In-depth testing by Which? has found that dishwashers are, on average, four times more water efficient than washing by hand per place setting.

The most water-efficient full-sized dishwasher uses almost 10 times less water to wash the same amount of dishes as hand washing them.

Plate for plate and glass for glass, full-sized dishwashers are more efficient than their slimline counterparts. This is because you can wash more dishes in them with only a little bit more water used.

However, even if you were to use the most thirsty slimline model available, it would still use half the water that hand washing does.

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