Back

How defrosting your freezer could help to reduce your energy bills.

CID 9689 BLG defrost freezer
Energy saving tips
Understanding energy

So, you’ve decided on peas and fish fingers for dinner but the mountain of ice in the freezer won’t let you get near them? Don’t worry, we’ve all been there. However, that frost isn't just a nuisance that’s stopping you from chowing down, it’s also silently draining your wallet.

Perhaps it’s time to cancel those evening plans and finally defrost the freezer. This often overlooked chore could help you reduce your energy bills and the overall cost of running a fridge freezer.

We're committed to helping you save energy and live a more sustainable lifestyle, so let’s get into the topic of defrosting the freezer.

Defrosting the freezer: Why it's a must for energy efficiency.

If a thick layer of ice is building up in your freezer, it’s usually a sign that your appliance is struggling. This inefficiency can have a direct impact on your energy use and monthly bills.

The science behind freezer insulation.

Let’s get straight to the point – frost acts as an insulator. It does this by creating a barrier between your freezer’s cooling elements and the food you’re trying to keep frozen. Because of this, your freezer's compressor has to work extra hard for longer to keep a set temperature.

Think of it this way. If you wore a thick woolly jumper to a hot, tropical beach, your body would have to work harder to keep you cool. It’s a similar situation with your freezer, but replace the woolly jumper with a layer of ice. This increased workload equals higher electricity use and, yes, you’ve guessed it, higher energy bills.

How does your freezer's efficiency affect food quality?

What’s more, a freezer struggling with ice build up is less efficient at keeping your food properly frozen. This can cause food to become dry and discoloured and even spoil.

The final point to add is on the subject of space. The build up of ice reduces your usable storage space, leading to food being forgotten at the back of the freezer and ultimately thrown away.

The financial impact of defrosting your freezer.

Here, we’ll look at the numbers and show you just how much a simple defrosting of your freezer could save you.

How much energy does the average fridge freezer use?

On average, an integrated fridge freezer can cost around £77 per year to run, while a freestanding version costs closer to £79. However, one of those large American style fridge freezers can cost around £119 per year to run.1

What could you save from a simple defrost?

Based on current average UK electricity unit rates (26.35p per kWh as of October 2025) a 30% reduction from defrosting could equal £15-30 in annual savings.2 So, there’s even more reason to start preparing for a defrost. Learn more about the average UK energy bill.

Appliance energy ratings: What they mean for your freezer.

Ensuring your fridge freezer is as energy efficient as possible comes down to the Energy Performance Certificate (EPC) rating label. In 2021, the way of doing EPC labels was changed. Now, if an appliance has an A rating, it's working efficiently. However, if the rating is lower, it might be time for a new, energy efficient upgrade.

Here are some comparisons to put everything into perspective:

  • A+++ is now equivalent to a B or C rating.

  • A++ is now equivalent to a D or E rating.

  • A+ is now equivalent to an F or G rating.

Learn more about EPC ratings for appliances.

How often should you defrost your freezer?

So, now (hopefully) you’re ready to roll up your sleeves and get stuck into the freezer, but how often will this need to be done? The general guideline is at least once a year – or whenever the ice build up reaches critical levels!

Warning signs it’s time to defrost:

  • You can see visible ice on the interior walls, shelves, or drawers.

  • It’s getting more and more difficult to close the freezer door properly due to the ice.

  • There’s less storage space inside and it seems to be getting tighter.

  • Your food is getting excess frost even when it’s well packaged.

  • Finally, your freezer is running almost constantly and/or making strange noises.

Your step by step guide to defrosting the freezer.

Ready to get started? Follow our five simple steps for a safe and effective defrosting session.

Preparation makes perfect.

Use up all the food in your freezer before you get stuck in – perhaps before the ‘big shop’. Alternatively, perhaps a friendly neighbour can let you store the remaining food in their freezer until you’re done.

Next, gather your tools, including:

  • Absorbent paper towels.

  • Old cloth.

  • Shallow bowls.

  • Plastic ice scraper (avoid metal scrapers).

Don’t ignore the safety measures!

  • ALWAYS switch off and unplug your freezer at the mains before you begin, preventing potential electric shocks and damage to the appliance.
  • ALWAYS keep pets and small children away from the area for their own safety.
  • NEVER use sharp or metal objects like knives, screwdrivers, or chisels to chip away the ice. Not only could you damage the freezer and potentially release refrigerants, but it could also be costly to repair.
  • NEVER using boiling water directly on interior plastic surfaces. The extreme temperature change could cause cracking or warping.

Follow an effective defrosting method.

Switch off and unplug the freezer and leave the door open, then let the ice melt naturally. This is the safest method but also, the slowest (think, overnight). Remember to regularly replace towels and empty water bowls.

Only speed up with caution.

If you do want to speed up the process, place bowls of hot (not boiling) water inside the freezer, closing the door for 10-15 minutes at a time. This safe method lets the steam loosen the ice. Repeat as needed, carefully removing and reheating the bowls.

Getting your freezer back into action.

Once all ice has melted, wipe down the interior thoroughly with a mild detergent solution. Rinse with clean water but make sure it dries completely, preventing re-frosting and mould growth.

Next, check the door seals for signs of damage, cracks, or dirt that could prevent a tight seal. Clean the doors with warm, soapy water in case anything is obstructing them.

Finally, plug your freezer back into the mains. However, don’t start using it straight away, let it cool down to its optimal temperature first (around -18°C).

Tips on preventing future ice build up in your freezer.

Once your freezer is defrosted, clean, and back to its rightful temperature, follow these tips to prevent future freezer frost.

Check the door seals.

A simple test is shutting the door on a piece of paper. Can you pull the paper out easily? If so, the seal might need replacing because exposure to warm air creates frost.

Be wary of leaving the door open.

This is a simple one. Reduce how long and often you open the freezer door. Each time it’s open, warm, moist air enters, eventually equalling, yep, frost!

Let your food cool down first.

Meal prepping for the week? Always wait for the food to cool completely before putting it in the freezer because hot steam turns to ice.

Choose proper packaging.

Make sure any food you keep in the freezer is tightly wrapped or sealed in an airtight container. These methods stop moisture from escaping and forming more ice.

Don’t over fill the freezer.

Overpacking your freezer with food could prevent the air from circulating. Plus, it could obstruct the door seal.

The big question: Combined fridge freezer or separate?

A combined fridge freezer is usually more energy efficient and cheaper to run than two separate units. This is because of the shared insulation and single compressor.

However, there are some modern separate units that are highly efficient, giving combined models a run for their money. Another benefit is storage space – separate units often give you more of it.

Ready to start making a difference?

Don't let frost build up drain your energy budget, take action today! A defrosted freezer means more storage space, better efficiency, and a happier wallet.

Explore our energy saving tips.

Keen to find out about other energy draining appliances? We’ve done similar deep dives into the television and washing machine.

There are lots of little tricks you can do to save energy. From turning down your thermostat to draught proofing your home, explore more energy saving tips to help hone your energy use.

Published 05/11/2025