Power cut guide
What to Check When the Power Comes Back On
Quick answer: When the power comes back on, switch appliances back on a few at a time, check anything that heats up, and look at your fridge and freezer before eating anything. If chilled food has been at 8°C or above for more than 4 hours, throw it out. Then reset your heating, clocks and timers, restart your router, and if your neighbours have power but you don’t, check your trip switches and call 105.
Is the power off where you are? See live power cuts from the network operators and reports from neighbours.
The lights flicking back on is a relief, but a few minutes of checking can save you a ruined freezer, a cold house overnight or a missed alarm in the morning. This checklist works through the jobs in a sensible order, from safety first to the small resets people tend to forget.
Your first five minutes
Start with anything that could be a fire risk or that someone depends on.
- Check the cooker, hob, iron, heaters and hair tools. If you didn’t switch them off at the start of the cut, they may have come back on. Councils and fire services both point out how easy it is to forget what was left switched on.
- Check any medical equipment such as oxygen concentrators, feeding pumps or powered beds. Make sure it has restarted properly and begin recharging backup batteries.
- Blow out any candles and switch off camping stoves or other temporary heat sources. Put a generator away once it has cooled down.
- Plug sensitive electronics back in, such as TVs and computers, once the supply has been steady for a few minutes.
- Switch things on gradually rather than all at once. If something trips your consumer unit again, you’ll know which appliance to look at.
Safety: If you smell gas when the power returns, don’t touch light switches or electrical appliances. Open the windows, leave the property and call the gas emergency line on 0800 111 999 (Great Britain) or 0800 002 001 (Northern Ireland).
Protecting appliances and electronics
Network operators and fire services advise unplugging sensitive equipment during a power cut, and this is the main reason why. When supply is restored, and particularly if it goes off and on again a few times while engineers work, delicate electronics are better off disconnected until it settles.
- Computers: save your work and shut down properly if the power is flickering. Check that files you were working on saved correctly. Our guide to power cuts and working from home covers protecting devices and data in more detail.
- TVs and set-top boxes: some will need to retune or download updates. Give them a few minutes.
- Washing machines and dishwashers: a programme that stopped part-way may restart, wait for you, or need cancelling. Check the door is safe to open and the drum isn’t full of water before you open it.
- Electric vehicle chargers and smart plugs: check schedules haven’t reset to default.
If an appliance won’t come back on, check its plug fuse and the consumer unit before assuming it is broken. If you think the fault on the network damaged something, keep the item and any repair quotes, and speak to your home insurer.
Food in the fridge and freezer
This is the check that matters most for your health. The Food Standards Agency and Food Standards Scotland give clear figures.
| Appliance | How long it keeps food safe with the door shut | What to check |
|---|---|---|
| Fridge | Up to about 4 hours | Is it still below 8°C? Chilled food that has been at 8°C or above for more than 4 hours should be thrown away. |
| Full freezer | Up to about 48 hours | Is food still frozen solid? |
| Half-full freezer | About 24 hours | Is food still frozen solid? |
These are estimates, and real times depend on your appliance and how warm the room is. A power cut of less than 4 hours is unlikely to affect food safety, provided you kept the doors shut.
- Use a fridge thermometer if you have one. A normal fridge should be at 5°C or below.
- Throw away chilled food such as meat, fish, dairy, cooked leftovers and anything labelled “keep refrigerated” if the fridge reached 8°C or above for more than 4 hours.
- Food that has fully defrosted should be used within 24 hours. The FSA says you can freeze food again once it has been cooked, but you should only reheat it once after that.
- If you’re not sure, throw it out. Food poisoning is a much bigger problem than a lost meal.
Our full guide on how long food lasts in the fridge and freezer in a power cut covers high-risk foods, baby milk and medicines that need refrigerating.
Tip: Before you throw food away, take photos of it and make a quick list. If you claim on home insurance, this makes the claim much easier.
Heating, hot water and boilers
Most central heating systems need electricity for the pump, controls and ignition, even if they run on gas or oil. When power returns, the heating doesn’t always restart by itself.
- Check the boiler display for a fault code or warning light. Many boilers have a reset button. Use it only as the manufacturer’s manual describes.
- Check the timer and thermostat. Some lose their settings or show the wrong time.
- If the boiler won’t restart after a reset, or keeps locking out, call a Gas Safe registered engineer (or OFTEC-registered for oil). Don’t take the casing off yourself.
- If you have a heat pump, check its controller for error messages and that your schedules are still set.
Our guide to boilers, heat pumps and heating after a power cut has step-by-step help for common problems.
