How long will my fridge and freezer stay cold in a power cut? A UK food-safety guide

The FSA says a cut of under 4 hours is unlikely to affect the safety of chilled or frozen food. So in a short cut, the only thing really at risk is the last choc ice, and only because someone will decide it needs rescuing.

The numbers at a glance

The FSA notes these times vary with your appliance’s make and model and the room temperature. Opening the doors often warms them faster.

Before a power cut

What temperature should my fridge be?

The FSA says a fridge should run between 0 and 5°C and a freezer at around -18°C. It recommends a fridge thermometer, checked once a week. In a power cut, that same thermometer is what tells you whether your food is still safe. Without one, you’re guessing.

• Keep the freezer well packed. By the FSA figures, a full freezer keeps food frozen about twice as long as a half-full one. Fill gaps with plastic bottles of tap water, leaving room at the top for the ice to expand. In a power cut they become ice packs.
• Keep food that needs no fridge and no cooking. The public GOV.UK Prepare site suggests tins of meat, fruit or veg that you can eat straight from the can, a tin opener, and baby formula (ready-made) and pet food if you need them.
• Write 105 on paper, not just in your phone, as Prepare advises.

The first 10 minutes

Should I open the fridge during a power cut?

Only when you must. Each opening lets warm air in and shortens the time your food stays safe. The FSA and Prepare both say keep fridge and freezer doors closed. When you do open the fridge, take out everything for the next meal in one go.

1. Report it. Use your network operator’s website (find it via powercut105.com) or call 105 free. In Northern Ireland, call 03457 643643.
2. Note the time the power went off. The 4-hour and 48-hour figures count from here.
3. Read the fridge thermometer quickly, then shut the door. Ask everyone at home to keep both doors closed.
4. Unplug your TV and computer, which Prepare warns a surge can damage when power returns.

If it lasts longer than 4 hours

Is food in the fridge still safe after 4 hours without power?

It depends on the temperature, not just the clock. The FSA says chilled food can stay in the fridge during a power cut while it’s under 8°C. Once the fridge reaches 8°C or more, eat that food within 4 hours. After that, throw it away, unless the power came back within 4 hours.

No thermometer? Our advice: once the FSA’s 4-hour fridge figure has passed, stop assuming it’s cold.

Which food should I eat first?

Eat the fridge food first, then defrosted frozen food that doesn’t need cooking, then perishables kept at room temperature, such as bread. Save tins, jars and dried food for last. That’s the order the FSA and Food Standards Scotland recommend.

Got more than you can eat? The FSA says you could share properly stored chilled food with neighbours.

Can I keep food outside if it’s cold?

Yes, if it’s below 8°C outside. The FSA says to use a sealed box, somewhere clean and dry, out of direct sun and away from animals. Food Standards Scotland points out that sun and shade can differ, so choose the spot with care.

Does a cool box help? (What we’d add)

Yes, for a few essentials. Move the chilled things you’ll reach for most into a cool box with ice packs or your frozen water bottles, so the main fridge stays shut for longer. Keep insulin and other medicines off the ice packs (see the extra help box below).

How do I cook safely without power?

Electric and induction hobs won’t work, but a gas hob may. The FSA says most camping stoves and barbecues are designed for outdoor use only, and Food Standards Scotland says never use a barbecue indoors. Cook food until it’s steaming hot all the way through.

If the water is off too, the FSA says hand sanitiser and antibacterial wipes can stand in for washing.

Keep, use soon or throw away: food by food

Check the fridge temperature first, then use these tables.

Fridge food

Sources: FSA, Food Standards Scotland.

Freezer food

If in doubt, throw it out. If you don’t know how warm something got, or for how long, don’t eat it. Take extra care when cooking for anyone the FSA lists as at higher risk of food poisoning: young children, pregnant women, older people, and anyone with an underlying health condition.

Refreezing: what’s allowed

Can I refreeze food that thawed in a power cut?

Not if it’s raw. NHS inform says raw meat, fish and poultry can’t be refrozen once defrosted, and thawed ice cream and frozen desserts shouldn’t go back either. Cook defrosted raw food within 24 hours instead. Once it’s cooked and cooled you can freeze it, and the FSA says you can then reheat it only once.

