Every few weeks now a business owner asks me some version of the same question: “is it true the phone lines are being switched off?” Yes, it is, and the deadline is closer than most people realise.
In short: the UK’s old analogue phone network, the PSTN, is being retired and fully replaced by digital, all-IP connections by 31 January 2027. Anything that runs over a traditional copper phone line, your phones, but also alarms, lifts, door entry and some card machines, needs to move to a digital service before then. Here is what is changing, what to check in your business, and how to switch without the drama.
Key takeaways
- The analogue phone network (PSTN and ISDN) is being switched off across the UK by 31 January 2027.
- It is not just desk phones. Alarms, lift lines, door entry, card machines and some CCTV often rely on the same copper line.
- The replacement is digital voice over your internet connection, and for most teams that means Microsoft Teams Phone inside the Microsoft 365 you already have.
- The real risk is leaving it late, when good install slots get scarce and a forgotten alarm or lift line stops working.
- The fix is a simple audit now, then a planned move, so nothing important goes quiet on the day.
What is the PSTN switch-off?
The PSTN, the Public Switched Telephone Network, is the traditional copper phone system that has carried calls for decades. Alongside it sits ISDN, the older business phone-line technology. Both are being retired. After the switch-off, calls travel over your internet connection rather than a dedicated phone line. You may hear it called all-IP, VoIP or Digital Voice. It is the same idea: the line in the wall stops being a phone line and becomes data.
When is the deadline, and why did it move?
The full switch-off is set for 31 January 2027. The original target was December 2025, but it was pushed back after concerns that vulnerable people and critical services, things like telecare alarms, were being moved across too quickly. The extra time is not a reason to relax. It is a reason to plan properly, because the work still has to happen and the closer we get, the busier installers become.
What in your business actually relies on the old network?
This is the part that catches firms out, because it is rarely just the phones. On a single copper line you might also find:
- Fire and intruder alarms that dial a monitoring centre
- Lift emergency phones
- Door entry systems and electric gates
- Card machines (PDQ) on an analogue line
- Fax machines, and CCTV that dials out
If any of those quietly stop working on switch-off day, you have a safety and compliance problem, not just an inconvenience. The honest first step is a proper audit of everything plugged into a phone line, not a guess.
What are your options when the line goes digital?
For the phones themselves, most businesses of small businesses up to 100 staff are best served by digital voice that runs through software, so your team can call from a laptop, a desk handset or a mobile, all on the same number. For the firms we look after, that usually means Microsoft Teams Phone inside the Microsoft 365 you are already paying for, which keeps everything in one place and avoids a separate phone bill and a separate login.
For the non-phone devices, the alarms, lifts, card machines and the like, each one needs checking with its own supplier or moving to a modern, internet-connected equivalent. Some can move to digital as they are, some need a small upgrade, and a few need a dedicated solution. The point is to know which is which before the line changes, not after.
What should you do now?
You do not need to panic, but you do need a plan. In order:
- Audit every device and line. List everything that plugs into a phone socket, including the ones nobody thinks about.
- Check your internet. Digital voice is only as good as your connection, so make sure it is solid and has a sensible backup for call continuity.
- Plan the phone move. Decide on your digital voice setup, port your numbers, and train the team.
- Sort the non-phone devices. Get written confirmation from each alarm, lift and card supplier that they are switch-off ready.
- Do it with time to spare. Aim to be done well before the deadline, not in the final rush.
How Initial IT helps
We handle this end to end for businesses across Lichfield, Staffordshire and the West Midlands. We audit what you have, recommend the right digital voice setup (usually Microsoft Teams Phone, so it sits in your existing Microsoft 365), port your numbers, and make sure the easy-to-forget lines, the alarm, the lift, the card machine, are all dealt with. The aim is the same as always: you should barely notice the change, because we planned it. If you would like to know where you stand, book a quick chat or see what our managed IT support covers. The regulator Ofcom also publishes plain-English guidance on the move to digital landlines.
Frequently asked questions
Do I have to do anything, or will it happen automatically?
You need to act. Your provider will move the line, but they will not audit your alarm, lift or card machine, or set up your phone system the way your business needs. The planning is on you, or on an IT partner you ask to handle it.
Will my phone numbers change?
No. Your existing numbers can be ported across to digital voice, so customers ring the same number as always.
What happens to my phones in a power cut or internet outage?
Digital voice needs power and internet, so it is worth planning for. Options include mobile failover, a backup connection, and making sure any critical line, like a lift phone, has a resilient solution. We build this in rather than leaving it to chance.
Is digital voice more expensive?
Usually it is the opposite. Running calls through Microsoft Teams Phone inside your existing Microsoft 365 often removes a separate line rental and phone system, so many firms end up paying less while getting more flexibility.
How long does the switch take?
For a typical small firm the phone move is quick once planned, often a matter of days for setup and number porting. The bigger variable is the non-phone devices, which is exactly why an early audit matters.
– Andy Price, Founder & MD, Initial IT · 01543 524594 · hello@initialit.co.uk