Keeping Your Landline & Router Working in a Power Cut

The short version: new digital landlines stop working in a power cut, unlike old ones. Your provider must give you at least 1 hour of backup for free. A cheap battery pack can give you much longer.

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Why this matters now

Old landlines kept working in a power cut, because they got their power down the phone line itself, not from your house.

Digital landlines don’t have that. They run through your broadband router. No electricity means no router, which means no phone line either — right when someone might need to call for help.

What you’re owed for free

By law, your provider must give vulnerable or landline-dependent customers at least 1 hour of backup power, free of charge. Some give more — Vodafone’s backup box lasts 4–7 hours.

One hour isn’t very long, though — energy comparison site UKPower found the average UK power cut lasts just over 2.5 hours. It’s worth topping this up yourself.

Two simple options

• A power bank (like a big phone charger). Cheap, and a decent-sized one can run a router for 5–10 hours. You have to plug it in yourself when the power goes.
• A UPS unit. Stays plugged in all the time and switches over automatically — nothing for you to do in the moment. Costs a bit more.

Routers use very little power — less than one old lightbulb — so you don’t need anything big or expensive.

Anker makes both types, from small power banks for a simple top-up to larger SOLIX units for longer backup.

Compare Anker’s backup options alongside whatever your provider already gives you for free.

Sources: Ofcom (General Condition A3.2(b), 1-hour minimum backup requirement); Vodafone (Broadband Battery Backup, 4–7 hours); UKPower (average UK power cut duration); independent router power measurements. Checked September 2026.