Best Under-Sink Water Filters for 2022

We have made this list of the best under-sink water filters to help you choose the best for your and your loved ones’ health.

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Concerns regarding our health and hygiene keep increasing every day, and amid these, having a reliable source of water — the most vital substance for life — is extremely necessary. For many people, tap water is not good enough to be drinkable, and rightly so, as tap water may cause many illnesses, especially in babies and immunocompromised people. However, opting for filtered water prevents many water-related illnesses.

These days, some of the most advanced sink water filter systems are readily available in the market. They are designed to provide you the best water purification without any hassle. However, not every under-sink filtration system is on par with today’s standards. In fact, many of the water filter systems available in the market are substandard and may not properly carry out the purification.

Such being the case, we have made this list of the best under-sink water filters to help you choose the best for your and your loved ones’ health. The sink water filtration systems on our list are selected based on their efficacy — including how well they filter out contaminants, heavy metals, and other harmful substances from the drinking water — to give you the best overall purification.

List of Top 5 Under-Sink Water Filters Systems Of 2022

  1. Waterdrop – Overall Best Under-Sink Water Filters
  2. Aquasana – Most Economic and Eco-Friendly Water Filters
  3. Frizzlife – Best Sellers of Contaminant-Free Water Systems
  4. CuZn – UC-200 Filtration System
  5. Clearly Filtered – 3-Stage Water Filter System

#1. Waterdrop – Overall Best Under-Sink Water Filters 


Product Overview

Beginning our list with a water filter system that has an endless list of features on top of a futuristic design is the Waterdrop 3-Stage Ultra-filtration System. The brand is known for its large variety of water filters, with its under-sink filters range topping the list among them.

This water filter system is particularly known for its combination of innovative features with a one-size-fits-all approach to water purification processes. It comes with three RO filters, making sure any and all kinds of contaminants are thoroughly cleansed out of the water.

The tankless design ensures the filtration system itself does not get clogged with bacteria or other harmful substances after being used for a length of time. It comes with various other features to make your daily water purification a fully automated process, with barely any manual tasks required.

The additional features include automatic flushing featuring a Holiday Mode (automatically flushes the water if not dispensed within 24 hours to keep it fresh), a TDS display to inform you whenever the RO filters need replacement, and various other smart features to make your life easy.


  • Multi-stage filtration process: The water purification is quite thorough when you are using the Waterdrop Ultra-filtration System. It is divided into three stages, the first of which ensures all of the impurities like sand, dirt, and other such particles are removed.

The second stage of the process digs even deeper for impurities and removes minute particles along with bacteria and other microorganisms. This is also when its carbon block filter enriches the water’s taste using the coconut shell build of the filter.

The last stage of the filtration process ensures there are no metalloids, pesticides, or herbicides present in the water when it gets through the third filter. Some of the most harmful heavy metals, lead, and chlorine are also cleaned out during this stage. Afterwards, you get fresh and pure water.

  • Extremely convenient: The Waterdrop Ultra-filtration System is made to be very easy to use. But, the ease-of-use is not only apparent from the hassle-free daily use, as it is also very simple to install. The DIY installation process is very easy and only takes half an hour at most.

Moreover, replacing the RO filters is even easier and can be done within seconds. The replacement process requires no tools and can be done without taking the filter out.

  • Faster water flow: If you are used to the reduced water flow of traditional under-sink filters, that changes now. This water filter comes with a smart faucet which is designed to give you enhanced water flow that is 8x faster.
  • Smart features: Apart from the Holiday Mode and TDS monitoring mentioned above, this under-sink water filter comes with a range of other smart features. The most notable of these is the auto filter cleaning feature, which prevents accumulation of impurities in the RO filters.

Its machine overwork reminder comes in handy when the filtration continues for more than half an hour, which requires giving it a three-minute break. Moreover, if the pump is started and stopped too many times in a short time, the filter system will give a buzzer warning and turn the filtering and power indicators off.

