Power cut guide
How Long Does Food Last in the Fridge and Freezer in a Power Cut?
Quick answer: If you keep the door shut, a fridge should keep food safe for up to about 4 hours, a full freezer should keep food frozen for up to about 48 hours, and a half-full freezer for about 24 hours. A power cut of under 4 hours is unlikely to affect food safety. If your fridge has risen to 8°C or above for more than 4 hours, throw away chilled food such as meat, fish, dairy and cooked leftovers.
Is the power off where you are? See live power cuts from the network operators and reports from neighbours.
When the power goes off, the fridge and freezer are often the first thing people worry about, and for good reason. Bin too much and you waste money; keep the wrong thing and someone could get food poisoning. This guide uses the official figures from the Food Standards Agency (FSA) and Food Standards Scotland (FSS) to help you decide what to keep, what to eat first and what to throw away.
How long food stays safe: the key figures
These are the figures the FSA and FSS give for households. They are estimates, because the real time depends on your appliance, how full it is and how warm your kitchen is.
| Where | Safe time with the door shut | Temperature to watch |
|---|---|---|
| Fridge | Up to about 4 hours | Normally 5°C or below. During a power cut, food is OK while it stays below 8°C. |
| Full freezer | Up to about 48 hours | Food should still be frozen. |
| Half-full freezer | About 24 hours | Food should still be frozen. |
| Cupboard food (tins, jars, dried food, bread) | Not affected by the power cut | Store and eat as normal. |
The single most useful thing you can do is keep the doors shut. Every time you open the fridge or freezer, cold air escapes and the clock runs faster.
Tip: A cheap fridge thermometer takes the guesswork out of this. If it reads below 8°C, chilled food is still fine to keep.
What to do in the first hour
Say your power goes off at 6pm on a weekday. Here’s a sensible plan.
- Find out how long it might last. Check your postcode for the network operator’s estimated restoration time, or call 105.
- Keep the fridge and freezer closed. Decide what you need for dinner and take it all out in one go.
- Leave them switched on at the wall, so they start cooling again as soon as power returns.
- Note the time the power went off. You’ll need it to judge the 4-hour and 24 or 48-hour limits, and it helps with any insurance claim.
- If it’s cold outside (below 8°C), you can move chilled food outdoors in a sealed box, kept dry, out of direct sunlight and away from animals.
Our guide to how long power cuts last explains what the operator’s restoration estimates mean and why they sometimes change.
Eat in the right order
To cut waste, the FSA and FSS suggest eating food in this order during a power cut:
- food from the fridge that needs to be kept chilled
- frozen food that has defrosted and doesn’t need cooking
- perishable food kept at room temperature, such as bread
- tins, jars, bottles and dried food
If you have chilled food that is still safe but you can’t eat it in time, the FSA says it could be shared with neighbours, as long as it has been stored correctly. Someone with power on the next street might be glad of it.
What to throw away
If your fridge has been at 8°C or above for more than 4 hours, the FSA says chilled foods should be thrown away. That includes:
- raw and cooked meat, poultry and fish
- milk, cream, yoghurt and soft cheese
- anything with a use-by date
- anything labelled “keep refrigerated”
- cooked leftovers, cooked rice and pasta
- ready meals, sandwiches, salads and desserts made to be kept chilled
Don’t rely on smell or appearance: food can look and smell fine and still make you ill. When in doubt, throw it out.
Safety: Some people are at higher risk from food poisoning: young children, pregnant women, older people and anyone with an underlying health condition. The FSA advises extra care for them, especially with deli meats and smoked fish, and making sure any food you cook is steaming hot all the way through.
Before you bin anything, take photos and write a list of what you’re throwing away. If you have home insurance, our guide to claiming for food lost in a power cut explains what policies usually cover and what evidence helps.
Your freezer: thawing and refreezing
A freezer holds its temperature much longer than a fridge, especially when it’s full, because frozen food helps keep everything else cold. If the power comes back within the 24 to 48-hour window and food is still frozen solid, it should be fine.
It gets trickier when food has started to thaw. The FSA’s general guidance on freezing and defrosting says:
- once food has fully defrosted, use it within 24 hours
- you can freeze food again once it has been cooked, but you should only reheat it once after that
- keep defrosted raw meat and fish away from ready-to-eat food to avoid cross-contamination
So if your freezer has thawed and you have, say, defrosted mince, you can cook it into a bolognese and freeze that in portions, then reheat each portion once. The FSA doesn’t give separate household guidance for food that has only partly thawed during a power cut, so if you’re unsure whether something stayed frozen, the safest choice is to cook it soon or throw it away.
