Landline Switch-Off, 31 January 2027: What Stops Working in a Small Business
Your phones will be fine. The alarm dialler, card terminal, lift line and door intercom are what to check before January.
On 31 January 2027 BT switches off the analogue phone network, the PSTN, and every landline in the UK moves to voice over broadband. The handset will be fine. What breaks in a small business is the equipment that dials out over copper: the alarm panel, older card terminals, the lift emergency line, door intercoms and the fax.
In short
- The analogue phone network (PSTN) is switched off on 31 January 2027; after that a phone line is a broadband service, and anything that dials over copper needs changing.
- An alarm panel that calls a monitoring centre or your mobile needs an IP or 4G communicator, about £150 to £350 fitted, and only your alarm company can change it.
- A digital phone line dies in a power cut: a small UPS (£80 to £200) keeps the router, phone adapter and alarm communicator alive, and a 4G failover router (£200 to £400) keeps card payments running when the broadband fails.
- Alarm and lift companies will be booked solid by December, so list every device on a phone socket and book them now.
What changes on 31 January 2027
The PSTN is the copper network that has carried calls into British buildings for a century. BT is retiring it on 31 January 2027. The date was originally December 2025 and was pushed back in May 2024. Do not plan on another delay: most providers have already moved most of their customers, and the new date is the hard stop.
After the switch your phone number stays the same, but the call travels over your broadband connection instead. BT calls this Digital Voice; other providers have their own names for the same thing. The handset plugs into the router or a small adapter, and ordinary calls feel no different.
The catch is that the old network did two jobs nobody thinks about. It carried the tones that alarm panels, card terminals and lift phones use to dial out, which digital lines handle badly or not at all. And it carried its own power from the exchange, which is why a corded phone worked in a power cut. Both go in January.
The devices that stop working
Look for anything plugged into a phone socket that is not a telephone. In the shops, salons and workshops we fit networks for, this is the list that keeps turning up.
| Device | After the switch-off | Fix | Typical cost |
|---|---|---|---|
| Alarm panel dialler (monitoring centre or your mobile) | Fails or connects unreliably | IP or 4G communicator fitted by your alarm company | £150 to £350 fitted |
| Card terminal that dials out | Stops | WiFi or 4G terminal from your payment provider | Ask the provider; often a swap |
| Lift emergency phone | Stops, and it must keep working by law | GSM or IP unit fitted by the lift company | Quoted by the lift company |
| Door-entry or gate intercom that rings a phone | Stops | 4G or IP intercom; cabling by us | Quoted at the survey |
| Fax and franking machines | Dial-up models stop | Email, online fax, or an internet-connected franker | Usually a small monthly fee |
| Telecare pendants in a care setting | May fail silently | Digital or mobile-network unit from the telecare provider | Varies by provider |
| Till or EPOS dial-up fallback | Stops | Broadband with a 4G failover router | £200 to £400 |
| Any digital line in a power cut | Stops until the power returns | Small UPS for the router, adapter and communicator | £80 to £200 |
The alarm is the one that catches people out. A monitored alarm reports to the control room over the phone line, and many unmonitored panels ring the owner's mobile. On a digital line that call may connect, garble or fail silently, and the panel looks exactly as it did before. Your alarm company has to fit the communicator, because it means reprogramming the panel. Ring them early.
Card terminals are the next most common. An older countertop terminal that dials out through a phone socket needs replacing with a WiFi or 4G model from your payment provider. The lift emergency line is a legal requirement, so the lift maintenance company must fit a GSM or IP unit. Fax and franking machines mostly go into retirement. In a care setting, telecare pendants are the same story as the alarm; we covered those in our guide to the switch-off and care alarms.
The risk nobody mentions: power cuts and broadband failures
A copper phone worked in a power cut because the exchange powered it. A digital line does not. When the electricity goes off, so does the router, and with it the phone, the alarm communicator and everything else on the broadband. Ofcom only requires providers to offer battery backup to customers who depend on the landline, and only for about an hour, so a business must sort this out itself.
The fix is a small uninterruptible power supply (UPS), about £80 to £200 at the time of writing. The router, phone adapter and alarm communicator plug into it, and it carries them through a few hours without mains. We fit one as standard on business networks.
Broadband failing is the more common problem, and it now takes the phones and the card machine with it. A 4G failover router (£200 to £400) takes over within seconds when the broadband drops, on a cheap data SIM, so card payments keep going, the phone keeps ringing and the alarm stays connected. We explain how this fits into a shop or office network in our small business WiFi guide.
What to do now
- List every device on a phone socket. Alarm panel, card terminal, lift phone, intercom, fax, franking machine, till modem, telecare unit. Note the make and model of each.
- Ask your provider which line you are on. If the phone still plugs into the wall socket rather than the router, you have not been moved yet.
- Book the alarm company and the lift company this month. They have thousands of these to do and the diaries will be full by December.
- Decide what must survive a power cut and a broadband outage, and size the UPS and the failover to match.
- Test everything after the switch. Set the alarm off on purpose and check the call arrives, run a card payment, press the lift button, ring the intercom. Then repeat a week later.
What we can and cannot help with
We do not install intruder alarms or lift equipment, and will not pretend otherwise. For the alarm, ring the company whose sticker is on the bell box; for the lift, the maintenance contractor named on the certificate in the car. Both will know what the switch-off means for your model.
What we do is the network underneath: a business router with UPS and 4G failover, and cabling to wherever the new IP intercom, access control and cameras need it. Our business WiFi and networking page covers the kit. Commercial CCTV runs on the same cabling and the recorder sits on the same UPS, which we go through in our post on CCTV for a small business. If you want someone to walk the premises and say which socket feeds what, the business survey is free.
Get the network ready before January
We fit business networks with battery backup and 4G failover across Sussex, and the free visit is a good moment to list what else is still on copper.
Book a Free SurveyFrequently Asked Questions
Will my business phone number change when the landline is switched off?
No. Your number moves across to the digital service with you, and callers notice nothing. What changes is the plumbing: the handset plugs into the router or a small adapter instead of the wall socket. If you change provider at the same time, ask for the number to be ported before the old line closes; recovering a lost number afterwards is slow.
Is the 31 January 2027 date likely to move again?
Plan as if it will not. The date was already pushed back once, from December 2025, in May 2024, to give providers more time with vulnerable customers. Most lines have been moved since then and the rest are being switched in batches through 2026. Your provider may move you months before January, so the real deadline is whenever your letter arrives.
Does the landline switch-off affect my broadband?
Not directly. The switch-off retires the analogue voice service, not the copper cable, so a broadband connection that runs over copper (the usual fibre-to-the-cabinet service) keeps working. What changes is that the phone now rides on the broadband, which is why a broadband outage or a power cut takes the phone, the alarm and the card machine down together.
Can I still take card payments if the broadband goes down?
Only if you have planned for it. A 4G failover router, about £200 to £400 at the time of writing, takes over within seconds when the broadband drops, so the terminal carries on. A simpler fallback is a 4G card terminal from your payment provider, which does not depend on the shop broadband at all. Having both is sensible if most of your takings are by card.