The under-sink water filter is one of the most advanced water treatment systems you can invest in for your home. They require little maintenance, filter thousands of gallons of water, and are stowed out of sight.

Like most water filters, there are many under-sink filters to choose from. Some have multiple systems to filter the water, while others have only a single filter.

Most under-sink water filters aren’t cheap. With their streamlined designs and advanced filtration systems, you’re going to pay a little more.

Before you buy your first under-sink water filter, here’s what you need to know.

What's an Under-Sink Water Filter?

Are you wondering exactly how an under-sink water filter works? Well, it’s a type of water filtration system that removes most water contaminants, including metals, viruses, and germs from your drinking water.

As the name immediately tells you, these filters live under your sink, which is perfect for people who have small kitchens or limited counter space, or don’t want to see the water filter each time they go in their kitchen.

Under-sink filters are generally more advanced than other water-filter types. Some systems have multiple filters and a separate faucet, so if you don’t want something that elaborate, there are simpler water-filter options that you can choose.

Now, let's look at 10 highly-rated under-sink filters listed in no particular order:

CuZn UC-200 Under Counter Water Filter

This non-reverse osmosis water filter is the perfect solution for filtering municipal tap water.

Filtration

The UC-200 houses a three-stage filtration system. The first filter removes larger contaminants such as rust and sand; the second carbon layer cuts out the chemical contaminants and odors; and the third layer reduces scale buildup from algae, mercury, and other inorganic contaminants, while allowing healthy calcium and magnesium through.

Pros and Cons

This under-sink water filter is easy to install, compact, and compatible with hot water. It has a long filter life of about five years but doesn’t remove all total dissolved solids or TDS.

APEC Top-Tier Alkaline Mineral pH 6-Stage

This reverse-osmosis (RO) water filter is another great filter that eliminates the toxins but keeps the healthy minerals.

Filtration

This model boasts a whopping five stages of filtration, followed by alkalization. The filtration process starts by removing large particles such as rust and dust. The following filters take out the chlorine, odor, lead, bacteria, and more.

The final stages include the alkalization process, which adds a small, healthy amount of calcium carbonate to improve the water’s smell and taste, and also raise the pH level by one or two points.

The storage tank contains an activated carbon filter that keeps the water smelling and tasting fresh.

Pros and Cons

Your water will taste delicious and have added health benefits with this five-stage filtration system. It comes with a separate faucet and installation instructions.

The downside is that this filter causes some water waste. The installation process isn’t terribly difficult but requires some time and drilling. You may want to consider hiring a plumber or other professional.

Doulton W9330958 SuperCarb

This smaller under-sink water filter has a four-stage system that leaves your water tasting and smelling delicious.

Filtration

The first stage uses a carbon filter that removes pesticides, particles, and parasitic cysts from the water. The second stage filters out bacteria and also includes a self-sterilization feature that prevents bacteria from lingering.

The final stages remove chlorine and heavy metals, leaving you with crisp, fresh drinking water.

Pros and Cons

A smaller size means it takes up less room under your sink. It also has a very durable casing. The only downside is that the installation process requires extra parts not included with the system.

Aquasana AQ-5300.55

If budget is an issue, this three-stage under-sink water filter is worth checking out. It's more affordable but still offers safe and great-tasting water like other filters on this list.

Filtration

The three stages in this filter trap most contaminants, including pesticides, chlorine, heavy metals, and volatile organic compounds (VOCs). The filters last for about six months but are very easy to replace. Simply twist off, replace, and twist on for a fresh new filter.

Pros and Cons

The system has a notification feature that lets you know when it’s time to change your filters. A customizable faucet comes with the system, so the finish can match your existing fixtures. Also, as mentioned before, the price is right on this model.

The one con is the low-quality O-rings. After a couple of years, they may fail, but if you contact the company, they’ll send you a new one for free.

