What Is The Best Water Softener Salt: A Definitive Guide

What Is The Best Water Softener Salt A Definitive Guide

Anthony Barnes

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A good water softener can run for decades, providing you and your family with safe and soft water. The salt is a key part of this.

Salt helps to remove the hard calcium and magnesium minerals from water, replacing them with sodium. But you can’t just add salt from the local superstore and expect it to do a good job.

The salt helps transform your hard water to soft water, and supports the long-lasting function of your water softener systems.

Take a look at this guide to find the best salt for your salt-based water softeners

Why Is Water Softener Salt Important (And Why Do You Need The Right One)?

Water softeners are a must-have for homes with hard water. They’re used to remove the minerals that can build up inside pipes and fixtures, and make water easier on your skin, hair, and clothes.

However, water softeners (see also ‘Salt Vs. Salt-Free Water Softeners‘) need salt for optimal function, and not all salt is created equal. There are many types of salts that you can use with your water softener, but some of them won’t do much good.

A water softener works by a process known as “ion exchange”.

During ion exchange, the hard minerals in your water, such as calcium and magnesium, pass over the salt from the brine tank that is embedded in the resin bed.

The sodium ions from the salt are then switched with the calcium and magnesium ions. The water mineral levels are reduced, and you have softened water.

The type of salt you choose will affect how well your water softener (see also ‘Leaking Water Softener? Reasons And Solutions‘) functions. Impure salt can cause grime to build on the resin bed, needing regular maintenance.

But the right salt can ease the process, giving a better quality to hundreds of gallons of water.

In this article, we’ll explain what makes each type of salt different, and why you should pay attention to the quality of the salt you buy.

Different Types Of Water Softener Salt

There are several kinds of salt you can use with your home water softener. Each has its own benefits and drawbacks, so choosing the best one requires careful consideration. 

Potassium Chloride: The Non-Salt Salt

Potassium Chloride The Non-Salt Salt

Despite being a salt, potassium chloride is typically seen as the “non-salt” option for water softeners.

Potassium chloride pellets are typically used by those who are worried about the effect adding salt to water might have on their health levels.


Reduced sodium levels are the major benefit to potassium chloride, but the actual advantages are small.

Very little salt actually passes into the water supply during the softening process, and for the majority of households, the sodium level is perfectly acceptable.

However, for those with a health condition that requires close monitoring of sodium intake, potassium chloride can be the best choice for water softener salt.


The biggest disadvantage to potassium chloride is that it doesn’t perform as well. Rather than the ion exchange key to true softening, potassium chloride crystallizes the minerals in the water, acting as a water conditioner.

It can reduce the build-up of scale, but not as effectively. Potassium chloride typically costs more, and delivers a poorer performance. 

Rock Salt: Cheap, But Hard Work

Rock Salt Cheap, But Hard Work

If you want the cheapest salt possible, rock salt is often the way to go. Rock salt is cheap because it’s made from naturally occurring deposits of salt found underground.

It’s also very effective at removing minerals from water, but can make maintaining the softener hard work.


Rock salt is affordable and easy to buy. Rock salt is sold in many stores, and can often be bulk purchased at a reduced cost. 


The low-cost of rock salt is often related to a lack of purity. Mined from the ground, rock salt can contain other minerals.

Over time, these will form a layer of grime in the brine tank, leading to a solid layer of salt known as a salt bridge. If you plan on using rock salt, prepare to spend time cleaning and caring for the water softener.

Another disadvantage of rock salt is the source. Rock salt is mined from the ground, and there are worries this process can lead to sinkholes, and destroy ecosystems.

If you want to use rock salt from a sustainable source, be prepared to pay extra.

Sea Salt: Better, But Not The Best

Sea Salt Better, But Not The Best

Sea salt is harvested from the ocean using a drying process that leaves behind salt crystals. As a salt with minimal processing, sea salt can sometimes contain trace minerals. 

Sea salt is a decent choice for water softener, although as with the others, it has advantages and disadvantages. While it isn’t quite the best, it’s not the worst.


An advantage to sea salt is how easy it is to buy. Sea salt is widely available, and certain brands are inexpensive. With fewer minerals than rock salt, a water softener containing sea salt is easier to clean and maintain.


The lack of processing used to create sea salt can result in some varying quality. While some brands are very pure, others have a higher mineral content. Finding the right salt can be a process of trial and error.

Evaporated Salt: The Best Water Softener Salt

Evaporated Salt The Best Water Softener Salt

Our preferred choice for water softener salt is evaporated salt pellets. These are created using an evaporation process involving steam and water, which creates crystals.

These crystals are dried, screened, and processed, creating the cleanest salt pellets. Evaporated salt can be up to 99.99% salt.


The purity of evaporated salt reduces the build up of grime and solidified salt in the brine tank, requiring less maintenance and offering a better water quality.

Because the softener can run efficiently, it can perform for longer. 


Evaporated salt pellets can be harder to come by, and are typically more expensive. However, the extra cost can be offset by the purity of the salt.

The superior performance of evaporated salt allows the water softener to perform at its best, saving you money (and time that would be spent on maintenance) in the long run.

The Best Brands Of Water Softener Salt

Choosing the best type of salt is only the first part of your decision. Next, you have to choose the right brand.

Purity is a big factor in an effective water softener salt, and it can vary hugely from brand to brand. Here are some of our top choices for salt brands:

Diamond Crystal

Diamond Crystal

Diamond Crystal is one of the most popular kosher salt brands in the United States, and also a fantastic choice for a water softener salt.

Their Bright & Soft Water Softener Salt Pellets contain 99.8% pure salt, while their Solar Naturals Salt Crystals contain 99.6% pure salt.

