What to Do With Freezer Food After a Power Cut (UK): How Long It Lasts and When to Throw It Away

A power cut is often a bigger worry for what’s in the freezer than for the lights. A full chest freezer can hold hundreds of pounds of food, and nobody wants to bin it unnecessarily, or eat something that’s unsafe. With the government’s Be Ready campaign, launched on 22 October 2026, asking households to plan for 3 days of disruption, here’s what UK food safety guidance says about keeping, cooking and throwing away freezer food, plus how to claim for what you lose.

How long will food stay frozen?

The FSA says these are estimates. Others are more cautious: Beko says food “will remain frozen for around 12 hours if left in the freezer”, and National Grid’s power cut leaflet says contents could stay frozen “for up to 12 hours”, depending on the type of freezer. So treat 48 hours as the best case for a full, well-sealed freezer.

The good news is that most power cuts are short. The FSA says: “If the power outage is for less than 4 hours this is unlikely to impact the safety of food in chilled or frozen storage.”

What to do during the power cut

1. Keep the doors shut. The FSA says to keep fridge and freezer doors “closed as much as possible”. Every time you open them, cold air escapes.
2. Don’t move food into cool bags. Beko says to “resist the temptation to remove food and use cool bags”. A closed freezer stays colder for longer.
3. Huddle the food together. If your freezer isn’t full, NIE Networks suggests grouping packs into an “igloo” so they protect each other, and putting packs on a tray so that if they thaw, their juices won’t drip onto other food.
4. Add ice blocks if you have them. Bosch says ice blocks “can be used to slow down the thawing process”.
5. Eat the fridge food first. The FSA’s order is: food that needs refrigeration, then defrosted frozen food that doesn’t need cooking, then room-temperature perishable food, then tins, jars and dried food.
6. Use the cold outside. The FSA says that if it’s below 8°C outside, you can store food outdoors “out of direct sunlight”, in “a sealed box to prevent contamination and tampering”, and protected from animals.

The fridge: the 8°C and 4-hour rule

The FSA recommends keeping your fridge at 5°C or below, but says that in a power cut, chilled food can be stored at temperatures under 8°C. Once the fridge reaches 8°C or above, eat chilled food such as meat, fish, ready meals and leftovers within 4 hours. After that, the FSA says to throw it away, unless the power comes back within the 4 hours. A fridge thermometer tells you when it’s too warm.

When the power comes back: keep, cook or throw away

This draws on FSA guidance:

• Defrosted food: the FSA says “it’s also important to use food within 24 hours after it’s been fully defrosted”. That advice is about defrosting in the fridge, so it assumes the food has stayed cold.
• Refreezing: freezing doesn’t kill bacteria. The FSA says “the bacteria haven’t been killed, and they may be revived as the food defrosts”. But it also says “you can freeze food again once cooked, but you’ll only be able to reheat it once after that”. So cook defrosted raw meat before refreezing it.
• Food still frozen: FSA guidance for food businesses treats food that’s still “hard and icy” as frozen, and says to move it to another freezer straight away if yours isn’t working.
• Ice cream: FSA guidance says food that has to be kept frozen, such as ice cream, “cannot be re-frozen once it has started to defrost”.
• Fruit and veg: the UK Chief Medical Officers’ power cut advice says “defrosted frozen fruit and vegetables will last a couple of days”.

If food is partly defrosted and you’re unsure, treat it as defrosted. The FSA warns that “partially defrosted food may not cook evenly”, so make sure it’s cooked through and steaming hot.

Check your freezer’s temperature

The FSA says your freezer “should be around -18°C” and your fridge “between 0 and 5°C”, and recommends checking with a thermometer once a week. A max/min thermometer is even more useful after a power cut, as it shows how warm the freezer got while you weren’t looking.

Can you claim for spoilt food?

Your electricity network won’t pay for food

UK Power Networks says it’s “not liable for any loss of fridge freezer contents”, and NIE Networks says it is “unable to pay to cover freezer contents”. Both point you to your home insurance instead.

But you may get an automatic payment

In England, Scotland and Wales, under Ofgem’s Guaranteed Standards for 2026, you can get £100 if you’re a household and your power is off for more than 12 hours (when fewer than 5,000 properties are affected) or more than 24 hours (when 5,000 or more are affected). You get £45 more for each extra 12 hours, up to £400 for larger power cuts. Ofgem says you “will automatically be paid by your local network operator”. Northern Ireland has different rules. NIE Networks says you may be due compensation if your power was off for more than 24 hours for reasons other than severe weather.

In severe weather, the rules change. For the less severe storm category, you get £90 after 24 hours, and £45 for every 6 hours after that. For the more severe category, it’s £90 after 48 hours, then £45 for every 6 hours after that. The maximum is £2,235. Ofgem says these payments don’t apply to “blackouts caused by a national power shortage”.

Check your home contents insurance

The Association of British Insurers says “some home contents policies may cover loss of food in freezers (up to the policy limit) due to failure in the power supply”. Limits and exclusions vary:

Ageas says it won’t cover damage caused by your supplier cutting off your power, for example over unpaid bills. Before claiming, check your excess, as it may be more than the food is worth. Take photos and make a list of what you’ve thrown away.

The kit worth buying

Frequently asked questions

Sources

• Food Standards Agency (GOV.UK) — Food safety in a power cut and How to chill, freeze and defrost food safely; FSA — Safer Food Better Business: Freezing (PDF)
• GOV.UK — UK CMOs: food and nutrition advice during a national power outage; GOV.UK Be Ready — Power cuts
• NIE Networks — How do I keep food safe? and Can I claim for food?
• Bosch — How long will food last in a freezer without power?; Beko — Fridge freezer lost power in a power cut; National Grid — Power cut leaflet
• N.C. Cooperative Extension — Coin in the cup: risky
• Ofgem — Check if you can get a payment for a power cut; UK Power Networks — A power cut ruined food in my fridge freezer
• ABI — Insurance cover for disruption to power supplies
• Admiral — Freezer cover; AA — Power cuts; Lloyds Bank — Home insurance policy limits (PDF); Dial Direct — Freezer contents cover; Ageas — Why a freezer food claim may not be covered
• NHS — Storing and travelling with rapid-acting insulin
• ETI — Digital fridge/freezer alarm thermometer; Brannan — Dial fridge/freezer thermometer (PDF); Charlies — Campingaz Freez’Pack M30; Coleman — 52QT Xtreme cooler box

Related reading: can you keep a freezer in a garage?, how to keep insulin cold in a power cut, what size power bank you need for a power cut and emergency kit items that expire.