How Does Reverse Osmosis Remove Chlorine? 

Reverse osmosis is an effective water filtration technique that can help remove contaminants from water, including chlorine. But how does reverse osmosis remove chlorine? The carbon block filter in an RO system remove up to 98% of chlorine from water.

Do you know how filthy the tap water really is? Household tap water contains several harmful chemicals. If you are on a municipal water source, the chemical that we are talking about here is chlorine or chloramines.

More than 86% of U.S. households receive chlorine in their tap water.

Chlorine and chloramine are used to disinfect and treat water for bacteria and viruses. However, ingesting chlorine in water has various side effects such as:

  • Vomiting
  • stomach ache
  • diarrhea
  • dryness
  • irritation

A higher dose of chlorine can also lead to severe chlorine poisoning, which can even be fatal. Therefore, it is advised to remove chlorine from water. 

One of the best ways to do so is reverse osmosis (RO). Nowadays, many industrial and at-home water filtration units use RO to purify water. 

Related Article: Reverse Osmosis vs Distilled Water

Key Takeaways | How Does Reverse Osmosis Remove Chlorine? 

  • Reverse osmosis (RO) is a highly regarded, effective, and convenient water purification method on the market right now. 
  • Reverse osmosis systems remove dissolved salts, colloids, odors, bacteria, organics, pyrogens, and pollutants from water, including chlorine, fluoride, lead, pesticides, fluoride, arsenic, pesticides, pharmaceuticals, and much more. 
  • The carbon filter in an RO system removes 95-99% chlorine from water. 
  • Reverse osmosis filtration is automated, cost-effective, and easy to maintain. 
  • As with any other product, RO filters also come with their own set of pros and cons
  • Before purchasing an RO system, understand how it works and where it will be placed in your home. 
  • Get a long-lasting reverse osmosis system that suits your budget and other preferences. 

How Does Reverse Osmosis Remove Chlorine?

Reverse osmosis carbon combination filtration provides chlorine-free water for your household. It is usually connected to the plumbing in your home.

A typical RO water filtration system looks pretty complex with multiple filters, tubes, connectors, a membrane, and a tank. The main components of an RO system are carbon filter, sediment filter, and membrane. 

How Does Reverse Osmosis Remove Chlorine? 

Let’s take a closer look at what function each of these components performs: 

Sediment filter:

Removes solid particles such as dirt, dust, and rust.

Carbon filter:

Removes volatile organic compounds (VOCs), chlorine, and other contaminants.

Semi-permeable membrane:

Removes 98% of TDS (total dissolved solids). The membrane is the most significant component of a reverse osmosis system.

Now, let’s find out how does RO remove chlorine and produces super pure drinking water for your family. 

How Does RO remove Chlorine?

How a reverse osmosis unit exactly works depends upon the number of prefilters and post-filters the plant has. Depending upon the model, an RO system can include 3, 4, or 5 filtration stages.

However, this is how a 3-stage RO water system works: 

  • Water enters the prefiltration stage, where it passes through the filters. The filter removes chlorine and sediments that can damage and clog the RO membrane.
  • Then the filtered water enters the membrane to eliminate any dissolved particles.
  • Then the clean water is passed to the storage tank until it is complete.
  • After water exits the storage tank, it passes through a postfilter to polish the drinking water before it enters a dedicated faucet. 

Now you will get clean water every time you turn on your faucet. 

In this way, water purification systems use reverse osmosis to clean water. However, the chlorine in water can damage the membrane over time. 

Therefore, manufacturers use a carbon filter to remove chlorine before the water passes to the membrane to avoid RO membrane chlorine damage

What Will Reverse Osmosis Remove From Water?

How Does Reverse Osmosis Remove Chlorine? 

You know reverse osmosis removes contaminants from water. But you must be wondering what exactly does it remove? Does reverse osmosis remove chloramine and chlorine only? 

Basically, RO filters contain Granular Activated Carbon (GAC) to capture and absorb different types of impurities from water. These include chlorine, fluoride, lead, nitrates, arsenic, pesticides, herbicides, etc. 