  • Compact design: Among all of the under-sink water filters we evaluated, the Waterdrop Ultra-filtration System has one of the most compact and tactful designs to offer. It takes half of the space under your sink compared to traditional under-sink filters, and the tankless design ensures a greater quality of drinkable water by preventing bacteria formation.
  • Free shipping: Since price was one of the aspects of our research, we made sure the top product comes with as many savings as possible. Apart from a possible discount, you definitely get free shipping all over the U.S. on your purchase of Waterdrop Ultra-filtration System.
  • 30-day money-back guarantee: Not only the free shipping, but customers also enjoy a refund guarantee on their purchase which lasts up to a month. So, even on the off chance you do not find your product satisfactory, your money will not go anywhere.


  • Deep water purification
  • Multi-stage filtration process
  • Eliminates impurities
  • Enhances taste, odor, and color of the water
  • Tankless and compact
  • Space-saving
  • Easy DIY installation
  • Smart monitoring technology
  • Auto flush function to ensure the freshest water every time
  • Designer faucet to increase water flow
  • Free shipping
  • Refund coverage of up to a month
  • Secure checkout


  • Overall cost is a bit higher
  • Replacing the three Reverse Osmosis filters can be costly

Consumer Feedback

There are plenty of reviews for the Waterdrop Ultra-filtration System easily available on the official site as well as other places on the internet. The majority of these indicate exceptional customer satisfaction. The close-packed design, easy installation, smart features, and hassle-free usage are the most-liked things about this product.

=> Click here to visit the official website of Waterdrop 

#2. Aquasana – Most Economic and Eco-Friendly Water Filters


Product Overview

Another 3-stage water filter system known for its wide range of contaminant removal and easy access to highly purified water is the Aquasana Water Filter System. Manufactured by an award-winning company, it is one of the brand’s most popular products.

Aquasana is known for its expertly-designed water filtration systems. Its 3-Stage Undersink Water Filter System is the best example of the brand’s effectiveness in getting you pure water. The filter is made to ensure maximum contaminant removal while providing customers the utmost ease-of-use.

There are plenty of features that make the water filter a top-tier under-sink purifier. It has a reputation for effective contaminant removal, providing you fresh water free of any chemicals, a dedicated faucet to enhance the water flow, and many other highlights, making it worth your hard-earned money.


  • Max contaminant removal: Aquasana Water Filter System is one of the leading under-sink filters when it comes to contaminant removal. The system gets rid of more than 99% contaminants in the water using its cutting-edge filtration technology.

The registered filtration process, known as Claryum filtration, is super enhanced and yields 15x better results compared to a pitcher filter. With effective carbon filters covering more than 77 known water contaminants, this kind of efficiency is nowhere else to be found.

  • No additives: The Aquasana Water Filter System uses industry-grade filters, which are very effective in filtering contaminants. So, you do not have to worry about anything being added to the water in order to achieve the kind of purification it does. The whole process is chemical-free.
  • Tested and certified: The high-efficiency water purification and additive-free process of Aquasana is not all hollow claims. Its under-sink water filter has been tested for the NSF 42, 53, and 401 standard requirements and certified for it as well.
  • Pocket-friendly price: The Aquasana 3-Stage Undersink filter is one of the most affordable options in the market. As of writing this, there is a 50% discount on the filter, but even if you purchase it at MSRP, the price is not bad by any standards.

You can also avail of additional benefits on your purchase through the Water For Life Price plan, which lets you enjoy perks like discounts on filter replacements, free shipping, and extended warranty coverage.

  • Dedicated faucet: Although it is rare with filters in this price range, the Aquasana Water Filter comes with a dedicated faucet. Buyers have the option to choose between any of its three all-metal designer faucets to come along with the system.

The faucet is designed in a way that improves the flow of your filtered water. This way, you will not have to wait longer for the cup to fill up.

  • Easy filter replacement: As we mentioned earlier, one of the most important factors for choosing a water filtration system is the ease-of-use it provides. Aquasana 3-Stage Undersink Filter is extraordinary in that regard. The filter replacement is as easy as it gets. All you need to do is twist and replace the filter without having to disconnect any hoses and water lines.


