What Is Water Softener Salt? Cost, Types, and Everything You Need to Know

While it may seem counterintuitive to add salt to your home’s water supply, water softener salt is actually important if you want to get rid of hard water. But what is water softener salt, and how does it work to remove minerals from your water supply? Learn what this simple solution is and how it works as an essential part of your water softener.

What Is Water Softener Salt and How Is It Used?

Water softener salt is a product that goes inside the brine tank, one of the most important parts of a water softener. The brine tank sits next to the resin tank, where hard minerals, like magnesium and calcium, are removed from the water. Small sodium ions on the resin bead material inside the resin tank attract the minerals and swap places, making the water soft before it leaves the water softener and goes back to your home.

However, over time, the resin beads need their sodium ions replenished and need to get rid of the mineral buildup. When this happens, the resin tank pulls brine, or salt dissolved in water, from the brine tank during what is called a regeneration cycle. This helps replenish sodium ions on the resin beads while flushing away the used brine and excess minerals.

Water softener salt is most commonly made from sodium chloride, but you can find an alternative in potassium chloride for water softeners. While potassium chloride isn’t as common, you can also find several different types of it in crystal or pellet forms.

Types of Water Softener Salts

There are many different types of water softener salts to consider. Of course, before you purchase any salt products, make sure to check your water softener manual to see what type it recommends for your model. This can help you determine whether to go with water softener crystals versus pellets.

Sodium Chloride Products

Sodium chloride-based products are the most common, least expensive, and most widely available options for water softeners. You can use rock salts, which cost less than other types of water softener salts, but they may have impurities that can cause mineral buildup in your water softener. There are also solar salts, which have fewer impurities and ring up at a similarly low cost, but they may not be a good option for water softeners in humid areas. There are also evaporated salts, which are the purest option but also more expensive than solar or rock salts.

Potassium Chloride Products

Then, there’s potassium chloride-based “salt.” This product isn’t actually salt, but it is an alternative for people who need to limit their sodium intake because it doesn’t add salt to your home’s water supply. It does tend to be more expensive and more difficult to find than traditional water softener salts. Plus, for people who need to limit potassium intake, regular water softener salts are the better option.

Salt vs. Salt-Free Water Softeners

Salt-free water softeners, or salt-free water conditioners, use a descaling process to reduce buildup from the minerals in hard water. These systems change the chemical structure of the minerals in the water rather than actually removing the minerals. In comparison, water softeners that use salts or potassium chloride use ion exchange to actually remove the hard minerals, later flushing them away with brine.

The salt-free descaling process is efficient, saving water and electricity, but salt-free water softeners can be more expensive to install. Further, salt-free systems are not recommended for homes with very hard water or homes that rely on well water.

Pros and Cons of Water Softener Salts

There are several benefits to using water softener salts if your home has hard water. Some of these benefits include:

• Removes buildup-causing hard minerals from water

• Costs less upfront than installing a salt-free water conditioner

• Most effective at preventing mineral buildup in faucets and appliances

Water softener salts may not be the right option for every household. Some drawbacks of water softener salts include:

• Creates wastewater

• Requires refills once per month or two 

• Not recommended for people requiring low-sodium or low-potassium diets

How Often to Replace Water Softener Salts

Homeowners need to refill the water softener salts in the brine tank regularly since the brine is used frequently to replenish the resin beads. It’s best to check the salt levels in the brine tank once every four to six weeks and make sure the salt level is at least 25% of the brine tank.

You’ll need to refill the water softener salt once every six to eight weeks. The brine tank should have a fill line to guide you with how much salt to add, but if yours doesn’t, keep the tank filled halfway and leave the salt level no less than 4 to 6 inches from the top of the tank. Overfilling the tank can cause salt bridges, or clumps, to form, which can cause clogs and leaks.

To refill the water softener salts, you can purchase more salts at local home improvement stores or online. You can also schedule regular refills and other water softener maintenance tasks by hiring a local water softener installation company.

How Much Water Softener Salt Do I Need?

The amount of water softener salt you need will depend on your water softener model, your water hardness, and your household size. The average household needs 40 pounds of water softener salt per month to effectively soften water.

How Much Does Water Softener Salt Cost?

Water softener salts made from sodium chloride cost $5 to $10 for a 40-pound bag, meaning you’ll spend up to $10 per month to refill the salt in your water softener. If you opt for potassium chloride instead of sodium chloride salts, expect to spend about $50 to $70 per 40-pound bag.

If you don’t yet have a water softening or conditioning system and you’re looking to get rid of the hard water in your home, you’ll want to consider installation costs in addition to ongoing costs, like salt refills. Water softener installation costs $500 to $3,000 for a standard model, or about $800 to $4,000 for a salt-free water conditioner.