However, the RO membrane is the real filter. The membrane captures everything – from microscopic particles like ions and molecules to dissolved biological species like bacteria, viruses, etc. 

How Much Chlorine Does RO Remove?

A good reverse osmosis water filtration system with carbon blockers removes up to 98% of chlorine in the water.

Basically, the activated carbon absorbs most of the chlorine in the water while the remainder is filtered through the membrane.

The RO membrane has a pore size of nearly 0.0001 microns, allowing clean water molecules to pass through, filtering out dissolved and suspended particles, including organic compounds and contaminants such as fluoride and chlorine.

To further enhance the filtration process, new and improved RO system models include additional coagulants, activated charcoal filters, and sediment filters along with the membrane to reduce chlorine concentration levels of the water significantly.

Furthermore, post-filter treatments such as U.V. radiation sterilization also reinforce dichlorination efficiency. Some additional filters also re-mineralize the treated water. This removes up to 99% of chlorine from water and makes it healthier to drink.

Thus, if you’ve been wondering does filtered water have chlorine, the answer is no. After a thorough reverse osmosis purification, you get chlorine-free water.

How Does Reverse Osmosis Remove Chlorine? 

Why Should You Get A Reverse Osmosis System?

There are many reasons why most U.S. residents choose reverse osmosis filtration. Here are the top benefits:

Why Should You Get A Reverse Osmosis System?

No electricity cost:

An RO system does not need electricity to run as it uses water pressure to operate.

Highly Effective:

Reverse osmosis is a highly effective filtration technique as it removes nearly all contaminants.

Better Taste:

You don’t need to spend extra money buying water bottles in the grocery, as reverse osmosis gives you clean and better-tasting tap water.

Flexible Price Range:

One of the best things about reverse osmosis systems is that they are available in an extensive price range.

Common Disadvantages of Reverse osmosis Systems

Why Should You Get A Reverse Osmosis System

There are many advantages of reverse osmosis. People use reverse osmosis filters to remove chlorine and chloramine from the water supply for various reasons, including order taste and harmful side effects of chlorine.

Now let’s take a look at some of the drawbacks of the reverse osmosis system:

1.    Excessive Water Wastage

One of the most significant downsides of reverse osmosis is the amount of water that is wasted.

Since RO is a cross filtration system, it wastes 3 to 20 times more water than it produces. According to studies, an RO system is only 25% efficient.

This is bad for the environment and a concern for homeowners (because it leads to higher water bills as there will be more water consumption).

2.    Removal of Healthy Minerals

Another significant drawback of reverse osmosis water filtration is the removal of healthy minerals from water.

Reverse osmosis filters not only remove nasty contaminants but also absorb some healthy minerals, including magnesium, potassium, calcium bicarbonates, etc.

Moreover, extracting these minerals also decreases the pH level of the water and makes it more acidic. Even though the acidic level is not high enough to harm humans, the lower pH corrodes plumbing pipes and strips copper and lead, which adds toxic metals to the water.

3.    Maintenance Required

Reverse osmosis filtration systems are high maintenance for homeowners as you need to change filters regularly.

Related Article: How Often Should You Change Reverse Osmosis Filters?

While some people attempt to fit these filters into the house, the process can get complicated and requires professional installation and maintenance to function correctly.

4.    High Cost

Reverse osmosis filters can cost thousands of dollars, making them considerably more expensive than other water purification systems.

Plus, you need to change the filters and the membrane regularly, costing hundreds of dollars.

The cost of replacement filters varies greatly depending on what RO system you get. For example, the more popular brand name filters are a bit more expensive.

That said, you can also find low-priced filters on Amazon, but they probably won’t be the best quality.

How to Select an RO System

Like any other product on the market, there are different types of reverse osmosis water filter systems available. This makes it hard for homeowners to find a suitable brand that will work for their home with optimal efficiency.

Therefore, we have constructed a guide on the basics you need to know before purchasing a reverse osmosis water filter.

Here is how you can select the best RO water filter system for your home:

Set Budget

The more expensive models often have extra filtration stages and can filter a larger volume of water at a time. They also come with extra special features like auto flush, U.V. purification, remineralization, etc.

