How to Add Salt to a Water Softener? (Our Expert Explains)

Even someone who knows nothing about water softener systems could probably guess that a salt-based water softener needs salt.

If you’ve just bought a water softener and you’re a complete newbie to adding salt to the brine tank – maybe you don’t even know which tank to add the salt to – this guide is for you.

We’ve kept things as simple as possible. Below, you’ll find a quick step-by-step guide on how to add salt to your water softener.

Plus, if you fancy some extra reading, we’ve answered your pressing questions about how much, and what kind of, salt you need, and shared a bit about why it’s so important to top up your water softener salt level.

🧂How to Add Salt to a Water Softener

To add salt to your water softener, follow these steps:

  1. Locate your water softener’s brine tank. The brine tank might be labeled “salt” or “brine”. If it isn’t labeled, it’s the shorter tank that contains salt (open the lid and it’ll become pretty obvious quickly).
  2. Check your salt levels. If the brine tank is half-full of salt, or less, you need to add more salt.
  3. Check that the tank is clean, with loose, free-moving salt. If you notice any chunks of salt, use a broom handle to break them up.
  4. Pour in the salt. Take a bag of water softener salt and pour the salt into the brine tank. Get someone to help you if the bag is heavy! Continue adding salt until you reach the fill line, which should be marked about three-quarters of the way up the tank. This is where the water level will reach, so don’t add salt any higher.
  5. Shut the lid of the brine tank. You don’t need to do anything else from here. The softener will fill the tank with water as needed. All you need to worry about is topping up the salt.
Adding Salt to Water Softener

⏲How Much Salt Does a Water Softener Use?

About 6-8 pounds of salt are needed per water softener regeneration, depending on the size of the system. This equates to about one 40-pound bag of salt each month, or 12 40-pound bags of salt each year.

Let’s break it down some more.

Water softeners usually regenerate at least once a week. At this rate of regeneration, if a water softener regenerates between six and eight times per month, it should use a single 40-pound bag of salt per month.

Water softeners are pretty efficient, and the amount of salt they need today is far less than the traditional salt-based softener used to need.

Still, there are things you can do to minimize your salt usage, so you’re buying salt less frequently.

Our top tip is to buy high-purity salt with at least a 99.6% salt content. This means the softener will be able to use a higher amount of salt with every salt top-up, with less dirt and organic matter clogging up the brine tank.

💵How Much Does Water Softener Salt Cost?

The average monthly cost of water softener salt is $2 to $15. You don’t have to spend a fortune to run a water softener.

The cost of water softener salt depends on a few factors:

  • The size of your water softener – the bigger the system, the more salt in the brine tank it’ll use, the more you’ll need to buy per month
  • The type of salt you buy – the purer the salt, the better it is, therefore the more expensive it is
  • The quantity of salt you buy – generally, the more bags of salt you buy upfront, the less you’ll spend per pound
  • Where you get your salt from – you can get much better deals if you shop around online versus buying salt from your local home improvement store
  • Your water usage – the more water you use, the more frequently the softener will need to regenerate, the greater the amount of salt you’ll need

🥇The Best Salt to Use in a Water Softener

We know by now that the brine tank is something of a fuel tank, and salt is the fuel. Salt is an essential water softener ingredient – but what type of salt is best?

putting salt to use in a water softener

When it comes to adding water softener salt, you have a few options:

  • Evaporated salt – highest purity
  • Solar salt – second-highest purity, but not as soluble
  • Rock salt – not as pure as solar salt; contains calcium sulfate
  • Block salt – very pure, but requires water levels to be raised in the brine tank
  • Potassium chloride – a salt alternative that usually comes in pellet form

If you want to become something of an expert on the best salt and potassium chloride brands for water softeners, check out our best water softener salt guide, which shows our tried-and-tested softening salt favorites.

⌚️When Should You Add Salt to a Water Softener?

You know the important part – how to add salt to your softener, and how much salt to add. But now you’re probably wondering: “When should I add salt to my water softener?

Follow the tips below, in this order:

Tip 1: Check the Brine Tank

The most obvious way to find out when to add salt to your softener is to check the brine tank.

