Will my digital landline work in a power cut?

Why the old landline worked in a power cut

Copper phone lines carried their own power from the telephone exchange. A corded phone plugged into the wall socket worked even with the electricity off.

Why digital landlines don't

The UK is moving every home to digital phone lines, and the copper network closes on 31 January 2027. A digital landline (sometimes called Digital Voice) plugs into your broadband hub, and the hub runs on mains power. In a power cut the hub goes off, and so do your dial tone, your Wi-Fi and any telecare or pendant alarm that calls through the line.

What providers must offer

Providers must offer a free solution to customers who depend on their landline, but it only has to keep the phone working for at least 1 hour. If you qualify, ask your provider. Everyone else usually pays around £85 to £150 for a basic battery unit.

How to keep your phone working

• Fit a battery backup between the hub and its plug. LineKeeper™ gives 4+ hours and switches over in 0 seconds.
• Keep 1 corded phone plugged into the hub, because cordless bases need mains power.
• If you have a pendant alarm, test it with your alarm provider after fitting.
• Keep a charged mobile as a second option, though masts can lose power too.

Who should act first

Older people living alone, anyone with a telecare alarm, rural homes on overhead lines and anyone with weak mobile signal. See our guide to battery backup for elderly parents.