The 10 Best Under-Sink Water Filters for Clean H2O

Updated: Nov. 03, 2023

This collection of the best under-sink water filters will have you and your family enjoying clean, clear and contaminant-free water in no time.

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5 Best Under Sink Water Filters For Clean H2oVIA MERCHANT

Instead of consuming countless single-use plastic bottles or constantly refilling a pitcher filter, an under-sink water filter is a convenient alternative. These systems are hidden in the cabinet below your sink and connect to your existing water supply hose, allowing you to enjoy clear, contaminant-free water right out of your faucet.

“Under-sink water filters are a popular way to get healthier, better-tasting water because they typically remove more contaminants than pitcher filters and even bottled water,” says Derek Mellencamp, the General Manager at Aquasana and a leading national water filtration expert. “By connecting directly to the water source at its point of use (e.g., the kitchen sink), under-sink filters use your home’s water pressure to force tap water through ultra-dense filtration media, giving it the force and speed to remove more contaminants, faster, than a gravity-based system like a pitcher filter.”

1 / 10

Best Overall Under-Sink Water Filter

Aquasana Two-Stage Under-Sink Water Filtration System

This Aquasana filter uses two types of carbon filters and an ion exchange system to remove up to 99% of contaminants, allowing beneficial minerals to pass through. It’s an easy choice for the best under-sink water filter and efficient enough to process half a gallon of water every minute, costing just $0.10 per gallon.

The filters are simple to replace and their compact size makes this filter convenient to fit inside a wide range of kitchen cabinet sizes.

Pros

  • Removes up to 99% of 77 contaminants
  • Includes kitchen faucet
  • Easy to install
  • Comes in multiple finishes
  • Certified to National Science Foundation (NSF) Standards 42, 53, 401 and P473

Cons

  • Filters require replacement every six months

2 / 10

Best Budget Under-Sink Water Filter

Culligan EZ-Change Under-Sink Filtration System

This Culligan model provides effective filtration at a price much lower than similar under-sink options. For a wallet-friendly price, you get an RC-EZ-1 cartridge that’s effective enough to prevent Class III particulates from infiltrating your drinking water, improving the overall taste.

This cartridge has a lifespan of up to 3,000 gallons and is compatible with a range of Culligan replacement cartridges, from EZ-1 to EZ-4. We also love the dedicated dispenser faucet, which, depending on your sink setup, can fit over an existing sprayer or soap dispenser hole.

Pros

  • Affordable price
  • Filter lasts up to 12 months or 3,000 gallons
  • Includes all installation hardware
  • Meets American National Standards Institute (ANSI) Standard 42 certification

Cons

  • Relatively low flow rate of .5 GPM

3 / 10

Best Reverse Osmosis Under-Sink Water Filter

Apec Water Systems ROES-50

This Apec system utilizes five stages of filtration, including a reverse osmosis membrane and dual coconut carbon blocks, to remove up to 99% of all contaminants in your drinking water. It also includes a brushed nickel faucet, making it a smart option for homeowners wanting to replace an outdated model.

Apec does an excellent job of setting you up for success when it comes to installation, too and includes two housing wrenches for the filter and membrane components, as well as a link to step-by-step instructional videos.

Pros

  • Multi-stage filtration
  • Easy to install
  • 2-year warranty
  • Improves water taste
  • Removes up to 99% of impurities

Cons

  • Uses more water than other filter types

4 / 10

Best Ultrafiltration Under-Sink Water Filter

Waterdrop 15UA-UF Ultra Filtration System

Thanks to a specialized membrane and multiple filtration media, like activated carbon, this Waterdrop system provides a filtration accuracy of 0.01 microns. The direct-connect fittings make installation a breeze, dual gaskets prevent leaks and a converter works on both 1/2- and 3/8-inch water lines.

We’re most impressed by the lifespan of this filter, which has a max service life of two years or 16,000 gallons. The compact size is convenient for tighter spaces, making it a quality RV water filter while still powerful enough to process 0.75 gallons per minute.

Pros

  • Effective against extremely fine contaminants
  • Filter lasts up to two years or 16,000 gallons
  • Retains beneficial minerals
  • Simple installation
  • Affordable

Cons

  • Doesn’t include a dispenser or faucet

5 / 10

Best Tankless Reverse Osmosis Under-Sink Water Filter

Waterdrop G3P600 Reverse Osmosis System

Unlike most reverse osmosis systems that require a separate pressure tank to store filtered water for drinking, this tankless Waterdrop model uses an electric pump to provide water as needed. This allows you to experience the benefits of reverse osmosis without needing a lot of extra space.

