What are the most energy-efficient dishwashers?

The true cost of your dishwasher, on both your wallet and the planet, will vary wildly depending on if you get an energy-efficient model or one that's wasteful.

Our extensive dishwasher tests include measuring how much energy and water each appliance uses, so we can highlight those that cost less to run while still doing a great job.

If you just want to see the very best on test, head straight to our guide to the best dishwashers 

Best Eco Buy dishwashers

Every year, we put a range of dishwashers through their paces to find the best models. 

Only logged-in Which? members can view our recommendations below. If you’re not yet a member, join Which? to get instant access.

Dishwasher energy running costs explained

When we test and review dishwashers, we calculate the annual energy running costs – as well as how good they are at getting your plates sparkling clean – to make it easy for you to identify the models that are cheapest to run. 

Which? gives each model a star rating of one to five for energy and water use, where five stars is the best and one is the worst. For example, the most expensive full-sized dishwasher to run that we've tested adds around £100 to your annual bills, while the cheapest costs just over £40 to run each year. 

If you want to find out how much your dishwasher costs to run, use our dishwasher running costs tool, which calculates the annual running cost and lifetime cost of nearly 200 dishwashers from key brands, such as AEG, Hotpoint and Miele. Simply type the model into the search bar to find out how much it adds to your bills each year. 

Buying a new dishwasher? Check annual running costs in our dishwasher reviews. 

Is it worth getting an energy efficient dishwasher?

It's definitely worth getting an energy efficient dishwasher, as Dr Steph Kipling, science team manager and dishwashers scientific advisor, explains: 

'It’s easy to think about the upfront cost of a dishwasher as the final price, but as the Which? scientist responsible for calculating annual running costs of around 2,000 products, I know it’s important to look beyond the number on the price tag.

'Our running costs tell you how much the dishwasher will cost to run for a year, based on using the main programme five times per week. Prices vary considerably, with some dishwashers costing around £40 to run each year, while others can set you back nearly £100 annually.

'Fortunately, most dishwashers we test are very energy and water efficient. Slimline models tend to be slightly less efficient in their energy and water use per place setting compared to full-sized models, but because they use a similar amount of energy overall they cost about the same to run.

'If you have space for a full-sized model and run full loads, this is likely to be more efficient than a smaller capacity model. However, if you’re limited on space or number of dishes, a slimline model shouldn’t affect your energy bills.'

Why you can't always trust energy labels

Energy labels are based on a manufacturer nominated program – so always the eco program. But this doesn’t give a good indication of how efficient the machine will be on its auto or normal program.

The ratings run from A to G, with an A rating being the most efficient. Compare these two dishwashers, which each have 14 place settings:

• The main program on the Hotpoint Hydroforce H8I HP42 L would cost around £69.76 to run annually. It gets a C rating.
• The Bosch SMV4HTX00G costs £11.56 less a year, but receives a worse D rating. 

In March 2021, the energy label was changed to remove the A+++, A++ and A+ ratings to reflect modern standards, although it's still only based on the eco program. 

Five dishwasher energy-saving tips

It's often cheaper to use a dishwasher over handwashing, because it washes more dishes in a single cycle, using less energy and water than if you were to wash those dishes by hand. The following tips could help you save even more energy: 

1. Use your dishwasher's eco programs

Run your dishwasher on its energy-saving or eco program. This will take longer than the main program to get your dishes clean, but will use less energy and water. 

Eco programs wash dishes at lower temperatures and with less water, but for longer to still ensure a thorough clean. On average, economy programs use 30% less energy and water compared with the main program.

Read our dishwasher reviews to find out how efficient a dishwasher's eco mode is compared to the main wash. 

2. Load your dishwasher properly

Aim for a full load each time, so that you're not wasting water and energy. Some modern dishwashers have load sensors, which means they sense how full the dishwasher is, and use water and energy accordingly.

Also be careful not to overfill the dishwasher. Make sure water from the spray arms can reach every item, if not some won't get cleaned properly. 

Large items should go at the back and sides of the racks, too. If big plates are at the front, they can stop the water from reaching the detergent dispenser.

Check out guide on how to load your dishwasher for more advice.

3. Check out cheap electricity tariffs

Some electricity tariffs, such as Economy 7, charge less per unit at night than in the daytime to encourage power usage in off-peak times and to smooth out demand on the grid.

If you're on one of these tariffs, using the delayed-start function to run your machine at night will knock some money off your electricity bill.

4. Don't pre-rinse your dishes 

A good dishwasher will blitz through grease and grime, so you shouldn't have to pre-rinse dishes in the sink, which essentially wastes both water and energy. 

In our tests, we bake food, such as spinach and pasta onto the dishes, and sometimes air dry them to give the dishwashers a tough test. Our Best Buys excel, leaving the dishes sparkling, without any hand rinsing needed. 

5. Keep on top of maintenance 

Make sure the dishwasher is running at it's maximum performance by keeping on top of maintenance tasks, such as cleaning the filter each month. The more you maintain your dishwasher, the longer it could last and the cleaner your dishes will emerge.

Read our expert guide on how to clean a dishwasher. 

We can help you save money on your energy bills. Use our independent free switching tool to find the cheapest energy deal.