Britain’s old copper telephone network is being retired. By 31 January 2027, every home phone line in the UK is due to run on digital technology (VoIP) instead of the analogue Public Switched Telephone Network that has carried calls since the 1980s. For most households this is a non-event — a box gets swapped, the dial tone sounds the same. For anyone relying on a pendant alarm, pull-cord, or fall detector that dials out over the landline, it is a different story: several of these devices simply stop working when the line beneath them changes character, and there have already been documented cases where an analogue telecare unit failed to raise the alarm after a switchover with serious, even fatal, consequences. This is precisely the kind of thing an independent household should be told plainly, not left to discover the hard way — so here is what actually changes, and what to do about it.
Why an alarm that worked yesterday can fail tomorrow
Most personal alarms fitted before the last few years were built for an analogue line: a continuous electrical circuit that carries both power and a distinctive signalling tone the alarm unit is designed to recognise. Digital Voice services carry calls as data over broadband instead, and the tones, timing and call-setup behaviour are different enough that older alarm hardware can misread them or fail to connect at all. The device may still light up, still appear to work when you press the test button — and still fail silently the one time it actually needs to dial the monitoring centre. That gap between "looks fine" and "works when it matters" is the whole reason this deserves attention now, while there is still time to check, rather than after an engineer has already swapped the line.
The power cut problem nobody mentions
There is a second, less obvious change. A traditional analogue line carries its own low-voltage current down the copper wire, which is why an old phone kept working in a power cut even when the lights went out. A digital line depends on your router and an internet connection, both of which need mains electricity. Lose power at home and, without a battery backup, your landline — and anything plugged into it — goes dead at exactly the moment a fall or a medical emergency is most likely to happen unnoticed by anyone else. Regulators have required phone providers to guarantee at least one hour of backup power for emergency calls, and several providers have said they will go further for customers identified as vulnerable, but that protection only reaches people the provider actually knows about.
What to check before your line is switched
The practical response is not complicated, but it does require you to make the first move rather than wait for a letter to arrive.
- Tell your telecare provider you are being switched. Whoever supplies or monitors the alarm — a local authority community alarm service, a charity scheme, or a private provider — needs to know the make and model of the unit in use so they can confirm compatibility with a digital line, or arrange a replacement device before the old line is disconnected, not after.
- Tell your phone or broadband provider separately. Landline providers are expected to flag telecare users and hold off migrating that line until compatibility is confirmed, but that only works if the household is flagged in the first place. A phone call naming the alarm explicitly is worth more than assuming the provider already knows.
- Ask about a digital-ready alarm rather than an adaptor. An adaptor can sometimes bridge an old analogue unit onto a digital line, but a unit designed for digital signalling from the outset, or one that uses its own SIM card independent of the household phone line entirely, removes the compatibility question altogether.
- Ask specifically about power-cut cover. Confirm what backup exists for the router and the alarm base unit if the mains fails, and how long it lasts, rather than assuming the standard household broadband backup automatically covers a telecare device plugged into it.
- Keep a written note of who you told and when. If a fault does occur after a switchover, a record of having flagged the alarm in advance makes any subsequent complaint or compensation claim considerably more straightforward.
Old line versus new line, at a glance
| Feature | Analogue (PSTN) line | Digital Voice (VoIP) line |
|---|---|---|
| Power source for the phone line itself | Carried down the copper wire | Relies on mains-powered router and broadband |
| Behaviour in a power cut | Kept working independently | Fails without a battery backup unit |
| Older analogue alarm compatibility | Full compatibility by design | Not guaranteed — can fail silently |
| What is needed to stay safe | Nothing — status quo | Provider confirmation, possible device swap, backup power check |
Watch for the scam that rides on the back of a genuine switchover
Because the switchover is real, ongoing and genuinely requires households to take action, it is also an obvious opening for opportunists. A genuine landline provider will never ask a customer to pay to be moved onto a digital line, and will not demand payment or bank details over an unsolicited phone call to “secure” a telecare connection. Anyone who calls asking for money to complete the switch, or pressures an older or vulnerable resident into an immediate decision, should be treated as a scam and reported rather than engaged with. Genuine engineer visits and equipment swaps are arranged through the account holder’s own provider, at no extra charge for the switchover itself.
The underlying point
This is a case where staying independent at home depends on a piece of infrastructure most people never think about twice a decade. The right response is not panic and it is not to ignore the letters that arrive about it — it is to ask two direct questions, of two different organisations, well before any switchover date is set for your address: does my alarm still work on a digital line, and what happens to it in a power cut. Getting clear, specific answers to both is worth more than any reassurance that "most people won’t notice a difference" — because the households where it does make a difference are precisely the ones this matters most for.