Use of Salt In a Dishwasher

Everyone with a dishwasher is familiar with dishwashing detergents. But not many know about the importance of using dishwasher salt. If that sounds like you, don’t worry. You’ve come to the right place.

Dishwasher salt is used to soften the water used for washing your plates and other dishes. It’s a necessity for people who live in areas supplied with hard water, which contains higher dilutions of minerals like calcium and magnesium. These minerals will leave unsightly marks and stains on your dishes if not removed by the appliance’s water softener, which requires dishwasher salt to function correctly.

Let’s take a deeper dive into everything you need to know about dishwasher salt.

What Is Dishwasher Salt?

Dishwasher salt is simply salt that’s loaded into a special compartment in the appliance to soften the water used to clean dishes.

That compartment is known as a water softener. Dishwasher salt is similar to the regular table salt that’s used to season food. However, it has unique qualities that make it suitable for use in a dishwasher. 

Therefore, regular table salt is not a substitute for dishwasher salt, and we’ll see why later in this article.

Even though everyone is familiar with dishwashing detergent, not everyone has used dishwasher salt before.

That’s because dishwasher salt is only used in locations where the municipal water supply provides hard water to the appliance.

Unfortunately, hard water is not suitable for washing dishes, which is why dishwashers need water softeners supplied with dishwasher salt.

What Is Hard Water, And How Does It Affect Dishwashers?

Depending on where you live, you might find that your household is being supplied with what’s called ‘hard water’. That’s the kind of water that contains plenty of diluted minerals, most notably higher concentrations of calcium and magnesium.

Hard water can reduce the effectiveness of washing anything with soap, whether you’re showering, doing your laundry, or washing your dishes. When washing something using hard water, you’ll find that you need much more soap or detergent than usual to get the job done correctly.

Connect with an Appliance Repair Tech

Click here to use the chatbox to speak with one of our technicians.
No in-home service calls. No appointments.

Related: Dishwasher Problems Caused by Hard Water

Don’t worry. Hard water is harmless to your dishes, other than the marks it leaves behind.

However, that appliance will have a much more challenging time making your place settings spotless. Without a water softener with dishwasher salt to soften the water, your dishes will likely come out covered in hard water residue that looks like spots or thin film coating each item.

How Does A Dishwasher Water Softener Work?

To prevent the problems caused by that hard water residue, modern dishwashers come with a water softener as a standard feature. Thanks to special synthetic resins, the water softener causes the calcium and magnesium in hard water to attach to it.

That water softener is continually being used, so it won’t take long for those resins to become saturated and lose their effectiveness. Thankfully, the resins can be regenerated using dishwasher salt, and the water softener can continue to work effectively.

As a result, the water that flows into the dishwasher is softened and can then be used to make your dishes inside spotless.

Why Is Dishwasher Salt Necessary?

As mentioned above, the role of the dishwasher salt is to renew the special resins on the appliance’s water softener. Those resins are responsible for removing diluted minerals from hard water, but they become saturated and less effective over time.

So, dishwasher salt helps regenerate those resins and keep the water softener working as it should whenever you wash dishes.

What Are The Benefits Of Using Dishwasher Salt?

Dishwasher salt offers several significant benefits to your appliance. The two most important benefits are:

  • Prevents Watermarks And Other Spots: Of course, the primary benefit of using dishwasher salt is to ensure that dishes come out of the appliance looking spotless. More importantly, that means the dishes will be free of watermarks and other unpleasant spots or stains usually caused by hard water.
  • Prevents Limescale: Hard water isn’t just bad news for your dishes, but it also negatively affects the dishwasher itself. Over time, the diluted minerals in hard water can cause buildups known as limescale. Seeing as how water continually flows through your dishwasher, that limescale buildup could cause its components to eventually malfunction.

Can You Use Regular Table Salt As A Substitute?

No, you cannot use regular table salt as a substitute for dishwasher salt. You must also never use cooking salt, sea salt, or any other kind of salt as a substitute.

As mentioned earlier, dishwasher salt is different from any other kind because it has unique qualities that make it suitable for use in a dishwashing appliance. Dishwasher salt is a more granular type of salt that dilutes very slowly. That means it will not block the water softener or cause any problems for the appliance.

If you were to use the wrong type of salt, you could cause your dishwasher to clog. The salt used for cooking, for example, is incredibly fine and can quickly get stuck if it gets wet.

So, to prevent any problems, always use the correct type of salt for your dishwasher’s water softener.

How Much Dishwasher Salt Do You Need?

Knowing how much dishwasher salt to use is very straightforward, as there are no specific measurements involved. Instead, all you have to do is insert enough dishwasher salt to fill the compartment to its maximum capacity.

Of course, you should try to avoid overfilling it. If there is any excess salt around the compartment, be sure to wipe it up completely before you use the dishwasher again.

With every load of dishes washed, the amount of salt in that compartment will gradually reduce. To reduce the frequency of refilling the salt, be sure to fill the compartment to the top.

How To Know When Your Appliance Needs More Dishwasher Salt

There are three ways to know when to top-up your dishwasher salt compartment:

  • When The Indicator Turns On: Most dishwasher models today include an indicator light to let you know when salt levels are too low in the water softener. When this indicator turns on, you will know that it’s time to refill the compartment with dishwasher salt. Remember to fill it to the top.
  • On A Regular Schedule: Instead of waiting for the indicator to let you know that the appliance has run out of salt, an excellent practice would be to refill it on a regular schedule. Doing this once a week is typically enough. However, if you use the dishwasher more often than usual, like in a large household or a professional setting, you will have to refill dishwasher salt more often.
  • When Hardwater Marks Appear: Watermarks and spots on your dishes are clear indicators that your dishwasher has run out of salt. However, by this time, it might be a little too late. Your dishes have already been stained after being washed with hard water and will need to be rewashed.

How To Top-up Your Dishwasher With Salt

When the time comes to top-up your water softener with dishwasher salt, here are the steps to follow:

  1. Locate: If this is your first time, you will need to locate and identify the salt reservoir in your dishwasher. Typically, you will find it at the bottom inside the dishwasher, under the lowest rack. To be sure, refer to your dishwasher user manual for guidance.
  2. Access: Remove the bottom dishwasher rack to gain access to the reservoir. Then, remove the protective cap. It is helpful to shine a light in there and see just how empty or full the reservoir might be, so you can avoid overfilling it with salt.
  3. Pour: Next, pour the dishwasher salt into the reservoir. You can minimize any spills by using a funnel that reaches into the reservoir. Be sure to pour the salt into the funnel in small increments to avoid overfilling and spilling it all around.
  4. Clean: When the reservoir is filled to its maximum capacity, gently remove the funnel and tap it slightly so any leftover salt will fall. Then, seal the reservoir firmly and remove all salt that might have been spilt around the reservoir’s cap. 
  5. Rinse: After replacing the bottom rack, close the dishwasher and run the shortest cleaning cycle available. The purpose of this final step is to wash away any excess salt that might have spilt around in the dishwasher, which is why the appliance must be empty.

Related: Why Is Dishwasher’s Detergent Door Not Opening?

Always Clean Up Excess Dishwasher Salt

You’ll notice that this has already been mentioned several times above, but it’s worth repeating once more. The reason why it’s crucial to clean up and rinse away any excess salt because it can be harmful to your dishes when left inside the dishwasher.


Dishwasher salt is granular and not fine like regular table or cooking salt. That means any excess dishwasher salt that’s washed around will scratch any glassware that you’ve loaded into the dishwasher, causing unsightly damage to them.

Thankfully, this problem is easy to prevent with a pre-wash while the appliance is empty.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed. Protection Status