Will My Boiler, Gas Hob and Wi-Fi Work in a Power Cut?
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The quick answer
Your gas boiler stops (heating and hot water). Your gas hob usually still works if you light it carefully with a match. Wi-Fi and digital landlines stop, and mobile signal may drop after a few hours. Tap water normally keeps running, and a full freezer stays frozen for about 48 hours if you keep it shut.
When the power goes, the first questions are always the same: Can I still put the kettle on? Will the heating come back? Can the kids still get online? Here’s what keeps working and what doesn’t, with a fix for each.
At a glance
| Thing | Works in a power cut? | Simple fix |
|---|---|---|
| Gas combi or system boiler | No | Keep warm in one room; flasks of hot water |
| Oil boiler | No | As above |
| Gas hob | Usually (light with a match) | Long matches or a gas lighter in the kitchen drawer |
| Gas oven | Often not (electronic ignition or controls) | Use the hob instead |
| Electric or induction hob, microwave, kettle | No | Gas hob, or a flask filled before the storm |
| Wi-Fi router | No | Router battery backup or power station |
| Digital landline | No (unless battery backup) | Ask your provider for the free backup if you rely on it |
| Mobile signal | For a while | Keep phones and power banks charged |
| Tap water | Usually | Some flats with booster pumps lose water, so store a few litres |
| Fridge and freezer | Stay cold if you keep them shut | Fridge about 4 hours, full freezer about 48 hours |
| Electric shower, heat pump, storage heaters | No | – |
| Open fire or wood burner | Yes | Only with a working carbon monoxide alarm |
Your boiler: why the heating stops
Almost every modern gas boiler, whether it’s a Worcester Bosch, Vaillant, Baxi, Ideal or anything else, needs electricity for its controls, ignition, fan and pump. So even though gas is still reaching your house, the heating and hot water stop the moment the power goes. Oil boilers are the same.
What you can do:
- Fill flasks with boiling water when a storm is forecast, for hot drinks and hot water bottles.
- Keep heat in: pick one small room, close doors and curtains. See our guide on how to keep warm in a power cut.
- If you have a hot water cylinder, the water in it stays warm for several hours, so use it for washing.
When the power comes back, most boilers restart on their own. If yours shows a fault code or won’t fire up, check the manual or the manufacturer’s website for how to reset it. Most have a reset button. If it still won’t start, call a Gas Safe registered engineer rather than taking the cover off.
Running a boiler from a generator or power station: boilers are usually wired into a fused spur, not a plug, so connecting one to backup power safely needs a qualified electrician. Never back-feed power into your house wiring.
Your gas hob: usually yes, with a match
In a power cut the gas supply normally keeps flowing, so on most gas hobs you can still cook:
- Light a long match or gas lighter first.
- Push in and turn the knob, and hold the flame to the burner.
- Keep the knob pressed in for 5–10 seconds after it lights. This lets the flame safety device warm up, so the gas stays on.
Hobs and ovens with electronic controls or touch panels won’t work, and many gas ovens won’t either. Induction and electric hobs, kettles and microwaves are out until the power returns.
Never use the hob or oven to heat the room, and keep a window open a crack while cooking. If you smell gas, don’t light anything. Get outside and call 0800 111 999 (free, 24 hours).
Wi-Fi and the internet: off, unless you plan ahead
Your router needs mains power, and on full fibre so does the small box on the wall where the fibre comes in. When the power goes, so does your Wi-Fi, even if the street cabinet down the road is still running.
The fix is cheap: a router battery backup (a mini “UPS” that sits between the plug and the router) can keep it going for several hours. Some broadband providers now offer their own. A router uses only about 10W, so a small power station can keep it running for most of a day. Use our power cut calculator to check.
Browse router battery backups on Amazon
It only helps if the wider network still has power, which is often the case in local cuts but not always in big storms. So keep phones charged too.
Landlines: the one to check for older relatives
Most UK landlines have now moved, or are moving, to digital phone lines, which run through your router. That means a digital landline stops working in a power cut unless it has a battery backup.
Ofcom requires providers to offer a free backup solution giving at least one hour of emergency calling to customers who depend on their landline, for example people with no mobile phone or no mobile signal at home. If that’s you, or a parent or grandparent, ask the provider now, before the next storm.
Mobile signal: it works for a while
Mobile masts need power too. Many have batteries, but these last anywhere from under an hour to several hours, and some masts have no backup at all. In a long cut, signal and mobile data can fade. So:
- Keep phones and power banks charged when a storm is forecast.
- Turn on low-power mode, and turn screen brightness down.
- Save 105 (power cuts) in your phone, and write it on paper too.
- A battery or wind-up FM radio keeps you informed even when the internet doesn’t.
Water, fridge and freezer
- Tap water normally keeps running, because water companies have their own backup power. Some flats and tall buildings use electric booster pumps, so keep a few litres stored just in case.
- Fridge: stays cold for about 4 hours if you keep the door shut.
- Freezer: a full one stays frozen for about 48 hours (about 24 if half full). Don’t keep checking it.
Get ready in 10 minutes
- Long matches or a gas lighter in the kitchen drawer
- Flasks ready to fill when a storm is forecast
- Phones and power banks charged
- 105 saved in your phone and written on paper
- Battery backup for the landline if anyone relies on it
- Carbon monoxide alarm if you have a gas, oil or wood appliance
See what else is worth having with our kit budget builder, and if the power was off for a long time, check what you’re owed with the compensation calculator.
Frequently asked questions
Does a gas boiler work in a power cut?
Almost certainly not. Modern gas combi and system boilers (Worcester Bosch, Vaillant, Baxi, Ideal and the rest) need electricity for their controls, ignition, fan and pump, so heating and hot water stop when the power goes. Oil boilers stop too. Hot water already in a cylinder stays warm for a while.
Can I use my gas hob in a power cut?
Often yes. The gas supply usually keeps flowing in a power cut, so on most gas hobs you can light a burner carefully with a match or long lighter, then hold the knob in for a few seconds so the safety device stays open. Hobs and ovens with electronic controls won't work. Never use a gas oven or hob to heat the room, and keep a window open a crack.
Does Wi-Fi work in a power cut?
No. Your router needs mains power, and with full fibre the box on the wall where the fibre comes in needs power too. A small battery backup for the router, or a power station, can keep home Wi-Fi going if the local network still has power.
Does my landline work in a power cut?
Digital landlines, which have replaced most old copper lines, stop working in a power cut unless you have a battery backup. Ofcom requires providers to offer a free backup giving at least one hour of emergency calling to customers who depend on their landline. Ask your provider if that's you or someone you care for.
Does mobile signal work in a power cut?
For a while. Many mobile masts have batteries that last anywhere from under an hour to several hours, and some have none, so signal and mobile data can drop in longer cuts. Keep your phone charged and use it sparingly.
What should I do if I smell gas?
Don't light anything or use electrical switches. Open doors and windows, turn off the gas at the meter if you can, get everyone outside and call the free National Gas Emergency number, 0800 111 999 (England, Scotland and Wales), from outside the house.