11 Best Under Sink Water Filters of 2023 – Reviews and Buying Guide

If you or your family drink a lot of water, you would probably benefit from an under sink water filter.

Why?

Because filter jugs and other countertop or refrigerator filters just don’t hold enough water if you drink more than a couple of liters a day. And whether you live alone or with scatter-brained teens, you will definitely have come to the kitchen some time to get a nice cool glass of filtered water and found your filter jug empty. 

An under sink filter means that all the water that comes from the faucet it’s attached to (usually the kitchen sink, but some under sink filter lovers add one to bathroom sinks too) is freshly filtered and ready to enjoy.

Why you need an under sink water filter

Having an under sink filter is just easier! Many of the options on this list are really affordable and can be installed DIY if you’ve ever held a wrench.  

And once you’ve spent a few minutes plugging your new filter in (or persuaded/paid someone to do it for you) you simply don’t need to think about it again for six months, a year, in some cases longer.

In short, it will save you time and energy. An under sink water filter will also make sure your whole family drinks filtered water – yes, even if your kid comes in from playing soccer and drinks straight from the faucet they’ll be slurping up filtered water!

In addition to that, an under sink filter makes it easy to use filtered water for cooking, cleaning and even doing the dishes. Can you imagine doing all that with a filter jug? You’d need quite a lot of them, and you would look very strange washing carrots or mopping the floor jug in hand!

Whether you just filter your water to get the best possible taste and smell, or you want to remove contaminants like chlorine, lead and rust, or even heavy metals, there’s an under sink water filter on the market that suits your needs.

The system consists of three distinct filters – a spun poly sediment filter, a catalytic carbon filter, a coconut shell granular activated carbon water filter. As this is a reverse osmosis or RO system, it uses pressure to remove contaminants. In doing so, the mineral content of the water is reduced.

But don’t worry! The Home Master includes a patented remineralization system to add calcium and magnesium to the water not once but twice during filtration. This not only means you’re getting what is essentially mineral water on tap, but it helps your under-sink filter to last longer because the minerals protect against degradation.

This system promises to remove up to 99% chlorine, chemicals, metals, fluoride, total dissolved solids (TDS), pharmaceuticals, and microplastics, amongst other things. It comes with a 5-year warranty, and with an all-in-one modular design it comes ready for DIY installation. 

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The APEC can produce a whopping 90 gallons of pure water per day, which is the most of any 4 RO system I know of. 

The first filter in the system captures bigger particulates. After that, two large carbon block cartridges within suitable housing ensure maximum possible contact time between the filters and your drinking water as they get rid of chlorine and any weird tastes and smells.

Next is the high-rejection TFC RO membrane, which deals with heavy metals amongst other things, and finally a third coconut shell carbon filter to remove any strange flavors or smells picked up during the purification process itself.

This is all coupled with an alkaline filter to ensure delicious, contaminant free alkaline drinking water is available every time you turn on your faucet. 

Of course, with a system this advanced you also get remineralization. APEC are particularly proud of their remineralization technology, which does more than just throw calcium and magnesium at the standard RO demineralization issue. Instead, their remineralization cartridges add a carefully calculated level of US produced calcite.

It takes about an hour to install the APEC ROES-PH75 if you’re vaguely competent with a screwdriver, etc. If that sounds daunting or just boring, a plumber or handyman will be able to install it very easily. 

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The real joy of this filter, though, is that installing it is incredibly quick and easy. It takes an average of 15 minutes but has been managed in much less time too! It can be uninstalled just as easily, making it a great option if you rent your home and a move might be in your mid-term future. 

Additionally, changing the filter cartridges in the Clearly Filtered 3-stage is a doddle – and videos are provided on the company’s website for both installation and filter changes, so you don’t have to scour Youtube to find a guide. 

Filters have a 2000 gallon life, which is pretty standard and means changing the cartridges every few months (which as I’ve mentioned is really easy – just make sure you have enough spares in the house when it’s time to change them).

The three stages of filtration within this system are as follows: 

The primer filter is granulated coconut-carbon, and gets rid of nasty tastes, cloudiness, odors, chlorine and VOCS amongst other common chemicals.

Filter two is a special blend filter which removes heavy metals, herbicides and pesticides, PFAs and more.

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As this is not an RO filter system, natural beneficial minerals like calcium, magnesium, and potassium are left in your water.  This means that your filtered water retains all its natural health benefits, but any dangerous contaminants are removed and it has a guaranteed fresh taste and smell.

The Claryum system is made up of a 20-micron pre-filter, an active carbon filter, and an ion-exchange filter. In tandem, these three filters reduce mercury, chlorine-resistant cysts, herbicides, pesticides, VOCs, pharmaceuticals and chlorine. The 3-Stage is NSF and ANSI certified.

The environment is also taken into consideration with this system, and it has minimal disposable plastic parts within its filters and filter casings. 

Filter change is easy, with a simple twist-off cap to each filter housing. Plus, the Claryum 3-Stage alerts you when it’s time to change your filters, so there’s no guessing-game or repeated water tasting required! Plus, with Clarium’s auto-delivery option for fresh filters, you’ll always have one (or three) on hand when needed. 

