The Best Under Sink Water Filter – Complete Buying Guide & Reviews

Clean, safe, great-tasting water is essential to any home. With the best under sink water filter available, you can insure your home with great water for life.

One of the best ways to make the most of your tap water is by using an under sink water filter. Water filters eliminate the need for bottled water, which is a huge waste of money and plastic. Under the sink, filters are a great alternative to counter top filter systems or filtering pitchers because they don't waste any valuable counter or fridge space.

Under sink water filters are now more effective and efficient than ever. Until recently, some contaminants were only able to be removed with reverse osmosis systems that were expensive and wasteful. New technology in the cartridge filters used by under-sink water purifiers allows them to reduce more contaminants than previously possible. 

With the new efficiency in these products, choosing the best under sink water filter is still a daunting task. No need to fear! We've compiled a list of the best under sink water filter options for you and your home. Let's take a look.

Quick Overview: Our Best Under Sink Water Filter Choices

Last update on 2022-05-16 / Affiliate links / Images from Amazon Product Advertising API

CuZn UC-200 Under Counter Water Filter - 50K Ultra High Capacity

Last update on 2022-01-03 / Affiliate links / Images from Amazon Product Advertising API

The CuZn UC-200 Under Counter Water Filter is one of the most popular under sink filtration systems on the market, and it’s pretty easy to see why. The benefits of this option kick in before you ever use it to filter your water because it's one of the easiest products to install--it only takes about 5 minutes.

Unlike most other under sink water filters that use a conventional system (see above), the CuZn UC-200 uses a simple water filter system that doesn’t require an additional faucet or any modifications to your sink or counter. To make installation even easier, CuZn offers free, easy to follow video instructions.

Better yet, once you’ve installed one of these, it will be good to go for years! The CuZn UC-200 has a lifetime capacity of about 50,000 gallons of filtered water, which lasts most households around five years. That’s a definite convenience upgrade from other filters that need to be changed every six months, and your wallet will thank you too.

One thing to note: the CuZn UC-200 is a bit bigger than many other filters, which could be a problem if you don’t have much space under your sink, so make sure to check the dimensions first. Otherwise, everything about this under sink filtration system is great.

Things We Like:

  • Lifetime capacity of 50,000 gallons or 5 years
  • 5-year pro-rated warranty and a 90-day satisfaction guarantee
  • Designed for use with municipal water, not private well water
  • Easy installation: no additional faucet
  • 3 stage filtration process includes Micro Sediment Membranes, KDF-55 & Coconut Shell Carbon

Things We Don't Like:

  • Not meant for private water wells
  • A bit larger than other filtration systems

Best Conventional Under Sink Water Filter:

Aquasana 3-Stage Under Sink Water Filter System with Brushed Nickel Faucet

Last update on 2021-12-08 / Affiliate links / Images from Amazon Product Advertising API

If you want a water filter with a separate faucet, this is an excellent choice. The Aquasana 3-Stage Under Sink Water Filter System is another great choice. It is a high-performance filter that provides great-tasting healthy water.

The next two filters use Claryum filtration technology to remove over 97% of chlorine, lead, asbestos, herbicides, pesticides and over 60 other common water contaminants. The Aquasana also comes with a performance indicating advice that lets you know exactly when you need to change your filters, for added peace of mind.

It isn’t as easy to install as the CuZn UC-200 or other simple under sink filtration systems, but once you’ve completed installation, changing the filters is a breeze. A quick quarter turn will remove the old filter, and then simply twist on the new one.

You don’t need to disconnect any hoses or water lines. The filters also have minimal disposable plastic parts, making the Aquasana a more eco-friendly option.

This filter comes with a great chrome faucet that will make a beautiful addition to any kitchen. If the brushed nickel finish isn’t your style, there are other finish options too!

Things We Like:

  • 1 Lithium Metal batteries required (included)
  • Battery life of 1590 hours
  • One year warranty
  • Removes up to 99% of 77 contaminants including lead, mercury, pesticides, pharmaceuticals, and more
  • No water is wasted, and no contaminants are added back into your water
  • Capacity of 600 gallons ($.09 per gallon)

Things We Don't Like:

  • You'll need to continually buy batteries for this model
  • A bit pricier than others

Woder 10K Ultra High Capacity Direct Connect Water Filtration System — Under Sink, Premium Class

Last update on 2021-11-20 / Affiliate links / Images from Amazon Product Advertising API

If you're looking to spend less than $100 on an under sink water filter, this one is the way to go. Costing less than $70 and lasting up to 3 years, the Woder 10K High Capacity Direct Connect Water Filtration System offers excellent value for the money.

This filter uses unique technology to remove over 99.99% of contaminants while leaving in essential minerals which are vital to your health, including calcium, potassium, sodium, phosphorus, chloride, and magnesium.

Woder filters eliminate lead, heavy metals, chlorine, chromium 6, mercury, volatile organic compounds, carcinogens, and other contaminants in addition to odors and bad tastes.

Not only is it effective, but the Woder 10K is also easy to install and maintain. Everything you need to install it is included, and it requires no expert skills to install in a short time.

After installation, it will last for around three years with no adjustment or maintenance, filtering up to 10,000 gallons in that time. It’s also really compact, making it a great option for small apartments, bathroom sinks, and offices.

Things We Like:

  • Capacity: 10,000 gallons
  • Flow rate: 3 gallons per minute
  • Eliminates 99.9% of contaminants like lead, heavy metals, and chlorine
  • Easy installation: comes as a complete assembled kit
  • Will last for up to 10,000 gallons, or roughly three years of use
  • Money-back guarantee

Things We Don't Like:

  • Needs to be adjusted every three years or so
  • Not as efficient or long lasting as other models

APEC Top Tier 5-Stage

Last update on 2021-11-20 / Affiliate links / Images from Amazon Product Advertising API

If you are out to find a top of the line product without much concern for the budget, the APEC Top Tier has  a significant amount of features that shade all others.

