What to do in a power cut, hour by hour

By SGWNI. Checked on 2 November 2026.

In a power cut, first check whether it’s only your home: ask a neighbour, and look at your trip switch. If the street is out, report it online or call 105 for free (03457 643643 in Northern Ireland). Then keep the fridge and freezer shut, switch off anything that shouldn’t come back on unattended, and leave one light on so you’ll know when the power returns. After that, what you do depends on how long it lasts.

The first 15 minutes

Light. Use a torch rather than candles. Be Ready says torches are safer.
Is it only you? The Energy Networks Association says that if your neighbours have power, your trip switch may have activated.
Report it. Enter your postcode at powercut105.com to find your network operator. Its website and social media pages have updates and repair times. If you can’t get online, call 105.
Switch things off. Turn off irons, ovens, electric fires and fryers. Unplug your TV and computer to protect them from a surge when the power returns.
Leave one light on, so you’ll see when it’s fixed.
Note the time. It decides what happens to your food later.

If you see a damaged power line, keep well away and keep other people away. Call 105. If someone is in immediate danger, call 999.

The first hour

Keep the fridge and freezer closed. Opening the door lets warm air in.
Save your phone battery. You may lose internet, and possibly mobile signal.
Check on neighbours, particularly anyone older or living alone.
Find the radio. Try FM and digital. A car radio is another option.
If you depend on medical equipment, switch to your battery plan now. Be Ready says people on the Priority Services Register can get priority support in an emergency.

A corded landline may still work. If you have no working phone and face a life-threatening emergency, call 999 or 112 from any mobile. Emergency calls can connect through other networks.

Hours 1 to 4

Some cuts end here. In a national energy shortage, rota cuts would typically last about three hours at a time, but a fault or a storm can take longer.

Stay warm with layers and blankets.
Use up what’s already out of the fridge before opening anything else.
If you have a fridge thermometer, check it once, quickly.

At 4 hours: the fridge

The Food Standards Agency says a fridge should stay cold for up to 4 hours. During a power cut, chilled food is acceptable below 8°C. If the fridge has reached 8°C or above, eat foods that need a fridge within 4 hours, then throw away what’s left, unless the power comes back within that time.

Without a thermometer, you can’t tell. Treat chilled food as at risk once 4 hours have passed. If in doubt, throw it out, and never taste food to check.

Young children, pregnant women, older people and people with health conditions are at higher risk of food poisoning, so take more care. The FSA’s order for eating is:

Food that needs a fridge.
Defrosted frozen food that doesn’t need cooking.
Perishable food kept at room temperature.
Tinned, bottled and dried food.

The power cut food checker runs a countdown from the time your power went off and goes through your food item by item.

The evening and overnight

Keep warm. Get everyone into one room and close the doors of the rooms you aren’t using. Close the curtains at dusk, and put towels under doors. Wear several thin layers.
Watch for the cold. Older people, babies, young children and people with long-term health conditions are most at risk. Signs of hypothermia include shivering, cold skin, slurred speech, and tiredness or confusion. It’s a medical emergency: the NHS says to go to A&E or call 999 if you think someone has it.
Cook safely. The FSA says to use a camping stove, barbecue or bottled gas stove only if the manufacturer allows it, and to make sure food is steaming hot. Never use camping stoves or barbecues indoors. The Chief Medical Officers warn that carbon monoxide can kill.
Generators. Never run one indoors. Keep it outdoors, at least 6 metres from buildings, with the exhaust away from doors and windows.
Babies. Ready-to-feed formula is safest, because powder needs freshly boiled water.
Water. Mains water may be affected too. Keep stored water for drinking, handwashing and preparing food.

If you smell gas or suspect carbon monoxide, call the gas emergency number: 0800 111 999, or 0800 002 001 in Northern Ireland. If you think someone has carbon monoxide poisoning, the NHS says to stop using the appliance if you can, go outside and get medical advice. Call 999 if they’re struggling to breathe, confused, weak or unconscious.

Hours 12 to 24

You may be entitled to compensation. In Great Britain, the Energy Networks Association says your network company has 12 hours to restore power if fewer than 5,000 premises are affected by the fault, and 24 hours if more are. Severe weather has different rules. Payment is usually automatic.

A half-full freezer should keep food frozen for about 24 hours, according to the FSA. Check the time, keep the door shut, and don’t open it to look.

If you have medicines that need a fridge, ask your pharmacist what to do. Don’t guess.

Hours 24 to 48

A full freezer should keep food frozen for up to 48 hours. The FSA says these are estimates, and the real time depends on your freezer’s make and model.

Be Ready asks for 3 days of supplies, so this is when they matter. Keep checking on neighbours and share what you can.

When the power comes back

Turn things back on a few at a time.
Check the fridge temperature, and how long it was off.
Refreezing. Don’t refreeze food that has thawed. The FSA’s power cut advice doesn’t cover this, but Food Standards Scotland says not to refreeze food that thawed while the power was cut, and the FSA’s general advice is to use defrosted food within 24 hours. Food that’s still frozen solid hasn’t thawed, so it can stay in the freezer. US advice is more relaxed about food with ice crystals, but we follow the UK rule, as the power cut food checker does.
Replace what you used, and make a note of what you wished you’d had.

Getting ready for next time

Keep a torch, a radio and a charged power bank somewhere you can find them in the dark, along with 105 and your other numbers on paper. Find your load block letter at powercut105.com. If anyone relies on powered equipment, our power station runtime calculator estimates how long a battery would last. If you could need extra help, check the Priority Services Register.