  • Removes up to 77 common water contaminants
  • Activated carbon filter gets rid of drugs, herbicides, pesticides, and other harmful chemical elements
  • Retains minerals
  • No additives used during water filtration
  • Easily replaceable filters
  • Certified by NSF and ANSI standards
  • Affordable price
  • Comes with a dedicated faucet
  • Environment-friendly build


  • Not very compact in size
  • Filters only last six months
  • Due to the eco-friendly build, replacement parts are hard to find

Consumer Feedback

The official site for Aquasana Undersink System has an overwhelming 15,000+ reviews on display. Customers find the filter far exceeding their expectations when it comes to efficiently purifying water. Apart from the efficiency, people also like the affordability of the system. However, some also complained of the short duration of its filters and non-availability of replacement parts.

=> Click here to visit the official website of Aquasana

#3. Frizzlife – Best Sellers Of Contaminant-Free Water Systems 


Product Overview

Frizzlife takes the cake when it comes to manufacturing the best-value water solutions. Its under-sink water filter system is one of the most affordable yet effective water purification systems out there. But, the cost-effective pricing is not by any means achieved through compromise on quality. The filter is highly efficient and gets the job done exceedingly well.

With features like auto shut off valve, 0.5 micron filtration technology, dual water-line compatibility, and an overall environmentally-friendly usage, the under-sink water filter is the go-to filtration system for thousands of users. It is currently the best budget under-sink water filter available on the market.


  • Best bang for your buck: The Frizzlife Water Filter System is among the least expensive in the entire industry despite its superior quality. In spite of having a 0.5 micron carbon-block filter, the unit costs almost half the average price of an under-sink water filter system.

Moreover, its filter replacement is just as cheap. Overall, the unit provides you one of the cheapest possible water accesses while also providing the highest purification and mineral-retention.

  • Removes 99.99% of contaminants: Although the filtration is a 2-stage process with the Frizzlife Under-Sink system, it is just as efficient in removing contaminants and impurities from the water. In fact, the filter gets rid of 99.99% of the common contaminants, so the water you get is spring-fresh in both taste and odor.
  • Simple installation method: The installation process for the Frizzlife 2-Stage Water Filter System is extremely simple and one of the fastest. Its auto shut down valve makes installing the unit a breeze. You will not have to worry about waterline compatibility either because it is compatible with both ½ inch and ⅜ inch lines.
  • Does not need a dedicated faucet: The filter systems on our list so far have been ones with a dedicated faucet, but the Frizzlife 2-Stage Water Filter System is plug-and-play from every aspect. You do not need a dedicated faucet for it, as you just have to connect it to the main sink faucet and it will be ready to go.
  • Eco-friendly: Apart from the unbelievable money-saving and higher performance, this water filter unit is also up there when it comes to being environmentally-friendly. It is designed to use as little plastic as possible, and its filter replacements are also plastic-free.
  • Satisfaction guarantee: Although it is rare for any good water filter system to be priced so low, it is even rarer for it to be covered with a money-back guarantee. But, the Frizzlife 2-Stage Water Filter System comes with a satisfaction guarantee, which means you get a full refund within a month if you do not like the product.


  • Filters 99.99% of contaminants
  • Fast installation
  • Cheap and easy filter replacement
  • Best value for money in its price range
  • Environmentally-friendly
  • Faster water flow
  • Saves space and can be used with any faucet
  • 30-day money-back guarantee


  • Filter life is shorter
  • Not compatible with every faucet
  • Compatibility with some water lines is not as good as the others, so water pressure might drop with those

Consumer Feedback

Despite being one of the cheapest available options for water filters, the Frizzlife 2-Stage Water Filter System provides great filtration even when compared to the most advanced systems. For this reason, it is a favorite for many people looking for affordable water purification. It has an overall 9.4 score from consumers, which is indicative of top-notch performance.

=> Click here to visit the official website of Frizzlife

#4. CuZn – UC-200 Filtration System


Product Overview

Before we get into the nitty gritty of this filter system, you should know this water filter is designed to only purify municipal water. The system is also not handled to filter hard water. Neither of these should not be an issue for people living in urban areas, but if you are using well water in your home, this system is not suitable for you.