Talking about the cheaper models, they are made of low-quality material and typically don’t last A long time.

Finally, the midrange models are the most popular choice because they have some of the features of the higher-end models and get the job done well for most people’s needs.


What size reverse osmosis system you want is also an essential consideration as it should be able to fit the space you have available.

For example, if you want to keep it on the counter or install it under the sink, you need to buy an RO filter that isn’t too bulky. So, make sure you buy a model that isn’t too big and can easily fit into the available space.

The best thing to do is to measure the space you have and check it against the size of the reverse osmosis system you are interested in.

You can also ask a professional to come in and make the measurements to ensure easy installation.

Amount of Water

Another critical factor to consider is how much water your reverse osmosis system can filter and store. Standard-sized systems can handle 50 to 100 gallons of water a day.

So, if you have a relatively small house with low water consumption, then a 50-gallon system will work fine for you.

On the other hand, if you have a family or relatively larger household, getting a larger-sized rivers osmosis system with a higher capacity storage tank is a smarter option.


Another thing you need to consider when selecting a reverse osmosis system is to assess the state of water you’re getting.

For example, if you get municipal-treated water in your home, you may not need a six-stage filter. A three or four-stage filter will do a great job cleaning your water.

Ease of Installation

While you can do a DIY reverse osmosis installation job watching a YouTube tutorial, it is best to leave it to the experts. However, calling a professional to install will cost you extra bucks.

Fortunately, many companies do offer initial complimentary installation with the purchase. So, check for free installation or special discounts before you make the final purchase.

Waste Created

Reverse osmosis is a cross filtration system that creates a lot of water waste while delivering clean water. In fact, most systems only deliver about 5 to 15% of treated water. This adversely impacts the environment and can also result in higher water bills.

While newer reverse osmosis systems are being designed to reduce the amount of water waste, there are currently no 100% zero waste systems.

So, if you are okay wasting some water to get clean water, then this is something you can go for. However, if you want to live a zero waste and eco-friendly lifestyle, this may be a huge disadvantage for you.


Installing a reverse osmosis system in your home is an investment, so you need to consider the product’s lifespan. You need to ensure you are getting a good-quality product that you can count on for years to come.

So, check for warranties and maintenance plans before purchasing the product. Make sure you check customer reviews to find the best-selling product.

How Does Reverse Osmosis Remove Chlorine? 

FAQs | How Does Reverse Osmosis Remove Chlorine? 

Is reverse osmosis the best filtration?

Reverse osmosis is one of the most effective filtration systems but not the best. Some contaminants may slip through the treated water in trace amounts.

How much does a whole home reverse osmosis system cost?

The cost of a reverse osmosis system for a home depends upon multiple factors such as size, filtration stages, and brand name. However, you can expect to pay around $10,000 to $15,000 for an installed system with a 1500 gallons capacity.

Which filtration system is best for drinking water?

A mid-range reverse osmosis system removes 99% chlorine and other contaminants. You can install the unit in your kitchen under the sink or on the counter to get clean drinking water.

Wrapping Up | How Does Reverse Osmosis Remove Chlorine? 

The majority of U.S. households get a treated water supply. This is both a good thing and a bad thing. Why?

Well, as you may already know, treated water includes chlorine. While chlorination is an excellent disinfecting technique, it gives the water a foul odor and taste. Plus, chlorine can also have many harmful side effects.

Therefore, many people opt for in-home water filtration units such as reverse osmosis systems to remove chlorine from water. 

Reverse osmosis has been a buzzword in the water treatment market. Even though it has a few drawbacks, the no electricity requirements and high efficiency make it one of the most popular water purification systems.

Make sure you invest in a product that suits your needs and delivers optimal results!


This is my blog about the ways and solutions that can help you improve your health by taking more value from drinking water. As improving health means a lot to me, I decided to create the Water On Top project with the purpose to reveal the benefits of water, the finest products to take our daily water to another level, and much more great stuff about water that I believe is on top of our nutrition.

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