Clocks, alarms and everything else that resets
A short walk around the house now saves surprises later. Here is a checklist:
- oven, microwave and other appliance clocks
- alarm clocks without a backup battery (set a phone alarm for the morning if you rely on one)
- burglar alarm panels, which may show a fault or need resetting with your code
- broadband router and Wi-Fi: if your internet doesn’t come back within a few minutes, turn the router off and on again
- digital landline phones, telecare alarms and pendant alarms: check they have reconnected
- mains-powered smoke and carbon monoxide alarms: check any power light is showing and press the test button
- garage doors, electric gates and doorbells
- fish tank heaters and pumps, and any timers on lights or plants
- chargers: start recharging phones, power banks, torches and battery lights so you’re ready if it goes off again
Tell people the power is back
Network operators restore supplies in stages, and they rely on reports to know which homes are still off. If you reported the power cut on 105, there’s no need to call again just to say it’s back. But if you see neighbours still in the dark, encourage them to report it.
On UKPowerCut.com you can check your postcode and tap “Power is back” so neighbours can see that supplies are returning in your area. It helps others judge whether their own problem is part of the wider cut. You can also see whether any nearby areas are still affected on our power cuts today page.
It’s worth checking in on older or vulnerable neighbours too, especially if the cut was long or cold. Make sure their heating has restarted and their food is safe.
Neighbours have power but you don’t
If the street lights are on and next door has power but your home is still dark, the problem is probably limited to your property. Work through these steps.
- Check your consumer unit (fuse box). Look for any trip switch or RCD in the “off” position. A faulty appliance can trip a switch when the supply returns.
- Unplug everything and try resetting the switch. If it stays on, plug appliances back in one at a time to find the culprit.
- If the switch won’t stay on even with everything unplugged, call a qualified electrician.
- If nothing is tripped and nothing works, call 105 (or NIE Networks on 03457 643 643 in Northern Ireland). The problem may be the operator’s main fuse or the cable to your home.
Our guide on checking your fuse box and trip switch shows what to look for and how to reset a tripped switch safely.
Safety: Never open or touch the sealed main fuse (service cut-out) or the meter. They belong to the network operator and your supplier, and only they can work on them.
If the operator’s fuse has failed, there is a standard for how quickly they must attend. In Great Britain, if they don’t arrive within 3 hours on weekdays (7am to 7pm) or 4 hours at weekends and on bank holidays (9am to 5pm), you’re entitled to a £40 payment.
Check whether you’re owed compensation
If you were off for a long time, you may be entitled to a guaranteed payment from the network operator. In normal weather, homes in Great Britain are due £100 after 12 hours without power, plus £45 for each further 12 hours, with different rules for very large incidents and severe storms. Most payments are made automatically, but it’s worth keeping a note of when the power went off and came back.
Our power cut compensation page explains the amounts and how to chase a payment if it doesn’t arrive.
Frequently asked questions
Should I unplug appliances when the power comes back on?
It’s best to unplug sensitive electronics during the cut, then plug them back in once the supply has been steady for a few minutes. Switch other appliances on a few at a time so you can spot a fault if something trips.
Why has my boiler not come back on after the power cut?
Many boilers go into a lockout or lose their timer settings when the power goes off. Check the display, reset the timer and use the reset button as your manual describes. If it still won’t fire up, call a Gas Safe registered engineer.
Is food in the freezer safe after a power cut?
A full freezer should keep food frozen for up to about 48 hours, and a half-full one for about 24 hours, if the door stays shut. Food that has fully defrosted but stayed cold should be used within 24 hours, or cooked and then frozen again. Raw food that has thawed should not go back in the freezer uncooked.
The power came back but went off again. What should I do?
This often happens while engineers test and switch parts of the network. Keep appliances switched off, keep the fridge and freezer shut, and follow the usual power cut steps. If it keeps happening over weeks or months, you may be entitled to a payment for multiple interruptions.
Your next step: once everything is back to normal, restock your torch batteries and charge your power banks, so you’re ready for the next one. It only takes a few minutes, and you’ll be glad of it next time.
Sources
- Food Standards Agency u2013 Food safety in a power cut: advice for consumers
- Food Standards Scotland u2013 Power cuts
- Food Standards Agency u2013 How to chill, freeze and defrost food safely
- County Durham and Darlington Fire and Rescue u2013 Safety advice in the event of a power disruption
- Dudley Council u2013 Power cuts
- Ofgem u2013 Check if you can get a payment for a power cut
Checked against these sources on 28 October 2026. Rules and amounts can change – your network operator or Ofgem has the final word. Spotted something out of date? Tell us.
More on during a power cut: What to Do in a Power Cut: The Complete UK Guide · All power cut guides