The CuZn UC-200 uses a 3-stage purification process to remove organic and inorganic impurities from your water supply while also retaining the essential minerals. The whole system is designed to be extremely easy to install and setup, and it usually takes five minutes to hook up without the need for drilling or extra mounting required.

According to the company, you can expect the system to last for years, as it is designed to filter over 50,000 gallons of water. Afterwards, swapping the filter with a new one is extremely easy. Let us look at the individual features of this system.


  • Made to be long lasting: This system is designed to go for years without needing a filter replacement. Unlike other systems that require a filter replacement within a few months, CuZn UC-200’s filters are made to last up to five years in typical household settings.

The company is so confident in the quality and performance of its filters that it backs them up with a five-year performance warranty. In case your unit’s filter gives up before that time, the company will issue a replacement for free.

  • Extremely easy to install: A lot of water filtration systems can be very hard to install, needing parts to be drilled and mounted. But, you do not need to worry about any of that with this system. Most user reviews reported that it takes as little as five minutes to get this system up and running. In most cases, all you need is an adjustable wrench to install it.

Do not worry if you have a non-standard plumbing connection. Just contact the company, and they will send you the necessary parts and an alternate install kit for free.

  • 3-step filtration system: This water filter uses a state-of-the-art filtration consisting of micro sediment membranes, KDF-55, and coconut shell carbon filtration. Thanks to these steps, the system is able to remove a large number of organic and inorganic impurities, including, but definitely not limited to, herbicides, pesticides, chlorine, heavy metals, bad taste, algae, molds, odors, and much more.

Despite taking out all of the harmful impurities, the filtration allows beneficial minerals, like calcium and magnesium, to remain in the water. A lot of reviewers actually commented on how the unique filtration system actually made the water taste better.

  • Bacteriostatic: Mold and bacteria growth inside the filter is a huge problem with a lot of filtration systems, which defeats the whole point of it. Luckily, the CuZn UC-200 filtration system is completely bacteriostatic, which means it will not let any bacteria, mold, or algae grow within the filter.
  • Very affordable: At the time of writing this, the CuZn UC-200 costs $120, and the price goes even lower during sales. This is an absolute steal for a filtration system that comes with a five-year (or 50,000 gallons) warranty and a 90-day satisfaction guarantee.
  • Extremely responsive customer support: A lot of users indicated that the company’s support is very responsive and helpful. In case of any installation issues, need for custom parts, or replacement filters, they reply very quickly and any parts are issued free of cost.
  • 90-day satisfaction guarantee: CuZn has covered the filtration system with a 90-day satisfaction guarantee. In case you are unsatisfied with the product, just contact their customer support and initiate a return within that period. Then, you will get your money back.


  • Extremely long lasting
  • In case of system failure within five years, the company will issue you a replacement for free
  • Very easy to install
  • One of the most affordable filtration systems on the market
  • Free custom installation kit if needed
  • Gets rid of harmful contaminants and bad tastes while also retaining necessary minerals
  • Bacteriostatic filter ensures no growth of mold or bacteria in the system
  • Made in the U.S.
  • 90-day satisfaction guarantee
  • Company’s support is very responsive and helpful


  • Not suitable for private/well water
  • Does not soften or filter hard water
  • Does not reduce TDS or PPM readings
  • No option for filter replacement. After five years or 50,000 gallons (whichever comes first), you will have to replace the whole system

Consumer Feedback

Customers love how easy this system is to install, as in most cases, only an adjustable wrench is needed. A lot of people also commented that the filtration system made their tap water taste better. Of course, your mileage may vary on that front. Lastly, people loved CuZn’s customer support. They provide a toll-free number as well as an email in case you face any issues with its products. Also, any additional parts are sent out to customers free of cost.

=> Click here to visit the official website of CuZn

#5. Clearly Filtered – Most Affordable Under-Sink Water Filtration System 


Product Overview

Clearly Filtered claims its 3-stage water filter system is the best in the market and provides the same quality of water that customers have come to expect from Clearly Filtered’s water bottles.