Food still frozen solid can stay put. The UK guidance we checked has no rule for partly thawed food, so our advice is to treat it as defrosted.

When the power comes back

What should I check when the power comes back on?

Read the fridge thermometer first, and work out how long the power was off. Sort the fridge using the 8°C rule. Then go through the freezer item by item: anything still frozen solid stays, and anything defrosted follows the refreezing rules above.

• Clean up. The FSA says to wash surfaces, utensils and hands in warm soapy water after contact with raw or thawing meat.
• Let the fridge settle (our advice). Wait until it’s back between 0 and 5°C before restocking.

Will I get compensation for spoiled food?

Payments aren’t worked out from the food you lost. In England, Scotland and Wales, Ofgem’s rules mean your network operator pays a fixed amount if your power is off too long: automatically if it has your bank details, otherwise contact it. For a home, that’s £100 when fewer than 5,000 properties are off for over 12 hours, plus £45 for each further 12 hours.

You don’t need to claim. The limit is 24 hours when more than 5,000 properties are affected, and severe storms have their own rules. For a large food loss, check your home contents insurance for fridge or freezer cover.

If you live in Northern Ireland, Scotland or Wales

• Northern Ireland: report a power cut on 03457 643643. NIE Networks has a guaranteed standard to restore power within 24 hours. If it misses it, homes are due £50, then £25 for each further 12 hours. You must claim within 1 month, and severe weather can be exempt. The FSA advice here applies in Northern Ireland.
• Scotland: call 105. Food Standards Scotland gives the same 4-hour, 48-hour and 8°C figures. Ofgem’s payment rules apply.
• Wales: call 105. The FSA advice applies and is available in Welsh. Ofgem’s payment rules apply.

People who need extra help

• Insulin and other fridge medicines. The NHS says keep insulin away from the freezer section and throw it away if it freezes. Insulin that gets too warm may not work properly. In a cool bag, keep it away from ice packs. A pen already in use can stay at room temperature for a limited time: up to 4 weeks for rapid-acting insulin, and by brand for long-acting. Unsure whether a medicine is still safe? Ask your pharmacist, doctor or diabetes nurse before using it.
• Priority Services Register. This free service gives advance notice of planned power cuts wherever possible, and priority support in an emergency, says Prepare. Diabetes UK says everyone living with diabetes is eligible. Sign up at thepsr.co.uk (England and Wales), psrscotland.com (Scotland) or through a Customer Care Register (Northern Ireland).
• Medical equipment. Prepare advises making a plan now with your care provider or clinical team.
• Babies. You need boiled water to make up formula safely. If you can’t boil water, the FSA suggests ready-to-use formula. See the NHS guide to making up formula.
• Neighbours. Check in on vulnerable neighbours and, if you can, offer to share food, as Prepare suggests.

Useful to have, grouped by need

Knowing whether food is safe – Fridge thermometer: the only way to use the FSA’s 8°C rule. – Freezer thermometer: shows whether it’s still holding near -18°C.

Keeping things cold for longer – Cool box and ice packs: essentials stay close, so the fridge stays shut.

Eating without a fridge or hob – Ready-to-eat tins and a manual tin opener: on the Prepare list, no cooking needed. – A torch: safer than candles, says Prepare, and you’ll need it to read the thermometer.

We’re putting together an Essentials Kit: the non-food essentials from the Prepare list in one bag, with a card saying exactly which water and tins to add. Join the list to hear when it’s ready.

Ready, not worried: a thermometer, a full freezer and a closed door do most of the work.

Sources

• Food Standards Agency, Food safety in a power cut: advice for consumers (Welsh version)
• Food Standards Agency, How to chill, freeze and defrost food safely
• GOV.UK, Best before and use-by dates
• Food Standards Scotland, Food safety during a power cut
• NHS inform, Preparing and cooking food safely
• GOV.UK Prepare, Power cuts
• powercut105.com (linked from GOV.UK Prepare)
• Ofgem, Check if you can get a payment for a power cut
• NIE Networks, Customer standards
• NHS, Storing rapid-acting insulin and long-acting insulin
• NHS, Making up baby formula
• Diabetes UK, Priority Services Register
• Priority Services Register: thepsr.co.uk, psrscotland.com, nidirect Customer Care Registers