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How to defrost your freezer

By Ben Slater

Learn how to defrost your freezer quickly, without making a mess of your kitchen and wasting food.

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Having to manually defrost a freezer is a household chore most people could live without. It can be a messy and time-consuming job, so we've put together 10 simple steps to help make this dreaded job as painless as possible.

Thankfully, most new freezers and fridge freezers come with a frost-free feature, so they don’t ever need to be manually defrosted. But if you still have an older-style freezer that ices up and needs to be defrosted, follow our steps below to defrost it quickly, without ending up with water all over your floor, or losing any frozen food.

Or, read our fridge freezer and freezer reviews to buy yourself a new frost-free model and save yourself the effort.

How to defrost a freezer quickly

The safest way to defrost your freezer (for both you and your freezer) is to let it defrost on its own once you’ve turned it off. If you search for ‘defrosting a freezer’ online you’ll see all sorts of wacky suggestions for how you can speed the process up. But these methods aren't always safe and many don’t really work. They could also damage or break your freezer and invalidate your warranty.

To defrost a freezer quickly, follow these 10 simple steps:

1. Switch your freezer off.

2. Prepare your space. Put old newspaper around the freezer to stop any water from reaching the floor as the ice melts. Then put dry towels down inside your freezer to soak up any water as it defrosts. Remember to wring these out every so often or replace them with dry towels

3. Remove all the frozen food straightaway. To prevent items from thawing, place them in a cool bag or insulated cooler box with ice packs. Store this in the coldest area of your house, away from direct sunlight. If you don’t have a cool box, see whether an obliging neighbour can temporarily store some or all of your frozen food.

4. Remove all drawers, shelves and bottle holders – anything that can be removed – and set them aside for cleaning. Don’t try and force them out if they're stuck because of the ice. You'll be able to remove them later as the ice melts.

5. If your freezer has a drainage hose or a tray underneath it, make sure you’re set up to dispose of the water in these as the ice melts.

6. Wait for the ice to melt. You've probably seen some of the following methods to speed this process up: using a hairdryer, wallpaper strippers, a heat gun, a steam cleaner, defrosting with car de-icer, defrosting with salt and even hacking at the ice with a knife. But there are numerous reasons why you shouldn’t try these. Mixing electricity and water, using de-icer in a place you keep your food, or risking damage to your freezer (or yourself) by hacking at the ice with a sharp knife are not recommended. Special freezer defroster sprays are also available but reviews for these are mixed, and bear in mind that anything that’s not recommended by your manufacturer could invalidate your warranty.

7. Take this opportunity to clean your freezer, getting into all those nooks and crannies where bits of dirt have collected.

8. Dry the freezer as much as possible, by wiping with dry towels, before you switch it back on. This will help keep ice from immediately building back up.

9. Once you’ve switched the freezer back on, give it time to cool down again before putting your frozen food back in. This can take several hours.

10. Any food that has started to defrost shouldn’t be refrozen.

Why should you defrost a freezer?

For the simple reason that you’ve got a build-up of ice that’s taking up space where your food should be. If you leave it long enough, enough ice can build up to prevent the door from closing properly, so you're better off defrosting the freezer before it gets to this stage.

As well as this ice squatting in space where your food should be, the ice (although cold) actually acts as an insulator. This means your freezer has to run longer and work harder in order to penetrate that block of ice to keep your food cold. This means it will cost you more in electricity to run.

Frost build-up can be caused by leaving the freezer door open, or because there's a problem with your freezer seal. If you notice more frost building up than usual, and you know you’re closing the freezer door as soon as you’ve popped food in or taken it out, it’s worth checking your freezer seal.

If your freezer seal is on its way out, it might be time to buy a new freezer. Check our freezer Best Buys for those we rank top in our reviews.

How often should you defrost a freezer?

The simple answer is as soon as ice build-up becomes noticeable.

How to defrost a freezer without turning it off

You should always turn the freezer off if you’re going to defrost it – otherwise the ice won’t melt and you’ll have to attempt hacking it off (see why that’s not a good idea in our steps above). If you don’t have cool boxes to store your frozen food and there are no kind neighbours on hand, use ice build up as an opportunity to defrost and eat all those bags and boxes that have been hiding in your freezer for the past few months.

How to defrost a freezer compartment in a fridge

If you need to defrost a freezer compartment inside a fridge and they don’t have separate controls, you’ll need to remove the food from the fridge as well. If your fridge has a separate door and different controls from your freezer, then it’s safe to leave food in your fridge.

How to defrost a freezer without losing food

If you’re going to defrost a freezer you need to remove the food. Previously frozen food that's been defrosted should not be frozen again as there’s a higher chance of food poisoning when you finally come to eat it. The exception is for food that’s been previously frozen, defrosted and cooked. This can be frozen again without a higher chance of food poisoning. So, if your frozen food defrosts while you’re defrosting the freezer, you’re either going to have to cook it before you re-freeze it, or eat it almost straightaway. The Food Standards Agency advises that defrosted food can be stored in the fridge for up to two days before it needs to be cooked or thrown away.

If you want to keep your food frozen while you defrost your freezer, you may have to invest in cool boxes or cool bags, freeze the ice packs that go in them and then pop your frozen food in there. Keep these out of direct sunlight. The alternative is to ask someone close by to look after your frozen food in their freezer until you’ve finished defrosting.

Why you need to defrost a freezer before moving home

With everything you need to think about when you’re moving home, it can be easy to forget that you need to defrost your freezer in advance. Otherwise you’ll have to deal with ice and melting water on the day of the move, which is not what you need.

Even if you have a frost-free freezer, you should make sure it is fully dry and aired before your move, otherwise you could end up with a musty smell inside.

Never leave food in your freezer and expect the movers to move it full. Freezers aren’t designed to be lifted full of food and you could damage it. When you're packing it up, make sure you remove all the shelves and trays – and any other removable parts – and pack them, otherwise they could break in the move.

Manual defrost freezer vs frost free

You could save yourself all the effort of defrosting your freezer by simply buying a frost-free fridge freezer. Chest freezers aren't frost-free, but almost half of the freestanding and built-in freezers we've tested since July 2015 are. That percentage is even higher for fridge freezers, with nearly 90% of the models we've tested since July having frost-free freezers. Frost-free is now so common that there are plenty of affordable options out there, so there's no reason to ever defrost your freezer by hand again.

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