According to the company, this filtration system removes up to 99.9% of the harmful contaminants from your tap water. The performance is so impressive that the company claims this system removes more chemicals and contaminants from your water than the top five filtering systems combined.

The filtration system is very easy to install and is made with those people in mind who are renting their house. It is a non-permanent installation that only requires a wrench and a screwdriver. The process is extremely simple and can be done by anyone without professional help.


  • One of the best water filters in the market: Clearly Filtered is a very reputable and established brand in the market known for their quality products, and this 3-stage filtration system is no exception. According to the company, the product outperforms the other top five leading brands combined.

The filter has been extensively tested to NSF and EPA standards, and it removes up to 99.9% of fluoride, lead, pesticides, insecticides, PFOA/PFAS, and other harmful chemicals/contaminants from the water while keeping the nutrients intact. All in all, this system filters out over 232 harmful contaminants.

  • Long lasting filters: The filters in this system last for up to 20,000 gallons. How long a filter lasts depends on the number of people living in your household. Large families usually need to replace the filter in around 9 months, whereas small families can usually go between 12-15 months without needing a filter change.

The filter replacement process for this system is completely tool-free. All you need to do is twist off the filter by hand and remove it, then screw in the new filter. It is as easy as that.

  • Slim and space-saving design: A lot of filtration systems are cumbersome and might not fit in the space you have beside/underneath your sink. You do not have to worry about that with Clearly Filtered’s offering, as it is one of the most compact designs we have seen in the market.
  • Great customer support: The company’s customer support is known to be extremely helpful and responsive. It is not very often that people have problems with their products, but when they do, the customer support is very helpful and quick to respond.
  • Lifetime guarantee: This is the only system you will ever need to purchase. Clearly Filtered is one of the few companies offering a lifetime guarantee for their products. If this system ever breaks down, they will replace it for no cost, no questions asked.


  • One of the best performing water filters on the market
  • Removes 232+ contaminants from your water
  • Improves the taste of your tap water
  • Extensively tested to NSF and EPA standards
  • Long lasting filters
  • Filter replacement is completely tool-free with twist off, twist on design
  • Non-permanent installation designed with renters in mind
  • Slim design that does not require much space
  • Great customer support
  • Lifetime replacement guarantee


  • Expensive
  • Replacement filters are also quite costly
  • Some people reported that this system reduced the water pressure

Consumer Feedback

People who bought this filtration system loved it for its great performance. A lot of people reported it improves the taste of their tap water. Customers also love how easy it is to install, and you can even install it in a rented house, as the installation is non-permanent. Additionally, filter replacement is also a cinch.

Lastly, the lifetime guarantee makes this product a risk-free investment. The company is known for its great customer support and issuing replacements without any questions or issues. If this system ever breaks down, you get a replacement one for free.

=> Click here to visit the official website of Clearly Filtered

How We Chose the Filters for Our List

There are many aspects involved in differentiating between a good water filter system and a bad one. Keeping that in mind, we carried out a detailed analysis on the newest and most feature-rich under-sink water filters to find the best of the best. Below are the two primary aspects of our research.


The primary task of any good filtration system is to remove the greatest amount of impurities from water and to make it rich in taste and color. The same is the case with good under-sink water filters, so the first factor for our selection-making was efficacy.

All of the products on this list outperform even the best when it comes to removing contaminants, heavy metals, and microorganisms from water. Moreover, they get rid of any bad taste and disagreeable odor from the filter water to enhance its flavor as well.

User Convenience

We need water on a daily basis, and having to deal with a number of difficulties every day when using a water filtration system can be a nuisance. But, there are a good deal of water filter systems available now that make the process simple and easy.

We made sure the ones that made it to our list excelled in user convenience. Not only should they make the daily usage easy, but the installation and filter replacement process of the under-sink water purification systems on this list is extremely simple and fast.

Why Should You Use Water Filters?

That is a question that gets asked very often. After all, many people are perfectly satisfied with the tap water they get. Let us cover a few reasons why you would need one.