When the power returns, check the freezer before you put anything new in. Our guide on what to check when the power comes back on takes you through the fridge, freezer and everything else.
Baby milk and feeding
Babies are especially vulnerable to food poisoning, so feeding needs a little extra planning.
Formula milk
The NHS says powdered formula should be made with water at 70°C or more, which kills harmful bacteria. That means boiling the kettle and letting it cool for no more than 30 minutes. In a power cut, you may be able to boil water on a gas hob, but only if your cooker’s instructions say it is safe to use (and to light) without electricity. If you can’t boil water at all, the FSA says to use ready-to-use (ready-to-feed) liquid formula instead.
- Keep a few cartons of ready-to-feed formula in the cupboard if your baby is formula-fed. Check the dates every few months.
- The NHS advises making feeds up one at a time, as your baby needs them, and throwing away any formula left in the bottle after a feed.
- Don’t rely on a fridge that has lost power to store made-up feeds.
Expressed breast milk
The NHS says expressed breast milk can be kept in the fridge at 4°C or lower for up to 8 days, or within 3 days if your fridge runs between 5°C and 10°C. Frozen breast milk keeps for up to 6 months at -18°C or lower. The NHS also says to use defrosted breast milk straight away and not to re-freeze it.
If you’re unsure whether stored milk is still safe after a power cut, ask your midwife, health visitor or NHS 111.
For more on caring for little ones in a power cut, see our guide to looking after babies, older relatives and pets.
Medicines that need refrigerating
Some medicines, such as many insulins and some liquid antibiotics and injections, must be kept in the fridge. NHS pharmacists say these need storing between 2°C and 8°C.
An NHS pharmacist’s advice during a long storm-related power cut was that medicines which warm up to room temperature don’t usually become harmful, but they may become less effective, depending on how warm they got and for how long.
- Keep the fridge closed to hold the temperature as long as possible.
- Read the patient information leaflet in the box. Many medicines state how long they can be kept out of the fridge.
- If you’re still unsure, ask your community pharmacist. Out of hours, call NHS 111.
- Don’t stop taking an essential medicine without speaking to a pharmacist or doctor first.
- If you feel unwell, or a medicine you rely on may not be working, call NHS 111, or 999 in an emergency.
If you or someone at home depends on refrigerated medicine or medical equipment, joining the Priority Services Register is free and can mean extra support from your network operator during a power cut. Our guide to the Priority Services Register explains who can join.
Cooking and hygiene without power
Electric and induction cookers won’t work, but a gas cooker may. The FSA says camping stoves, barbecues and bottled gas stoves can be used, but most are made for outdoor use only, so check the manufacturer’s instructions. Never use a barbecue indoors.
- Cooking on a camping stove takes longer. Make sure food is steaming hot all the way through.
- Wash your hands before handling food. If the water supply is also off, the FSA says you can use alcohol-based hand sanitiser on hands and antibacterial sprays or wipes on surfaces and utensils.
- Keep raw and cooked food apart.
A small stock of food that doesn’t need a fridge or cooking makes all of this easier. Our power cut emergency kit guide suggests what to keep in the cupboard.
Frequently asked questions
How long will my fridge stay cold without power?
Up to about 4 hours if you keep the door shut, according to the Food Standards Agency. Food is safe while the fridge stays below 8°C.
How long will food in the freezer last in 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. These are estimates and vary between models.
Can I refreeze food that defrosted in a power cut?
The FSA says you can freeze food again once it has been cooked, and you should then only reheat it once. Fully defrosted food should be used within 24 hours. Don’t re-freeze defrosted breast milk.
Is milk OK after a power cut?
If the fridge stayed below 8°C, or the power was off for less than 4 hours, milk should be fine. If the fridge reached 8°C or above for more than 4 hours, throw it away.
Will my energy company pay for food I’ve had to throw away?
Network operators don’t usually pay for spoiled food directly, though you may get a fixed payment for a long power cut. Some home insurance policies cover food in the freezer, so check your policy.
Your next step: put a fridge thermometer and a few cartons of long-life food on your shopping list, and if a power cut has just started, note the time and keep those doors shut.
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
- NHS u2013 How to make up baby formula
- NHS u2013 Expressing and storing breast milk
- North Cumbria Integrated Care NHS Foundation Trust u2013 Advice for those who take medications that need refrigerating
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 home, food and health: The Priority Services Register Explained · All power cut guides