If you don't know what dishwasher salt is or how to add it to your dishwasher, we've got the answers.

What is dishwasher salt?

Dishwasher salt is coarse sodium chloride. Chemically, it's essentially the same as table salt – but you should not use table salt in its place. First off, dishwasher salt comes in larger chunks, so it will dissolve more slowly and won't block any parts of the dishwasher. Second, table salt can contain other elements (such as magnesium) to prevent caking, which can affect the running of your dishwasher. 

What does dishwasher salt do?

Dishwasher salt helps to soften the water used for cleaning your glasses and crockery. It will help to prevent limescale buildup, keep the inside of your dishwasher clean and help to protect it from clogging up. If you notice that your glassware is becoming cloudy over time, it's a sign that you need to add more dishwasher salt.

How often should you top up your dishwasher salt?

Many dishwashers will alert you when it's time to top up the dishwasher salt. This may be via a flashing indicator light on the control panel. There may also be a float built into the cap of the salt reservoir. When it's full, you'll be able to see the float but when it's no longer visible, it's time to top up.

If you don't have an indicator in your dishwasher, set a monthly calendar reminder to top up your dishwasher salt. This is especially important if you live in a hard water area.

How to add dishwasher salt

Take out the bottom rack so you can access the salt reservoir in the softener unit. It’ll be in the bottom of the dishwasher and will look like a round plug with a screw-on cap.

Salt reservoir cap

Unscrew the cap. The reservoir should be full of water. If not, get a jug of water and fill it until the water level reaches the top of the reservoir. You’ll only need to do this once. After that, the reservoir should always contain water.

The salt reservoir cap has been removed

Your dishwasher should have a funnel that attaches to the reservoir. Attach it before pouring in the dishwasher salt. If you can’t find the funnel, decant your dishwasher salt into a jug and use that to pour it in cleanly. 

Filling the salt reservoir from a jug

Pour in the dishwasher salt until the reservoir is full. Different types of dishwashers will have reservoirs of different sizes but you will probably find that it can hold a large volume of salt.

Wipe up excess salt with a damp cloth. The salt in the reservoir won’t touch your crockery but any salt you spill inside the dishwasher may affect the next wash. It could scratch glassware, for example. If you’ve spilled a lot of salt, you may want to run the dishwasher empty to ensure it’s clean before you put dishes in again.

But first – screw the reservoir cap back on again tightly and replace the dish rack.

Your dishwasher is ready to go.  

If you're thinking of buying a dishwasher and you'd like to see some options, we've reviewed both a full-size integrated dishwasher, the Hisense HV651D60UK, and a slim model, the Neff N50 slimline S875HKX20G – which has smart features.