Removes harmful contaminants while retaining healthy minerals

According to a study done in 2016, tens of millions of Americans are exposed to unsafe levels of industrial chemicals through their tap water, even in urban areas which get municipal water. Water filtration systems remove these chemicals and other harmful contaminants so you do not get health issues later down the cold water line.

Improved taste

Some contaminants might not be harmful for health, but they do alter the taste of your water. That is why a lot of people report that when they install a water filtration system, the taste of their tap water improves significantly.

Cost savings 

If you currently buy bottled water, a water filtration system can save you hundreds of dollars per year. In case you just use tap water, contaminated tap water can cause serious health issues down the line, which could be expensive. In either case, the cost of a water filtration system is significantly cheaper.

Factors to Look for in an Under-Sink Filter System

With so many products in the market, what factors should you keep in mind when purchasing a water filtration system? Let us briefly cover these.

  1. Type of filter: When it comes to a filter, there are multiple variables you should consider. First, buy a system whose filter has been extensively tested and certified according to industry standards. Second, consider longevity. Some under-sink filters last only a few months, whereas others can last for years. Third, consider the cost of replacing the filter or whether the filter is even replaceable.
  2. Dimensions: Before you fork over hundreds of dollars for a filtration system, consider the space you have beside/under your sink. Some filtration systems can be very cumbersome, and you might not have the space to install them.
  3. Installation procedure and cost: Some filtration systems are made to be extremely easy to install, and you can install them on your own. Others will require you to call a plumber, which will incur extra costs. Another thing to consider here is whether the system has permanent/semi-permanent installation. If you are currently living in a rented house, you will have to go for a system that offers non-permanent installation.
  4. Maintenance cost: Filtration systems are not maintenance free. In most cases, you will need to call a plumber to take care of the maintenance. Even if you learn to DIY, you still have to consider the time costs. When buying a system, find out how often it needs maintenance.

FAQs: Under-Sink Water Filter System

1. Can I test my current tap water to see if it contains any contaminants?

Yes, there are two solutions for testing the water. The first is water testing kits, which are mainly suitable for well water but can be used for municipal water as well. The second is to contact your water supplier and ask them for information on the source of their water and what filtration methods they use.

2. Do water filters also soften the water?

No. Water filters are not the same as water softeners. A water softener removes mineral elements like calcium and magnesium, whereas water filters remove harmful contaminants like bacteria, mold, heavy metals, and sediments.

3. Do I need to call a plumber to install the water filter system?

The answer to that question depends on the type of system you buy. Some systems are designed to be extremely easy to install, while others require you to get professional help from a plumber. Before you buy a filtration system, consider its installation procedure.

4. Is a reverse osmosis system better than a water filtration system?

The simple answer is yes. While it is true that RO systems remove more contaminants from the water, it is a bit more complicated than that. For one, reverse osmosis systems cost a lot more than your typical water filtration system. Even after the initial purchase cost, they waste a lot of water. Lastly, they require more maintenance in general. The last two factors mean that not only are they expensive to purchase, but they are more expensive to keep.

5. Do water filtration systems need electricity to run?

No, these systems do not need any electricity.

6. Is hard water bad for health?

In case you are getting hard water through your tap, you might be wondering if it is a good idea to get a water softener as well. The answer is that hard water is generally safe to drink. In fact, it might actually provide your body with extra nutrients due to its higher calcium and magnesium content. According to preliminary research, drinking hard water has been linked to better cardiovascular health.

On the other hand, it can cause problems if you use it for showering. For example, it can reduce moisture on your skin and in your hair, causing dandruff and eczema.


The quality of water we drink can drastically affect our health and lifestyle. A lot of studies have started pointing out that millions of Americans, even in urban settings, are being exposed to toxic chemicals through their tap water. As a result, a water filtration system has become a necessity.

With so many water filtration systems in the market, and every one claiming to be “the best,” it can be hard to find the perfect product for your needs. It is that problem we tried to address today, as we brought you the absolute best water filter systems. We hope this review helped you make an informed choice.

Best Under-Sink Water Filters for 2022