How to get ready for BT Switch Over Day

How to get ready for BT Switch Over Day

The Old System

The landline phone network that has existed since the 1800s is coming to the end of its lifespan. It’s current infrastructure, amazingly, still resembles the original systems of the Victorian era, using copper wires to carry the phone signal between users.   This is called a PSTN, or Public Switch Telephone Network. Even though a lot of it has now been digitised, (creating what is known as ISDN or Integrated Services Digital Network) large parts of the network still use the old PSTN circuits.

As our communication needs change, the old system is becoming creaky and unable to keep up. BT is planning to retire both the ISDN and PTSN circuits and replace them with fibre. Fibre networks offer faster speeds than the old copper ones and are also more reliable and easier to maintain.


The New System

BT plans to switch off the old network by 2025 and work is already underway to switch areas over to a new, faster and more resilient technology called VoIP (Voice Over Internet Protocol). You may already use this technology without realising it if you use Facetime, Zoom or Skype to chat to family, friends or colleagues. It means that calls can be made using an internet connection, and that is what BT plans to do with their network on Switch Over Day.  This system may also benefit end users as using the internet to make calls, particularly long distance ones, is considerably cheaper than using the copper network and it’s various switches required to complete the circuit along the way.

Switch Over Day will affect homes and businesses across the UK, and as BT/Openreach own most of the infrastructure across the UK, this will affect other telecom providers such as Talk Talk, Plusnet etc. However, in March 2021 telecare provider “Taking Care” surveyed more than 2,000 UK adults and found that 91% were unaware that all phone lines would become digital by the end of 2025.

What does this mean for you?

Well, no need to panic.

East Cambridgeshire’s Exchange is moving across to the new system from now. There is no single “Switch Over Day” for everyone, so your Switch Over Day may be different to one of your neighbours up the road. BT will send you a letter to let you know that your telephone network is due to be upgraded to the new system that they have called “Digital Voice” and will let you know what date will be your Switch Over Day.

For most households it’s a case of simply plugging your phone cable into your Smart Hub 2 on Switch Over Day, no BT engineer is required.

What to do on Switch Over Day


Step 1: Remove your phone cable from the socket in the wall


Step 2: Peel off the black Digital Voice sticker on the back of your Smart Hub 2


Step 3: This will reveal a green port


Step 4: Simply plug in the phone cable


Step 5: If you hear a dial tone, you're all set up and ready to make and receive calls

You're all set!

If you are in East Cambridgeshire and elderly or classed as vulnerable and struggling with doing this, please contact us and we’ll help you with it, free of charge.

Important points about Digital Voice

  • Your phone number won’t change and there will be at no change to your contract or call plan.
  • You will notice a different dial tone.
  • You will need to enter the area code even when making local phone calls.
  • You may need some new equipment – BT will send you a Smart Hub 2 in advance (like the one pictured above) if you don’t already have one.
  • If you have a second corded phone in another location in your house, then you’ll need to order a free adaptor. Text ADAPTOR to 61998 or visit
  • If it’s not convenient to use your corded phone near your Hub, then BT will send you a free cordless handset with instructions on how to wirelessly pair it to your Hub. Text HANDSET to 61998 or visit
  • However, unlike with the copper network, in the event of a power cut or your broadband fails, you won’t be able to make calls, including 999 calls. BT recommends that you have a mobile phone as a back-up.
  • Ofcom has also made it a requirement for telecoms providers to identify vulnerable people who are reliant on their landline and provide them with a free back-up option in case there's a power outage. 

Medical pendants and burglar alarms

Carelines and burglar alarm companies have been aware of the impending switch over for a few years now and have been working on solutions to ensure all is compatible.

Don’t worry though, when you receive a letter about Switch Over Day from BT then contact your medical pendant or burglar alarm provider to check whether the device will work with the new Digital Voice system and they will advise what you need to do in preparation.

You might also want to let your telecoms provider know you have a medical pendant that needs the landline. They may then delay moving you to the Digital Voice system to allow you the time to confirm that the device will continue to work.


If you have any issues or queries on Switch Over Day, call BT on 0800 800 150 or visit

Got a project in mind? Please contact us for a site survey and quote.

About Millrose
Millrose provides fibre and copper data cabling, WiFi, and telecom services across Cambridgeshire, Suffolk, Norfolk, Herts and Essex.

Millrose Telecom Ltd, t/a Millrose. Company Number: 09005041
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