Water saving products: Water efficient dishwashers

Dishwasher water use

Fully load your dishwasher for greater efficiency

Using a dishwasher to wash your dirty plates and cutlery doesn't use as much water as you might think – in fact, using a dishwasher can be a more water-efficient way of doing the dishes than hand washing. 

The amount of water you will save depends on the model of dishwasher you have, which is where our lab tests come in. 

How dishwashers compare on water efficiency

Our lab tests have revealed that water usage between dishwasher models differed greatly, with one full-sized dishwasher using twice the amount of water for a normal program, compared with another full-sized model during its equivalent wash cycle.

We also found that using an eco or energy-saving program does reduce the amount of water used by your dishwasher, so it's worth using. But our tests revealed large differences exist between models, as you can see from the table below.

 Water use on a main programWater use on a energy-save program
Best full-sized dishwasher10 litres7 litres
Worst full-sized dishwasher21 litres17 litres

Compare dishwashers

Which? has tested more than 150 dishwashers, and 49 of those scored four stars or more for water use during a normal program. Find out which dishwashers save water and which models performed the worst for water and energy efficiency in our comprehensive dishwashers review.

Dishwashers vs washing by hand

Washing by hand may be quick and easy for a few dishes, but it won't always save water compared with a fully loaded dishwasher.

Imagine washing up nearly 130 items with just 7 litres of water – that’s what the most water-efficient dishwasher can do.

To beat that, you'd have to wash everything by hand in less than a single bowlful of water, avoid leaving the tap running and dispense with soaking or rinsing items. 

We measure the water use of every dishwasher we test - you can use our dishwasher comparison tool to find a Best Buy with a five-star rating for water use. 

Watch our video on energy-saving dishwashing for our expert tips on reducing your energy bill.

Top water-saving tips for dishwashers

Wipe, don't rinse 

Rinsing plates and other items, either under the tap or by using a dishwasher pre-rinse program, can use a lot of excess water before you even start washing your dishes. 

Save water by wiping your dishes with a damp sponge or cloth before you place them in the dishwasher.

Fully load your dishwasher 

A dishwasher containing just one plate uses exactly the same amount of water as a fully loaded machine, so ensure your dishwasher is at maximum capacity before you switch it on.

Avoid half-load programs 

Be wary of using half-load dishwasher programs to save water. While this type of program will use less water and energy than a normal cycle, the water saving won't equate to half. It's better to wait until your dishwasher is full and then select an eco or water-saving cycle to save water.

Save water with an energy-save program 

Energy-save or eco programs wash your items at a lower temperature and use less water during the cycle. That's better for the environment and helps to cut energy costs, as well as your water bill if you're on a water meter. 

Energy-save programs typically save 3 litres of water per wash, and we found the washing performance was very similar to normal dishwasher cycles.

Water-efficient loading 

Saving water can even come down to the way you load your dishwasher. While you should load it fully, be careful not to overfill it, as this could prevent some items from being cleaned properly. 

Loading large items at the back and sides of the racks will minimise the chances of needing to wash again – if big plates are at the front, this can stop the water reaching the detergent dispenser.

Read the full Which? dishwashers review for the latest Best Buy dishwashers.

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