| 12 May 2026
PSTN Switch Off 2027
The PSTN switch off is one of the biggest changes to happen to UK telecommunications in a generation. If your business still uses traditional phone lines, you need to act before January 2027. Missing the deadline will not just be an inconvenience but your phones will stop working entirely.
This guide explains what the PSTN switch off is, who it affects, what you need to do and how a trusted IT support partner like Omnia Systems can make the whole process straightforward.
Table of Contents
What Is the PSTN Switch Off?
PSTN stands for Public Switched Telephone Network. It is the old copper wire telephone network that has powered UK landlines for over a century.
BT and Openreach’s decision to switch off the PSTN is mainly due to the technology becoming out of date and expensive to operate and maintain. Openreach plans to invest instead in deploying fibre infrastructure and future-proofing the network across the UK.
In short: the old network is being retired and replaced with a fully digital one.
Who Does It Affect?
Almost every UK business. Surveys indicate that around nine out of ten UK businesses have essential services that rely on the PSTN.
You will be affected if your business uses any of the following:
- Traditional desk phones and landlines.
- ISDN lines used by office phone systems.
- Older broadband such as ADSL or FTTC. Alarm systems that dial out over a phone line.
- Card payment terminals connected via a phone line.
- Lift emergency phones.
- Fax machines.
- Door entry systems linked to a phone line.
What Replaces It?
The replacement is VoIP, which stands for Voice over Internet Protocol. It simply means making calls over your internet connection rather than a traditional phone line.
For most businesses, the practical experience is identical to a traditional phone: you pick up, you dial, you talk. The difference is what happens behind the scenes and the benefits that come with it.
Most UK businesses see a 30-50% reduction in monthly telecoms costs after migration, with eliminating ISDN line rental charges typically the single largest saving. On top of that, VoIP gives your team the ability to make and receive calls from any device, anywhere, and is ideal for hybrid and remote working.
Common Problems Businesses Run Into
Not knowing which devices are affected
Phones are obvious, but alarm systems, card terminals and lift phones are often missed entirely. A full audit of every device connected to a phone line is essential.
Leaving it too late
If you wait until late 2026, you will be queuing for engineers alongside everyone else. Businesses acting now will have far more choice and far less stress.
Worrying about losing your phone number
You can retain your existing phone numbers by migrating them to a digital VoIP service. Providers manage this process as part of the migration.
How a Managed Service Provider Can Help
For many business owners, the PSTN switch off is a significant project on top of everything else already on their plate. This is where working with a managed IT and telecoms provider makes a real difference.
At Omnia Systems, we have been helping businesses across the North West and Midlands manage their IT and communications since 2011. We work with small and medium businesses that do not have large in-house IT teams; so we understand exactly what this kind of change involves in practice.
We can audit your existing lines and devices, recommend the right VoIP solution for your business, handle the migration from start to finish and make sure nothing is missed. We also provide ongoing support after the switch, so any issues are resolved quickly.
Frequently Asked Questions
Is PSTN the Same as a Landline?
Yes. PSTN is the copper wire network set up for analogue voice communication, meaning landlines and analogue phones. If your business has a desk phone plugged into a wall socket, it almost certainly runs on the PSTN. When the switch off happens, that connection will stop working unless you have already migrated to a digital alternative.
When Is the Deadline?
The hard cut-off date is 31 January 2027, when all remaining analogue phone lines and ISDN connections will be permanently switched off.
The original deadline was December 2025, but this was delayed to January 2027 to ensure that vulnerable populations and businesses have adequate time to transition. However, that delay is not a reason to wait as BT has urged business customers to act well before the deadline.
Is PSTN Going Away for Good?
Yes. Openreach has confirmed that no further extensions will be offered. January 2027 is the final deadline.
Do Not Leave It to the Last Minute
The businesses that treat this transition as a strategic priority will emerge stronger, more efficient and better equipped for the digital future. Those who delay will face a constricting pool of available expertise and the severe operational risk of a last-minute migration.
Get Ready with Omnia Systems
The PSTN switch off affects every business using traditional phone lines in the UK.
Making the switch does not have to be complicated. With the right support, it can be handled with minimal disruption, your existing numbers kept and your business communications improved in the process.
Get in touch with the team at Omnia Systems today.
Let us manage your IT so you can concentrate on what matters most: your business.
