phone line could still be used for voice, but ADSL was still relatively slow in comparison to today’s expectations.

ISDN means Integrated Services Digital Network. When introduced in the 1980’s they vastly improved upon the PSTN lines that already existed. They allowed users to have not only voice functionality but also use relatively low bandwidth data and video. 

Tech Update

Technology has changed dramatically since the 1980s. ISDN is no longer fit for purpose when it comes to providing us with the capabilities we need in an ever-increasingly digital world, in business or at home. 

If you have ever seen old 1990s episodes of Tomorrows World, you will see that the way we consume digital content nowadays, would not be possible if we were to stay on the old networks of yesteryear. 

With rich media content almost everywhere we turn, the connectivity needed to deliver the additional bandwidth needs to have much greater capacity.  Moving to an all digital infrastructure will make this possible.. 

When the PSTN and ISDN networks get retired, telephone calls will all need to be made over digital IP connections instead of analogue signals.


Should Your Business To Be Worried?

The simple answer is, YES, but don’t panic just yet.

It is important that you think about things now and do not leave it too late. You have time to find alternative options that suit your needs.

Leaving things until the last minute could cause unnecessary stress and disruption to your business and your clients. Many businesses are already migrating across to these new services, however almost half so far have not.

Millions of UK lines need to be moved to alternative technologies, and they won’t be done automatically. We are aware consumers are starting to be being contacted by their telecoms companies often being offered a simple moves to broadband based calling simply by moving their existing telephone cable from the main socket to their broadband router, but for businesses with more complex needs, it is not quote as simple.

As more time goes on, the more you risk the services not working properly due to the gradual switch off. You might find that there will be less assistance available if you have problems with an old phone system.

It could be worth checking when your current contract ends. There may be options to migrate to cloud or end an agreement early. 

We have helped some customers pay off old agreements and migrate to new services, we might be able to do the same for you?


What Do You Need To Do In Preparation For PSTN & ISDN Switch off?

Below are some ways that you can make sure you are prepared for the switch off: 

Research voice technology and how you will use this moving forward. This means looking at how you can use IP enabled phones as part of your business. Try and embrace the use of the new technology and recognise how this will benefit your business. It makes things like allowing your staff to work away from the office much easier and the overall quality of your calls will be much better.

 Think about the plans you have for your business in the near future. Do you plan on moving or expanding into new premises? Do your staff need to work out of the office? These questions can help you plan for choosing a service that works best for you and your needs. 

Don’t rush into buying a replacement solution when you could get advice to help you choose something that is exactly what you need.


Three Alternatives To Consider.


SIP trunks are virtual phone lines provided over an internet connection rather than physical lines such as ISDN. You could use SIP trunks to get the benefits of IP telephony, but still keeping an existing traditional on premise phone system in place.

Note: Your system has to be SIP ready and or you might need to invest in a SIP gateway. A relatively easy quick fix although you may find getting support for physical systems becomes less and less available (or more expensive if parts become more scarce).


With many businesses using Microsoft Teams/Office 365/Zoom day in day out, the need for a physical phone on every desk is no longer what it once was. In a similar manner to SIP trunks, “Direct Routing” can allow phone numbers to be routed directly to applications already installed on business machines and mobiles. 


Moving to a Cloud based or “Hosted” VoIP solution. Rather than a cumbersome physical on site “switch” or PBX, this is a virtualised phone system hosted in the cloud that can be managed from anywhere. Cloud based systems have been around for a number of years now and offer much more flexibility than traditional phone systems, plus greater ability to manage users based over multiple locations. 

Sites and users can be added, hunt groups created so that calls reach the right people no matter where they are located. Cloud hosted phone systems can be provided with a physical IP enabled desk phone, smart device app or computer app (or combinations of or all of the above) to make and take calls. 

We have spoken to many businesses who now operate their business telephony via mobile apps since the Covid outbreak and like the freedom and flexibility it gives them.

Options are often available where the phone hardware is provided free or subsidised so you do not have an initial outlay or expensive maintenance to pay for unlike an on site PBX. A cloud based solution can often also integrate with other UC applications you may already have.


Ready To Switch?

 While it might feel like a huge upheaval, telecoms companies have been preparing for this for many years and are doing so on a huge scale. The recent pandemic has made businesses around the world realise that moving to a digital environment such as hosted, offers not only much greater flexibility, but can also dramatically lower costs and provide more insights into how communications platforms are used in the business.

The process itself doesn’t need to be difficult and you certainly don’t need to get flustered about it. There is plenty of help and advice available.

The best thing you can do to protect yourself is to start researching and considering your options now. This will put you in the strongest position to  minimise disruption  when the changeover happens. 


Sooner Or Later?

If you leave switching until the last minute, there is also the chance of being in a queue for help. This could mean being without a phone line in the meantime, which is of course, is bad for business. Switching early allows you to be sorted before the rush! 

If you would like to talk to us about your options, you can get in touch in a number of ways.

Use our 2 min typeform, our contact pageor give us a call on 03333444190 and we will help you find the best solution for you.

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