However, it does require an accessible electrical outlet. You’re also getting a smart display faucet, which gives you a real-time readout of the filter status, as well as the quality of the water you’re drinking.

Pros

  • Requires 70% less space than tanked systems
  • Sleek design
  • Simple to maintain
  • Three filters included with purchase
  • NSF/ANSI 58 + 372 certified

Cons

  • Expensive
  • Requires an electrical outlet

6 / 10
Clearlyfiltered Three Stage Water Filtration System via merchant

Best Splurge Under-Sink Water Filter

ClearlyFiltered Three-Stage Water Filtration System

The ClearlyFiltered Three-Stage Water Filtration System is a bit pricey, but the easy twist-and-go installation and three-stage filter makes it well worth the upfront cost. Between a space-saving design and a system that gets rid of virtually all chlorine, fluoride, lead and PFAS. Unlike comparable systems, the filters last up to a year and there’s zero power required for the install.

Like a filtered shower head, the ClearlyFiltered system uses multiple stages of filtration, including a coconut carbon pre-filter that minimizes sediment and targets common contaminants that affect taste and smell. An auto-ship option not only guarantees that you’ll always have a new filter on hand when the current one expires, but it also knocks more than $50 off the initial cost of the filter.

Pros

  • Complies with NSF/ANSI standards
  • Extended 2000-gallon filter life
  • No separate or second faucet required
  • Only requires a wrench for install
  • Option to sign up for auto-ship filters

Cons

  • Pricey

7 / 10

Best Under-Sink Water Filter for Well Water

iSpring Six-Stage Reverse Osmosis Filtration System

The best well water filtration systems remove tap water contaminants, such as sediment particles, minerals, chemicals and bacteria. iSpring’s Six-Stage Reverse Osmosis Filtration System uses USA-made filters to eliminate over 1,000 contaminants. This includes lead, chlorine, fluoride, arsenic, asbestos, calcium and sodium.

Offering a 1:1 pure to waste water ratio, this fast-slow system installs in a few hours and includes an alkaline remineralization filter. The filter restores healthy minerals and produces a balanced alkalinity, making water taste better and boosting health benefits. An ultra-quiet operation ensures you won’t even remember it’s there—until you taste your water, that is!

Pros

  • 1:1 fast flow ratio
  • Alkaline remineralization restores healthy minerals
  • Made in the USA
  • Do-It-Yourself installation
  • 100-gallon capacity

Cons

  • Installation can take up to 4 hours

8 / 10

Best Customizable Under-Sink Water Filter

Express Water Reverse Osmosis Five-Stage Filtration System

Not all water filters work the same, as evidenced by the number of ways folks filter their water. The Express Water Reverse Osmosis Five-Stage Filtration System takes this into account. Not only is the filtration system fully upgradable and customizable with quick connecting fittings, but the five-stage system filter out everything from dirt and rust to difficult impurities like lead, arsenic and chromium.

Finally, a fifth filter pass ensures every glass contains zero taste and odor, meaning it’s ideal for ice trays and pet dishes. We recommend using water test strips when setting up the system—this will determine which custom attachments will be most effective. Additional attachments include UV, alkaline and deionization filters.

Pros

  • Customizable filters tailor the system to water quality
  • Emergency leak stop detector
  • Adheres to NSF/ANSI drinking water standards
  • Air injection pressure tested
  • Easy installation with  labeled color match system

Cons

9 / 10

via merchant

AO Smith Two-Stage Under Sink Carbon Filter

As compact as it is effective, the AO Smith Two-Stage Under Sink Carbon Filter is the perfect system for camping. The dedicated faucet and filter system installs in minutes thanks to the included tee and tubing—no plumber required. At just over five inches tall, it’s easily one of the most compact units on this list, making it ideal for use in small spaces like RVs and campers.

Pros

  • Only five inches tall
  • Faucet included
  • Plumber-free installation
  • Filter lasts for six months
  • WQA tested and certified to NSF performance standards

Cons

  • Best for families of up to four
  • System will not reduce TDS

10 / 10

Best High-Capacity Under-Sink Water Filter

CuZn Under Counter Water Filter

For large families or those who tend to forget to change out filters, a high-capacity filter is a must. The CuZn Under Counter Water Filter lasts up to five years per filter, meaning fewer replacements. A coconut shell carbon and micro sediment membrane ensures there’s fewer of the following contaminants: chlorine, disinfection by-products, herbicides, pesticides, sediment, water soluble cation heavy metals (lead, mercury, chromium VI, cadmium, etc), bad taste and odors.

