Energy-efficient washing machines

Washing machine running costs vary enormously, from lower than £26 – the cheapest we've tested – to almost £100. 

Energy bills are high at the moment, but choosing efficient appliances can help keep costs to a minimum. Our washing machine reviews reveal the best and worst we've tested and how much each one costs to run.

Just want to see the very best on test? Head straight to our guide to the best washing machines. 

Top five energy-efficient washing machines

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How much does a washing machine cost to use?

A washing machine can cost anything from less than £26 a year to almost £100, under the energy price cap that comes into effect in April 2025. 

It depends on many factors, including machine capacity, how much you use your washing machine, the amount of clothes you put in and the programs you choose. 

For example, our data shows that a 7kg-capacity model costs on average about £56 a year to run, while a 14kg-capacity model costs £86 a year on average.  

But choosing an efficient model makes an enormous difference too. You can use our energy running cost tool to see which washing machines are the most economical to run at the moment.

Our energy calculations are based on each washing machine being used four times a week to wash an 80% full load of cottons, because that's the wash people most commonly use.

We've calculated running costs for all the major appliances in your home, so you can get a handle on how much electricity you're using and where. 

Find out more in our guide to how much your appliances cost to run.

What is the most energy-efficient type of washing machine?

There isn't really a 'type' of washing machines that's more efficient than others, but a larger capacity washing machine is probably going to use more energy per wash than one that can fit in fewer items. 

However, choosing a machine that can wash more at once means you'll need to run it less frequently, which goes some way to balancing out the cost per wash.

For example, if you wash an average of 35kg of clothing in a week, that's five loads in a 7kg machine, but only three full loads in a 12kg machine – and we've tested models that can hold up to 14kg at once. For reference, 1kg of clothing is equal to approximately one full outfit or two towels. 

The most energy-efficient washing machines we test receive our Eco Buy badge, which you can read more about below.

What is a Which? Eco Buy?

Usually, the more energy a washing machine uses, the better it is at cleaning. So it’s really hard to find one that has a good balance of both.

That's why we’ve started highlighting the rare models that can achieve both as Eco Buys. 

A washing machine has to be efficient with both energy and water – and also, crucially, clean well – to get our Eco Buy recommendation. 

This makes it easier for you to know which will be kinder to the planet and your bills.

To see our pick of Eco Buys, see all our washing machine reviews.

What does the energy label mean on a washing machine?

The energy label you see in the shop or online will give you an indication of where the washing machine sits in terms of energy use, but it doesn’t give you the full picture.

The label ratings changed in March 2021 to get rid of all the pluses (no more A+++, A++ or A+). It now starts at G (for the least efficient) and goes up to A (for the most efficient). But what does that actually mean for your wallet and the planet? It should mean that appliances get more efficient, as brands fight for the top A rating. But we've found that two washing machines with the same energy label rating can vary a lot. 

Our reviews go one step further and show how much each machine will actually cost to run. Unlike the energy label, which is largely based around washing clothes at 60°C, we base our energy running costs solely on the 40°C cottons wash, because that’s what people most commonly use. This means that our energy ratings are more accurate than the official ones.

Washing machine energy-saving tips

• Wash at lower temperatures Our research has found that making the shift from 40°C to 30°C cuts energy costs by 38%, and going from 40°C to 20°C cuts costs by 62%. Unless you’re washing really soiled clothes, modern machines (particularly Best Buys) will still do a good job most of the time. See our washing machine temperature guide for more information.
• Switch to a liquid detergent It will wash better at lower temperatures than powder detergents. We've rounded up the best options in our best laundry detergents guide.
• Wash less often It sounds obvious, but buying a machine with the right capacity for your needs will mean you can wash less often, as you’ll get more done in one go. If you don’t have enough laundry to fill the drum, go for a quick program, which will often have a lower recommended-fill level.
• Stop overwashing your clothes Not only is this a waste, but it could be causing fading, shrinkage and mis-shaping. Chip Bergh, the chief executive of denim brand Levi's, famously said that you never need to wash its jeans, but we advise you to wash jeans every six to 10 wears.

From washing delicates to jeans and sportswear, we've got the answer to your laundry questions. Read our expert guide on how to wash clothes, towels and bedding.