While it is priced double compered to the competition, it has a significantly greater capacity. It is not hard to maintain and the process of reverse osmosis will clean all the impurities from the water without influencing the minerals that should be inside and which give the water the ’’fresh taste’’.

There is a reason why this product is marketed this way, as it gives all the features of prior products, which added quality of the materials, durability, and capacity. There are no actual downside for this product as it is, but the price tag might be over budget for many households, and if you don’t really need all the bells and whistles, you may consider one from above.

Things We Like:

  • Good materials
  • Good design
  • Easy installation
  • Removes 99% of impurities, both organic and non-organic

Things We Don't Like:

  • Doesn't have a lifetime warranty
  • If you're on a budget, you may want to look at other options

Features to Consider

Different Types of Under Sink Water Filters

There are two main kinds of water filters to consider when making a purchase. It's important to know how these work. Let's explore this now.

Simple Under Sink Filter

These water filters are affordable and easy to install. When they are installed under your sink, all the cold water supply passes through the filter before it comes out from your regular faucet.

Once installed, simple under sink water filters are also incredibly easy to use--you don’t even need to remember to use it, your cold water will be automatically filtered whenever you turn on the tap.

In addition to their convenient simplicity, these filters are also relatively cheap, easy to install, and they require no additional faucet or modification to your counters.

But keep in mind that because more water flows through simple under sink water systems, you will need to change the filters more often. All in all, they’re a great option for those looking for an easy and affordable water filter.

Conventional Under Sink Filter

The other common type of under sink water filters are called conventional under sink filters. They've been around much longer than the simple filter systems, but don't count them out as outdated.

 Conventional under sink filters are still an excellent choice for someone looking for a water filter that will send drinking water straight from the tap to glass. They are more complicated to install because they require a separate tap for the filtered water. 

After diverting the water from the main cold water pipe, it passes through the filter and comes out of a separate faucet that’s been mounted to the sink. Only water through that faucet is filtered, leaving your regular faucet unfiltered as normal.

Because less water is filtered through the system, the filters will last much longer. Also, because the reduced flow slows things down, your water will spend more time in passing through the filter, making it even cleaner.

The obvious con to this system is that it can be a pain to install, and you’ll probably have to drill a hole in your counter or sink for the new faucet. Conventional under sink systems are also much slower, so if you plan on filtering a lot of water in a short time or using filtered water for cooking, a simple system is probably better.


Most under sink water filter systems require new filters every six months or so, but there are some that last up to 5 years. This partially depends on the type of system you install: simple under sink water filtration systems can often last for a shorter time because more water passes through them.

Sometimes the longer lasting ones are more expensive, but usually, they're well worth the cost. In addition to reducing replacement filter costs, a filter's longevity may be an indication of its quality.

Because most filter cartridges work in pretty much the same way if one is capable of filtering significantly more water, that probably means it’s built better and made of high-quality materials you can trust.

Keep in mind that the quality of the water being filtered can also impact the lifespan of your filter, so if your municipal water isn’t great, expect to change your filters more often.

Filtering Needs

Some water filters are better at removing some types of contaminants than others. Most under sink filtration systems will remove common toxins like lead, chlorine, and pesticides, but not all of them will efficiently filter other contaminants like algae, molds, volatile organic compounds, or carcinogens.

Before deciding on a water filter, we recommend using a home water quality testing kit that will let you know which contaminants are present in your water source. With that information, you should look for a filter that efficiently removes those specific contaminants.

Another thing to consider is what minerals and compounds you don’t want to filter out of your water. Some filters, especially reverse osmosis systems, remove all minerals from your water supply, even the ones that have health benefits.

If you want your water to contain healthy minerals like fluoride, calcium, potassium, sodium, phosphorus, chloride, and magnesium, look for a filtration system that allows those to pass through.

Ease of Installation, Use, and Filter Change

Some under sink water filters require professional installation, and others you can install yourself in just a few minutes.

The last thing you want to do is damage your plumbing while trying to DIY install a water filter to save money, and then have to spend significantly more on repairs. Avoid that headache by choosing one that's easy to install (or hiring a pro, to begin with).

Also consider how often you will need to change the filters, and how difficult and time consuming that will be.

Some filters have cartridges that twist off easily in seconds, but others require a complete re-installation when they need to be replaced. Depending on the lifespan of the cartridges, that may or may not be worth the hassle.

Water Pressure

Approximately nobody wants to stand at the kitchen sink for what feels like hours to fill one pot, pitcher, or even glass of water. If you don't have great water pressure, to begin with, it's especially important to choose an efficient water filter.

Simple under sink water filters are usually better for this than conventional ones, but not always. Before buying a filter, see if you can find the flow rate first.

Wrap Up

Having the best under sink water filter makes for a great, healthy addition to your household and improves the functionality of your kitchen without destroying it's aesthetic. What could be more important than providing clean water to your household for you and your family?

When it comes down to the nitty-gritty, the best under sink water filter for you is going to be one that doesn't take up too much space, offers the best filtering qualities without filtering out the good stuff, and lasts for a long time.

Our personal favorite of all of the best under sink water filter choices is the CuZn UC-200 Under Counter Water Filter for all of the reasons we've listed above. For most people, this is the best option. You can check it out right here.

Gus Donaldson
About Gus Donaldson

I built houses for over 30 years and recently retired. I've made lots of mistakes and hopefully teach you not to make the same ones. I still love to build and have a garage workshop that I use for hobby projects like the walnut bookshelf I made for my wife. I like to write and let people know that working with your hands and tools does not need to be intimidating.

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