If you’ve just bought a softener, get in the habit of checking the salt level once a day. You’ll quickly become used to how much salt the system uses within the span of a week, and how long it takes for the salt level to fall beneath half-full.

Eventually, you’ll be able to schedule salt top-ups based on your softener’s salt usage. Most seasoned water softener owners check their brine tanks once every three or four weeks, knowing what their water softener requires, and refill their salt as necessary.

Tip 2: Consider your Water Softener’s Age

You should now have a good idea of how often salt top-ups are needed in your softener. But you’ll need to adjust your routine as your softener ages.

Water softeners have a lifespan of 10-20 years. Just like humans, water softeners aren’t quite as sprightly towards the end of their lives as they are at the beginning.

When your softening system surpasses 7-10 years old, you’ll probably notice that it needs more salt to do its job. This is especially the case when the resin bed needs replacing. You shouldn’t need significantly more salt than usual, though, unless there’s a problem with the softener.

Think it’s time to replace your system? See our picks of the top rated water softeners in 2022

Tip 3: Account for Salt Bridges

Beware of salt bridges! They make you think that your brine tank is full when it might actually be empty.

A salt bridge is a layer of salt that forms at the top of the brine tank. Underneath this layer is usually an air pocket, and underneath the air pocket is whatever brine solution the tank still contains.

salt bridge in a water softener

If you’re feeling smug about how little salt your water softener seems to need, it might be too good to be true. Use a small shovel to jab the top layer of salt in the tank. If you have a salt bridge, the salt will cave in, and you’ll make a hole that reveals your actual salt level below.

⚠️Why it’s Important to Add Salt to a Water Softener

Water softeners rely on salt to eliminate hard water minerals, improving water quality, in the ion exchange process. Without sodium chloride (or potassium chloride), there would be no sodium ions in the resin beads that could be exchanged with hard minerals in the water softening process.

Ensuring your water softener’s salt supply is consistent has the following benefits:

Allows for Proper Water Softening

A water softener works only when the brine tank contains salt. Without enough salt (or any salt at all) in the brine tank, your softener won’t be able to regenerate properly. And without a proper regeneration cycle, the resin beads can’t be properly restored with sodium.

Imagine that your softener completely ran out of salt pellets. The system would end up regenerating with plain water. The resin beads would contain no sodium chloride, so the softener wouldn’t be able to replace the water hardness minerals in the water that flowed through the resin tank.

The result? Your water would be just as hard when it left your softener. Without soft water, you’d end up with the same hard water problems that you’d experienced before, including:

  • Dry skin and hair, due to hard water’s inability to lather with soap, forming a sticky layer of soap scum
  • Cleaning challenges caused by a buildup of limescale on the surfaces in your kitchen and bathroom
  • Hard water damage to water-using appliances like your hot water heater, reducing their lifespan and affecting their performance
  • Unsightly hard water stains in your toilet, around your faucets, on your shower screen, and on your showerhead

In short, underestimating how much salt you need, or forgetting to add salt entirely, will bring back the water hardness problems that you’re trying to avoid.

cleaning limescale off faucet

Helps you to Spot Issues in the Brine Tank

Sticking to a schedule for adding salt pellets to your water softener means that you’ll be aware of how much salt your softener is using to produce soft water.

You’ll realize pretty quickly if your water softener isn’t using salt at its usual rate. Get into the habit of conducting regular maintenance checks when you top up your salt, looking out for the telltale signs of bridging and mushing, such as:

  • Encrusted salt that sticks together
  • Issues with draining in your brine tank
  • Salt levels that don’t seem to lower after a regeneration cycle

Mushing clogs up the bottom of the brine tank, while bridging clogs up the top of the tank. Both of these are bad signs for your softening system, preventing brine from getting into the resin tank. This hinders the softening process, eventually preventing soft water production altogether.

Ensuring your brine tank is at least one-quarter full, but isn’t filled over the maximum fill line, will prevent salt bridging. You may need to use less salt if you’re filling the salt beyond your water level, and you may need to clean out the brine tank and reset the system.

Dealing with salt mushing and bridging is annoying, but you can avoid these issues by adding the proper amount of salt in the brine tank, ensuring the salt level isn’t too high, and performing maintenance checks while you’re at it.