In addition, it has a small enough profile that there’s still plenty of space to install an under-sink water heater next to it.

Pros

  • Lasts up to five years per filter
  • Made in the USA
  • Doesn’t affect water pressure
  • Simple to install
  • Removes contaminants that affect taste and odor

Cons

  • Does not soften water or remove TDS
  • For use with municipal water sources, not well water

What to Consider When Buying an Under-Sink Water Filter

“When looking for any type of filter, we always recommend starting by checking your local water quality report to find out which, if any, contaminants may be present in your area. As part of the EPA’s Safe Drinking Water Act, all U.S. water suppliers are required to send out an annual report that tells you where your water comes from and what’s in it,” says Mellencamp. “Next, always look for a filtration system that has been independently tested and certified to NSF/ANSI or IAPMO standards to address the contaminants you’re concerned about.”

In order to select the best under-sink water filter for you, consider the different types of filtration available. There are many variations of water filters. Basic carbon options work by binding to contaminants as the water flows through. Reverse osmosis units force water through a semipermeable membrane that captures even smaller compounds and impurities.

If you have a large family or use a lot of water for cooking and drinking, make sure you take the flow rate into account as well. This metric should clearly state gallons per minute (GPM). You should also ensure the unit you’re considering will fit under your sink. Also, if you plan to install it yourself, make sure it doesn’t require any DIY methods that are outside your expertise.

How We Found the Best Under-Sink Water Filters

At Family Handymanwe’re always looking to help homeowners and DIYers make the right purchase for their specific needs. We analyzed over 20 top-selling under sink water filters before narrowing our list down to the 15 filters with the best ratings. From there, we combed through hundreds of reviews, looking for real accounts of how each filter performed for DIYers both experienced and inexperiencedThis rigorous research led us to the final filters, with those top 10 making our official list.

FAQ

Are under-sink water filters worth it?

“We conduct a national consumer survey each year and our recent fifth annual Water Quality Survey found that concern over drinking water quality in the U.S. has more than doubled over the past two years with seven in 10 Americans expressing worry about the quality of their drinking water at home,” says Mellencamp. “Now, 91% of Americans filter their drinking water at home. It’s no wonder, considering an estimated 45% of the nation’s tap water contains the ‘forever chemicals’ known as PFAS and the EPA recently reported that almost a tenth of the nation’s drinking water service lines contain lead.”

If you consume more than a few gallons of tap water a day and you can afford one, an under-sink water filter is probably worth it. “Instead of having to constantly refill a pitcher and wait for water to drip through, under sink filters allow you to instantly enjoy clean water straight from the tap without waiting or taking up valuable counter or fridge space,” notes Mellencamp.

Once installed, they do most of the work and, until it’s time to replace the filter, are generally low-maintenance. On the other hand, if you don’t drink that much water or if you’re a renter, a pitcher or faucet-mounted filter could be a more practical option.

How long do under-sink water filters last?

The lifespan of an under-sink water filter cartridge can vary from six months to multiple years. The lifetime depends on the size of the unit, as well as the quantity of water processed. “Filtration elements need to be replaced at some regular frequency, usually every six months,” notes Mellencamp. “If the filters are not replaced and contaminants accumulate in the system, the water gets blocked over time. This creates two issues with water filters: 1) the water flow can slow and 2) the water pressure in the system can increase which puts stress on the system and can cause it to fail faster.”

How do you change an under-sink water filter?

The best under-sink water filters make changing out their filters and cartridges a straightforward process. However, some are easier than others. “You can typically rotate the filters out of the unit and pull them out. Then you install the new filters by rotating them into the filter. Many systems have automatic shutoff valves that turn the water off as you rotate,” says Mellencamp. However, not all do. Some multi-stage units may require you to shut off the water supply and use a housing wrench to access the spent cartridge.

Why You Should Trust Us

I’m a freelance writer who specializes in the home improvement, DIY and appliance space. Having spent more than five years as a residential and commercial carpenter in NYC–specializing in custom furniture construction and installation–I use my hands-on experience and expert insight to craft product reviews, buying guides and how-to articles. I’ve previously written for CNN Underscored, Business Insider and Popular Mechanics, in addition to Family Handyman.

Emily Way is an associate shopping editor for Family Handyman with experience researching products and recommending the best designs to consumers. She researched and updated this piece. Way consulted Derek Mellencamp, the General Manager at Aquasana and a leading national water filtration expert. Derek Mellencamp joined Aquasana in April of 2010 and is responsible for leading the Aquasana marketing efforts from product management to branding.