Woder 10K-DC

This high-capacity under-sink water filter attaches directly to your water valve. There’s no separate sink, making installation quick and easy.

Filtration

The Woder 10K-DC has 2 WQA (Water Quality Association) certifications for its clean odorless taste and lead-free compliance. Other contaminants it removes include heavy metals, chlorine, VOCs, mercury, and more.

Its streamlined and direct attachment design means all your water coming from your main faucet will be clean and safe to drink.

Pros and Cons

The filter is very easy to install and maintain. It doesn’t cost a fortune, which makes it a great choice for anyone with a budget.

Filtrete Advanced Under-Sink Water Filter

Simple, affordable, and efficient are the words that sum up Filtrete’s Advanced Under-Sink Water Filter.

Filtration

With some affordable filter models, you risk losing quality and reliability. However, this water filter removes the most common contaminants — microbes, bacteria, soil, heavy metals, and rust — from 2,000 gallons of your drinking water.

It also reduces any chlorine smell to produce great-tasting and odorless water.

Pros and Cons

Despite its small size, this filter does an amazing job removing contaminants. However, it doesn’t have the longest life. The instructions say that the filters last about six months, but you may need to replace them closer to every four months.

Home Master Under-Sink Reverse Osmosis Filter

Are you looking for an under-sink water filter that can provide you with truly pure and healthy drinking water? Then you must check out the Home Master reverse-osmosis system.

Filtration

This is a — count 'em — seven-stage water filter system that removes 99% of contaminants, such as bacteria, cysts, lead, and many more.

After the filtration process, the system adds calcium and magnesium minerals to help promote health. It filters 3,000 gallons, meaning you only need to replace filters about once a year. The system comes with a separate faucet and doesn’t reduce your water flow.

Pros and Cons

The cons are the hefty price tag and the fact that this filter also creates wastewater. However, Home Master has a series of other water filters, including the TMHP for well water, that allows you to choose the option that best fits your needs.

iSpring RCC7AK Reverse Osmosis

Consisting of a multi-stage filtration system, the iSpring RCC7AK under-sink water filter produces clean, great-tasting water.

Filtration

The six-stage system works together to eliminate thousands of contaminants from your water, including hormones, asbestos, arsenic, and bacteria on top of other common contaminants.

After the filtration process, the iSpring water filter polishes the water with added calcium and magnesium, alkalizing the water and giving it a slightly sweeter taste. Depending on the quality of water and the amount you use, the system will last about a year or longer before needing replacement filters.

Pros and Cons

The system produces more wastewater than other RO water filters. If the water pressure in your home is lower than 50 PSI (pounds per square inch), consider a permeate pump to decrease water waste and improve water flow.

APEC Water Systems RO-90

Tested by the WQU, the APEC RO-90 under-sink water filter removes up to 99% contaminants.

Filtration

The system is complete with a three-stage filter, a holding tank, and a separate sleek chrome faucet. This system removes lead, fluoride, viruses, and many other contaminants from your water.

Each filter is larger than average under-sink filters, which decreases filter changes to once per year.

Pros and Cons

While the directions are easy to understand, this system can take some time to install. It offers great water pressure but maxes out at 85 PSI.

Express Water Reverse Osmosis

The Express Water RO has four stages to ensure your water is clean and pure after filtration.

Filtration

Like most under-sink water filters, Express eliminates common impurities like chlorine, lead, and bacteria, plus many more. Other systems in the Express series eliminate additional contaminants such as iron and also offer an alkalization stage.

Pros and Cons

Setup is fairly easy, but professional installation might be needed for people who aren’t savvy with plumbing. Filter changes are easy, but they need to be replaced at least twice per year to maintain quality water.

Invest in a Quality Under-Sink Water Filter

With the right under-sink water filter, you and your family can relax knowing your water is safe and clean. Each crisp sip will bring you a moment of water zen.

If you have questions or concerns about under sink water filters, send us an email. We’re here to help you with any of your water needs.

Water Providers