Dishwashers buying guide

A dishwasher saves you the time and drudgery of washing up and helps to keep your kitchen tidy - simply pop your dirty dishes into the machine out of sight. In terms of cleanliness and energy efficiency, a dishwasher is more effective than hand washing can ever be. We can even connect it up for you and remove an old machine. Follow our points to consider to help you make the right choice.

View our range of dishwashers. Watch our John Lewis dishwasher video.

Choose the right size of dishwasher

The guide to capacity is the number of place settings, i.e. the maximum number of plates and eating utensils the machine can wash (excluding any serving dishes, saucepans or utensils). A typical 12 place setting capacity would include:

  • 12 x 24cm dinner plates
  • 12 x 23cm soup plates
  • 12 x 18.5cm dessert plates
  • 12 tea cups and saucers
  • 12 tumblers
  • 12 knives, forks, soup spoons, teaspoons and dessertspoons

If a full-sized dishwasher seems too big, then your other options are a slimline model, which is usually around 45cm wide and takes around 9 place settings, but the same height and depth.

Note: even if there's only one or two of you, if you like to use lots of pots and pans, consider getting a full-sized machine.

compact model is ideal if you have very limited space and if a dishwashing load of around 4 place settings will adequately meet your needs.

There are also integrated models which can be completely concealed behind a matching fascia for a uniform look to your kitchen. Semi-integrated models are partially concealed, with the machine’s control panel visible and readily accessible.

Full size and slimline models are designed to fit under a standard worktop. Some dishwashers have a removable worktop which may save you around 3cm if it's going to be a tight fit.

Dishwasher programmes

Programmes will vary slightly depending on the machine, but there will usually be at least three and often a rinse only cycle. The main wash programme with generally be at 65ºC, particularly useful if there are saucepans included in the load; usually there'll be an economy programme for normal washes, and a light or delicates programme.

Top of the range machines sometimes offer a glasses programme too, or a half load option where you only need to use one of the two levels in the machine.

Some machines will offer a rinse and hold function for very heavy soiling. A rinse only setting can be useful - just select if you don't have a full load and don't want food debris to create odour or harden on plates and utensils.

Most machines have particular sensor features designed to adapt the programme to the load in the machine, e.g. by assessing how soiled the load is and reducing or increasing the amount of water or rinses needed.

There are several ways in which dishes are dried in the machine; simple residual heat (heat created from the washing process), heated air or some kind of fan assistance. The 
latter are the quickest methods and serve to save energy because of their speed.

full-sized dishwashers
View our range of slimline dishwashers
compact dishwashers
alt text here

Spray arm technology

Detergent, dish placement and heat are all important cleaning elements in getting your dishes clean, but how the water is sprayed around the inside the dishwasher is important too - you don't want any blind spots where food debris might remain clinging to your crockery.

Traditional spray arms

Traditional spray arms distribute water in a circular pattern. Water in the basin of the dishwasher is pumped into 2 spray arms - one under the lower basket, one under the upper – and propelled to the water jets, where it’s forced out and sprayed against the dirty dishes. The force of the water also makes the arms that hold the spray jets rotate, just like a lawn sprinkler.

Additional spray arm

Certain manufacturers champion a third, smaller spray arm that is attached to the roof of the dishwasher. This also spins while in action, showering the upper basket, and is particularly useful if the dishwasher features a dedicated cutlery tray positioned at the top of the tub. Miele has the largest range of dishwashers with this feature.

Satellite spray arm

Packing your dishwasher with irregularly-shaped items usually means a drop in cleaning quality. A satellite spray arm is a mini spray arm on the end of the lower spray arm.

As the smaller and parent spray arms spin, the special double-rotation creates a powerful spiral of water that cleans perfectly in the corners that other washers can’t reach. AEG, Electrolux and Smeg are big fans of this design.

