What to do in a power cut: before, during and after

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In a power cut, first check it isn't just your home: look at your trip switch and your neighbours' lights. Then report it, switch off or unplug anything sensitive, keep the fridge and freezer shut, and use a torch rather than candles.

Quick answer

Check your trip switch is on and whether neighbours have power. In Great Britain, call 105 free or report it online; in Northern Ireland, call 03457 643643. Turn off or unplug electronics, because power can return with surges. Keep the fridge and freezer closed, use torches not candles, save your phone and laptop battery, and stay away from fallen power lines.

Is it a power cut or just my house?

Check two things before you report anything. National Grid's power cut advice says to look at whether your neighbours' lights or the street lights are on, and to find your fuse box and check the trip switch. The trip switch is the biggest switch and is usually red.

  1. Look outside. If the street lights and your neighbours' lights are on, the fault may be inside your home.
  2. Open your fuse box and check the trip switch is in the "On" position.
  3. If it's off, turn off anything plugged into the sockets, or pull the plugs out, then switch the trip switch back on.
  4. If the power still doesn't come back, report a power cut.

How do I report a power cut?

UK (England, Scotland and Wales): call 105. It's free and connects you to your local electricity network operator, the company that runs the cables and substations in your area, which is not the same as your energy supplier. The 105 website says the quickest way to report is online, and you can find your operator by entering your postcode at powercut105.com.

UK (Northern Ireland): the UK Government's Be Ready guidance gives 03457 643643 as the number to report a power cut.

National Grid's advice is not to assume it already knows you have no power, and to contact it as soon as you can.

What should I do during a power cut?

UK: National Grid's tips are to leave one light switched on so you know when the power returns, to turn off and unplug appliances that get hot because you may forget they're on, and to keep the freezer shut. Depending on the type, it says a freezer's contents can stay frozen for up to 12 hours. Use wind-up, battery or solar torches, and don't use candles or paraffin heaters. Check on neighbours, especially anyone elderly, very ill or disabled.

US: Ready.gov says to keep fridges and freezers closed. It says a refrigerator keeps food cold for about four hours and a full freezer keeps its temperature for about 48 hours. Use a generator only outdoors, at least 20 feet from windows, doors and attached garages, and never use a gas stove or oven to heat your home, because of the risk of carbon monoxide poisoning. If the heat or cold is extreme, go to a community location that has power.

Fallen power lines: stay away from them. National Grid says to phone your network operator straight away and to phone the police if a path or road is blocked.

How do I protect my devices and my work?

National Grid says electrical surges during power cuts can damage phones, TVs, laptops and tablets, so turn them off or unplug them from the mains. Surges and surge protectors are covered in how to protect electronics from a power surge.

  1. Save your work. If you're working on a laptop, save open documents straight away. Microsoft calls the Save button "your best friend", even with AutoRecover set up, and suggests a short AutoRecover interval such as 5 or 10 minutes. For files in OneDrive or SharePoint, AutoSave saves your changes continuously.
  2. Unplug. Shut down, then unplug computers and chargers.
  3. Make your laptop battery last. National Grid suggests limiting your use of smartphones, tablets and laptops to save battery. On a Mac laptop, choose Apple menu > System Settings > Battery, then set Low Power Mode to Only on Battery. Apple says the options vary by Mac.
  4. Keep your phone charged. The FCC says you may be able to charge your phone from a charged laptop with a USB cable, though doing so may drain the laptop's battery. See how to charge your phone during a power cut.

What should I prepare before a power cut?

UK: the 105 service suggests making a plan, and reminds you that gas boilers and hobs, heat pumps, internet and phones won't work without power. The UK Government's Be Ready checklist includes a torch with spare batteries, a battery or wind-up FM radio, a charged power bank, and bottled water and non-perishable food for 3 days. If someone in your home has extra needs, sign up to the free Priority Services Register through your network operator and your energy supplier. Each keeps its own register.

US: Ready.gov suggests listing what relies on electricity and planning batteries or a power bank for it, keeping a flashlight for every household member, and installing carbon monoxide detectors with battery backup on every level of your home.

Back up your computer: on a Mac, Time Machine makes hourly backups for the past 24 hours to an external storage device, set up in System Settings > General > Time Machine on macOS Ventura 13 or later. On Windows, search for Windows Backup from the Start menu to back up your folders to OneDrive.

Medical equipment: National Grid says to make sure any medical equipment has a battery back-up. Ready.gov says to ask your medical provider for a plan for power-dependent devices and refrigerated medicines.

What should I do when the power comes back?

If your Mac won't start once the power is back, see our guide to a Mac after a power cut.

Check your food. Ready.gov's rule is "When in doubt, throw it out": throw away food that has been at 40°F (about 4°C) or higher for two hours or more, or that smells, looks or feels unusual. If the power was out for more than a day, it says to throw away medicine that should be refrigerated unless the label says otherwise, and ask your doctor or pharmacist for a new supply.

Where Failshot fits

Your password is the first layer. Failshot is the second: second layer security for your Mac, for the moment someone sits down at it and unlocks it.

While it's on, Failshot photographs whoever unlocks your Mac, then, with Pro, records a 5-second video, and its window tells them the unlock was photographed. With the Mac's built-in camera, the green light comes on. With Pro, turn on alerts and Failshot emails you about an unlock you don't confirm as yours, with the photo and the time. Switching it off, or quitting it from its menu, takes Touch ID or your Failshot PIN and answer, never your Mac password.

Failshot for Mac is a download from failshot.app, for macOS 14 or later. Free to download. It's free to use. Pro adds video, email alerts and the encrypted vault, and you can try Pro free for 7 days. The trial is on failshot.app, for the Mac. iPhone, Android and Windows are coming soon.

Banking apps down on 20 October 2026? The Google Cloud outage guide explains what Google says happened and what to do when your bank's app is down.

More questions

Is 105 free to call?

Yes. The 105 service says calling 105 is free wherever you live in England, Scotland or Wales, and it connects you to your local electricity network operator.

How long will food last in the freezer during a power cut?

National Grid says a freezer kept shut can keep its contents frozen for up to 12 hours, depending on the type. Ready.gov says a full freezer keeps its temperature for about 48 hours and a fridge keeps food cold for about four hours. Keep both doors closed.

Should I unplug my TV and computer in a power cut?

Yes. National Grid says surges during power cuts can damage phones, TVs, laptops and tablets, and Ready.gov says power may return with surges or spikes. Turn devices off or unplug them.

What is the Priority Services Register?

A free register for people with extra needs, available in England, Scotland and Wales. The 105 service says network operators can give advance notice of planned power cuts, priority support in a long power cut, and a password scheme so you know a visitor is genuine. It doesn't guarantee a continuous supply.

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