Water saving products Water efficient washing machines

Energy-efficient washing machines

Washing a full load in your machine saves energy

Improving your washing machine's water efficiency is a good way of cutting unnecessary water wastage in your home – and reducing your water usage if you're on a water meter will save you money too.

Just as washing machines have become more energy efficient in recent years, improvements have also been made to washing machine water efficiency.

It is now possible to choose a washing machine model that uses less water but still gets your clothes clean.

Water and washing machines

Some washing machines, however, are better than others at saving water.

The average washing machine uses 9.3 litres of water for every kilogram of cotton clothes it washes. But during our washing machine testing, we found water usage varied between models, ranging from one that used just 6.0 litres of water to another that consumed 12.6 litres of water per kilogram.

To put those figures into perspective, if you did two 40oC cotton washes a week for a year with the efficient machine instead of the inefficient one, you'd use 2,912 litres less water – that’s more than 37 baths full of water. The table below shows the best and worst washing machines we have tested in terms of water usage for a 5kg cotton load. 

How different washing machines compare
 Litres of water
Best31 litres
Worst60 litres

Table notes

Best and worst performers for water usage
Test based on washing a maximum 5kg load in a 40C cotton wash

Read the full Which? washing machines review.

Compare washing machines

Which? has tested more than 200 washing machines, and each one is scored on how much water it uses during a normal washing cycle. Find out which washing machines were awarded coveted Which? Best Buy status in our comprehensive washing machines review. In our 'Compare features and prices' tool in the review, you can select models that are particularly efficient in their water use.

Washing machine cycles and water

Different cycles also use varying amounts of water. We sampled 234 washing machines with different drum capacities and found the average 40oC cotton wash used 62.8 litres of water per wash – 15 litres more than a 40oC synthetic wash, which used just 47.8 litres.

But the maximum wash load for a synthetic wash is usually about half of the amount that you can launder on the cotton program. This means that, per kilogram of washing you can launder in one go, cotton washes usually work out better – but only if you always fill the drum. Synthetic loads use more water per kilogram of load in order to avoid creasing. 

Washing a cotton load that’s only around 70% full wastes, on average, 3.8 litres per wash.

Top water saving tips for washing machines

There are also some simple ways you can improve your washing machine's water efficiency, whatever model you have at home.

Wash full loads 

40oC cotton washes are designed to take a full drum of laundry, so always try to wash the maximum amount in each load to get the most value from the water and energy you're using. 

If you find you're not able to fill the drum of your 8kg washing machine on a regular basis, it might be worth considering a washing machine with a smaller drum size.

Avoid using extra rinse 

If you have very sensitive skin you may find it necessary to use the extra-rinse function on your washing machine to remove more detergent from laundered clothes. But try not to use this function unless you really need to, as it's another water waster.

Read the full Which? washing machines review.

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Last updated: 19 August 2011

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