Water Softener Salt: Potassium Chloride vs Sodium Chloride

Last Updated on December 12, 2022 by Mattias

Unlike salt-free water softeners and water conditioners, a salt-based water softener system needs water to carry out an ion exchange process to remove hard mineral ions like calcium and magnesium ions that cause water hardness and replace them with sodium ions or potassium ions to produce soft water.

The two major salts in water softener brine tanks are sodium chloride (also regarded as water softener salt) and potassium chloride salt. 

These salts charge the resin beads, which release them into the water once the hard water minerals are extracted and also form a brine solution or a potassium solution (depending on the salt used) to wash the resin beads of the trapped hard minerals and prepare them for another water softening process. 

The release of these salts into the water to produce softened water helps to prevent scale buildup, dry skin, the ineffectiveness of your water heater, soap scum, the shortening of your home appliances’ lifespan, etc. 

Sodium chloride and Potassium chloride both soften water effectively. However, in the article, we will examine their significant differences and which one you should use for your water-softening system.

So, let’s get into it. 

Sodium Water Softener Salt 

Sodium chloride or sodium water softener salt occurs naturally from solar evaporation ponds or underground salt mines. 

It is the most commonly used salt among the two and is considered by many as the best water softener salt. 

It is classified into four types — evaporated salt, rock salt, block salt, and sea salt — and has two forms: salt pellets and salt crystals

Let’s look at its types. 

Types Of Water Softener Salt 

Evaporated Salt

If you want to improve the water quality in your home and keep your water pure, then this is the type of salt for you.

This salt pellet has 99.9% purity, making it the purest water softener salt. 

In addition, it prevents the formation of salt bridges and mushing in your brine tank, hence preventing clogging in the tank and the frequency of its maintenance. 

Rock Salt

Rock salt is a pebble-structured and easily accessible softener salt.

However, it has a high concentration of calcium sulfate and tends to cause salt bridging, which could lead to clogging in the brine tank.

Also, it doesn’t dissolve in water easily like evaporated salt. 

Block Salt

As its name implies, this softener salt is block-like and cannot go under the brine tank until its water level is high.  

Sea Salt

Sea salt, also called solar salt, is a highly pure salt from solar evaporation ponds.

It can be accessed easily and tends to cause salt bridges lesser than rock salt.

Potassium Chloride

Potassium chloride also occurs naturally, softens water effectively, and exists in the form of potassium chloride pellets.

Read also: 12 Best Kitchen Faucets For Hard Water + Buyers Guide

Water Softener Salt Vs Potassium Chloride: What Are Their Differences?

Health Concerns 

Potassium chloride plays a more important role in human health than sodium chloride. 

It is an essential nutrient that aids the proper functioning of organs and nerves. 

It is also a great alternative for people with health conditions such as heart disease, high blood pressure, etc., and people on a low-sodium diet.

The use of potassium chloride salt will also ensure the reduction of sodium in your drinking water and your general sodium intake.

In addition, people who do not like the salty taste of water softened with sodium chloride can go for potassium chloride, as water softened with it tastes like table water. 


Potassium Chloride is more expensive than sodium chloride, and the amount of potassium chloride used in a potassium water softener is 2 to 3 times more than the amount of sodium in a sodium chloride softener in the same period.

The high cost of potassium chloride can be attributed to the resources spent to mine it. 


Sodium Chloride is more widely available than potassium chloride salt.  


Both sodium chloride and potassium chloride can effectively handle your home’s water hardness problem. 

Environmental Friendliness

Unlike sodium chloride, potassium chloride is environment-friendly and can improve the soil’s stability and vigor.

Also, the water that is softened using potassium chloride is great for plant health and animal consumption, as opposed to water softened using sodium chloride, which could affect the health of plants if used to water them or the health of animals if used quenched their thirst.

Water Softener Salt Vs Potassium Chloride: Which One Should You Use In Your Water Softener?

When it comes to water softening, both salts produce excellent results. However, potassium chloride-based water softeners need to use 2 to 3 times as much salt to soften water the way sodium chloride does, giving the latter an edge. 

Also, sodium chloride has a comparatively lower price than potassium chloride. 

However, potassium intake has more health benefits than sodium intake, as the former is an important nutrient that contributes to the good health of humans and plants.  

In addition, if you are on a sodium-restricted diet or don’t like the taste of water softened with sodium salt, you should go for potassium chloride salt.

But, if you are restricted from drinking softened water, you can install a reserve osmosis system and connect it to your tap water to remove the potassium and sodium content.

You must consider the above factors and choose the best salt for your water supply.

Read also: How To Add Salt To Water Softener


Does potassium-softened water hurt plants?

No, since it’s a plant nutrient, it works fine for soils and plants.

Why is potassium water softener so expensive?

It costs much more to extract potassium chloride from the earth than mining sodium chloride. 

Can I switch my water softener from salt to potassium?

Yes, it’s possible to switch from sodium chloride to potassium chloride.

Can all water softeners use potassium?

Yes, most softeners will do it easily since they can’t tell the difference between potassium chloride and sodium chloride. 

Read also: Can You Use Water Softener Salt To Melt Ice?

Water Softener Salt vs Potassium Summary

I hope you enjoyed this article comparing these alternatives.

As you discovered, there are many things to consider when choosing between potassium and sodium. Hopefully, this article helped you to get the answer you were looking for. Good luck!