If you live in an area with a high iron content in the water, Diamond Crystal also makes Iron Fighter, formulated specifically to tackle iron build-up. And they have a low-sodium potassium chloride softener as well.

Diamond Crystal is a versatile and affordable brand, with a proven history of quality. 

Morton Salt

Morton Salt

If you’re looking for a budget-friendly and easy to purchase option, Morton Salt is another great choice. Like Diamond Crystal, Morton Salt is a brand known for their quality, and they’re a big name in salt.

They have a fantastic product range, including both potassium chloride and evaporated salt, so you can find what you need for your water. The large bags are also strong and easy to handle, making spills less likely.

Morton Salt water softener salt is widely available from hardware stores.

Windsor Salt

Windsor Salt

For good salt on a budget, try Windsor Salt. This is another brand with a long history of quality, and the water softener salts from Windsor Salt are clean and effective.

Although the range is slightly smaller, you should still be able to find an option that works for your water supply.

Nature’s Own

Nature's Own

Although potassium chloride isn’t the right choice for everyone, some people do require the low sodium alternative.

If you think this is the right choice for you, there are few options better than Nature’s Own Potassium Cubes.

The unique formula is one of the most effective potassium chloride pellets around, softening and rejuvenating water without increasing sodium levels.

Although it is slightly more expensive, the high quality of the product makes it one worth considering.

The Best Water Softener Salt For Water With A High Iron Content

If you live in an area where the water has a lot of iron in it, then you’ll want to make sure you have a quality water softener.

The salt can support this function, but shouldn’t be the sole thing you rely on to remove iron.

Instead, the best thing to do is combine a quality salt that helps the water softener run effectively with a filter dedicated to removing iron. 

Water softeners can remove iron, but it then becomes embedded in the resin beads.

For areas with a low concentration of iron in the water, this shouldn’t cause a problem. However, if you live in an area with a high amount of iron, then consider an iron filter. 

Even if the water softener does remove some iron, it won’t clear it completely.

The best water softener salt for water with a high iron content is a pure salt. These salts reduce the build up of grime on the resin bed, so when it comes to maintenance, you can focus on removing the iron. 

However, some brands do make salts designed to tackle the iron in the water.

Diamond Crystal, for example, manufactures Iron Fighter Water Softener Salt, which is formulated for water with an increased iron content. 

The Best Water Softener Salt For Well Water

Our advice above is mostly centered on the water supply provided by a municipality. This is often easier to care for, as it will already have been treated, and you can find a fairly accurate hardness estimation online.

Well water is more tricky to deal with. Well water can contain a wide variety of chemicals, minerals, and other substances.

As such, it can be difficult to know how to maintain it properly.  Although the advice we’ve given can apply to well water, there are a few other factors that you must consider.

A private well will need to be regularly tested to ensure that it is safe to use.

Alongside regular water tests, consider the construction of the well, how consistently it’s maintained, and any industrial activities that might affect the supply.

Together, this information can help you to set up a filtration system, and decide on the best water softener salt.

Final Thoughts On Best Water Softener Salt

There are many types of water softener salt available. Our top pick is evaporated salt, thanks to the purity of the crystals.

With fewer minerals within the salt, there’s less of a grime build up in the mineral tank, and a reduced risk of salt bridges. Although a more expensive pick, the performance quality of evaporated salt makes it better overall.

However, both rock salt and sea salt can remove minerals, and different purity levels are available. A cost-effective choice, if you use sea or rock salt, make sure you trust the brand. 

For those with a health condition that requires strict sodium monitoring, potassium chloride may be your best choice.

The non-salt salt, potassium chloride has a reduced sodium level, while still removing hard minerals from your water.

We hope this guide has helped you find the right salt for your water softener, and to understand the differences between the choices.

Frequently Asked Questions

Which Water Softener Salt Is The Best?

Evaporated salt is widely recognized as the best salt for a water softener, thanks to a high degree of purity.

Evaporated salt is produced by many quality brands, although it can be a more expensive option.

Sea salt is also good, although it lacks some purity, and potassium chloride is best for those with health concerns.

Does It Matter What Salt I Use With My Water Softener?

Yes, the type of salt used with your water softener does make a difference. A lower quality salt can lead to salt bridges and a build up of grime, plus a less effective performance overall.

What’s The Difference In Performance Between Water Softener Salt And Potassium Chloride?

Salt removes minerals from water via ion exchange, replacing hard minerals with soft sodium.

Potassium chloride doesn’t switch the minerals, but crystallizes them, so they can’t stick and build up. Both perform well, but salt tends to perform better because the minerals are neutralized.

Is Water Softener Salt Safe To Eat?

Water softener salt is safe to eat, and it is consumed in low amounts once it’s cycled into the water.

However, you probably don’t want to use it for seasoning. Water softener (see also ‘Water Filter Vs. Water Softener’) salts typically come in pellets that are tough to sprinkle, and the salt doesn’t go through the same rigorous processing treatment as table salt.

Is Water Softener Salt And Table Salt The Same?

Although they both might come from the same source, table salt goes through a rigorous processing treatment to make it safe to eat in larger quantities.

Water softener salt is edible in small amounts, but it isn’t processed enough to be used as a seasoning. 

How Often Should I Refill The Brine Tank?

The brine tank should be refilled every month at least. 

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By Anthony Barnes

Anthony Barnes is the founder of Water Heater Hub and a second-generation plumber by profession. Before developing Water Heater Hub, Anthony Barnes was a full-time plumber, and he has undertaken a wide variety of projects over the decades. As a second-generation plumber, it was easy for Anthony to get used to the technicalities of all from a tender age