WaterWall™ Jet washing system

Invented by Samsung, the lower spray arm is substituted by a bar that moves from back to front along the bottom of the tub. This gives you maximum coverage with consistent high-pressure water jets, and a wall of water (hence the name) that sweeps the entire interior, including the corners.

Not suitable for dishwashing

Bear in mind that not everything is suitable for dishwasher treatment. Most chinacookware and utensils you buy will state whether they're dishwasher safe on their labelling, but if not avoid taking chances with the following:

  • Patterned/decorated fine china (may fade)
  • Gold or silver-trimmed china
  • Lead crystal glasses
  • Cast iron cookware (may rust)
  • Cutlery with wooden, plastic, bone or pearl handles (may crack or loosen)

While all wood items can be washed in a machine it's worth noting that the colour of some items may bleach out over time. Silver or chrome plated cutlery may become damaged if it comes into contact with stainless steel.

Care and maintenance

You will need to site your dishwasher as close as possible (approximately 1.2m) to your kitchen sink for ease of plumbing. It should be plumbed in before a water softener in order to maintain the performance of the machine.

All dishwashers require you to use dishwasher salt (to help with the water softening process), rinse aid (to help reduce drying time and leave dishes shiny and smear free) and of course detergent in powder, tablet or liquid form. The efficiency of '4-in-1' and '3-in-1' tablets may vary in hard water areas, and although you may find the convenience of them unbeatable, using ‘separates’ (separate detergent, rinse aid and salt) will be kinder on your wallet. Many machines also have additive indicators on the control panel which will show you when you need to refill the salt or rinse aid reservoirs.

By all means use a dishwasher freshener if you want a fresh fragrance when you open the door, but it's more important to use a dishwasher cleaner every so often to descale, degrease and freshen. Both will be redundant if you don't take time to clean out the filters where food debris gets caught. They're simple and quick to remove and rinse through.

It's vital to load your dishwasher properly to get the best out of it. Generally the top basket is for smaller, less soiled items as the spray arm is smaller, leaving the bottom basket for larger and more heavily soiled pieces. Read the manufacturer's instructions for guidance on loading and for information on items which are suitable or not for dishwashing.

Energy efficiency and the environment

Every dishwasher receives an energy efficiency grading ranging from A - G, with A being the most efficient and economical. Standardised tests, monitored by Trading Standards, are carried out across the industry and manufacturers are responsible for grading their own machines, taking into account water consumption, washing and drying performance.

The issue of water consumption may be of particular interest if you're on a water meter. All dishwashers are cold water fill, and some have time delays so that you can set the machine up to switch itself on during the night to take advantage of cheaper electricity.

All the dishwashers we stock have built-in protection against flooding activated by a sensor which closes off the inlet valve.

Some top of the range machines will detect changes in water pressure at the top of the inlet hose, and a safety valve will cut off the water supply.

You'll generally find that the more expensive the machine, the better its energy efficiency as more sophisticated energy-saving features will have been included. This is something to keep in mind, as the initial investment may make your machine cheaper to run in the long term. Top of the range machines also tend to be quieter because they have a higher level of insulation.

Installation, disposal and recycling

If you live within the delivery area of a John Lewis shop (you can check your postcode on the specific product page), your new appliance will usually be delivered by one of our vans. Our specially-trained crew and install your new appliance for you, and you'll also be able to arrange for collection and recycling of your old appliance so that we can dispose of it safely. Find out more.

We're sorry that we can't offer these services if your appliance is being delivered direct from the supplier, or if you live in a postcode where we have to deliver by courier.

You'll be offered the option of these services at checkout or when you place your order, and they must be booked and paid for at that point. We can only remove your old appliance if it's been disconnected, and once removed, it's deemed of no value and we'll be unable to return it to you.

Alternatively, you can take your old appliance to a local recycling centre to be recycled free of charge (visit to find your nearest site). If you live outside a delivery area, then your new appliance will be delivered by one of our couriers who are unable to collect, so you will need to take your old appliance to a local recycling centre.