This system comes with a faucet included, and as you have to fit that faucet you do need at least rudimentary DIY or plumbing skills to install the 3-Stage. 

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The system features 25-micron pre-filter and two catalytic GAC carbon filters that use premium activated coconut carbon. The casing is also compact making the whole system really easy to fit under sinks of any size, and the roughly yearly maintenance routine of replacing the three filter cartridges is easy. Just remove the cover and replace the cartridge, no mess and no tools needed.

Water pressure should remain between 40-80 psi when you have a Pelican 3-Stage Drinking Filter installed, and the whole thing has a 1-year warranty in case of any teething problems or more serious issues. 

Relative to some competitors, the Pelican is quite easy to fit. It comes with an install kit that includes color-coded fittings to speed up the installation process, but as you have to fit a faucet you do need to be reasonably handy if you aren’t going to call in professional help. The faucets are available in brushed chrome, brushed nickel and copper, so you should be able to find at least an approximate match to your current decor. 

This system is made in the USA using skilled labor, with a mind to environmental sustainability. 

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Despite a low price point, the iSpring RCC7AK boasts 6 filtration stages that not only remove 99% of contaminants like chlorine, lead, arsenic, and asbestos, but also softens and remineralizes your water. 

The six stages of this system include three pre-RO stages – a PP sediment filter, a carbon KDF filter, and a carbon block filter. They remove large particulate matter and chemicals like chlorine, all of which would damage the reverse osmosis filter. 

The reverse osmosis filter uses pressure to remove pretty much everything bigger than a water molecule. Finally, a granular activated carbon filter removes any tastes or smells that may be left in the pure water that has come through your filtration system, and your water is ready to be remineralized and softened. The Alkaline Remineralization process ensures your water is packed full of healthy minerals, and is gentle and alkaline rather than acidic and tough on your clothes, surfaces, skin and stomach.

This filter system is NSF and ANSI 58 certified, and comes with extremely clear DIY installation instructions. It also comes with a kitchen faucet, which, as with many of these filter systems, is quite stylish though it may not completely fit with your current kitchen aesthetic.

iSpring have their own technical videos available through their website, as well as great customer support available online or on the phone. 

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The HydroPerfection offers 9-stages of filtration, purification, and enhancement. This allows the system to remove up to 99% of chlorine & chloramines, chemicals, lead, heavy metals, fluoride, microplastics, and more. 

After water has been filtered by the HydroPerfection it enters a UV sterilization chamber, which kills germs and viruses without changing the composition, flavor or temperature of your water.

Finally, Home Master uses a patented full contact artesian remineralization process to rebalance the PH of your water to a gentle alkaline level (twice, in fact) while enhancing it with small amounts of calcium and magnesium. 

This is a system that was designed to deal with some of the issues RO systems are usually called up for. For example, a built-in pump means that the HydroPerfection reduces water waste by up to 80% compared with its competitors, and it doesn’t need electricity to do it! It also claims to maintain the flow rate of your water, and almost never leak. This is backed by a 5-year warranty.

The HydroPerfection comes with a quick-release faucet that can be added to your existing sink set-up and used for washing fruits and vegetables, drinking, washing hands, and cooking. The system does need to be plugged into an outlet as well as being plumbed into your sink, and though it is possible to install the HydroPerfection DIY it would also be an easy job for a handyman or plumber.

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Although it’s smaller than most under counter water filter systems, the CuZn offers 3-stage filtration, including a micro sediment layer, activated coconut carbon, and a powerful KDF-55 filter. 

The first stage catches small particulate matter, the second deals with bad tastes and odors in your water, and the third reduces levels of lead and heavy metals amongst other things. The CuZn UC-200 has a bacteriostatic coating, meaning that it is not susceptible to mold or bacteria growth.

This is one of the easiest to install under counter filter system options on the market. You simply turn off your water, disconnect the cold water line beneath your sink, and insert the CuZn UC-200. 

There is no upkeep on this filter – rather you replace the unit every five years (or when chlorine test strips show the presence of chlorine in your tap water). With its very reasonable price, replacing the unit every five years should still work out cheaper or as cheap as other leading under sink water filter models, as beyond the initial outlay you also have to purchase replacement filter cartridges for most of them.

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The 2-stage filter removes 99% of lead and chlorine, and sediment from your water, as well as improving the taste and smell of your water. The first stage is a sediment filter with 5-micron precision, and the second is a block carbon filter with 0.5 micro precision. 

This system does not remove heavy metals, so if that’s an issue for you (for example, if you live in an older and unrenovated property or use well water in your home) then you should look elsewhere.

Along with being very affordable at point of purchase, the Frizzlife is very economical in terms of upkeep. New filter cartridges are very economical, and changing them is easy. Just unscrew the top of the Frizzlife canister and swap the cartridges out. You don’t even need to shut off your water, as there is a bypass option. 

As it’s just a carbon filter and sediment filter, this system leaves all the healthy minerals in your water where they are. That means there’s no complex remineralization process, and your water will be roughly the same PH it usually is.

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Once plumbed in (which the company claims takes 3 minutes, though I would definitely allot myself at least 10) the Waterdrop doesn’t affect your water pressure, promising a psi of 60.

Replacing the filters is just as easy, and takes only seconds, but you won’t have to worry about that often as this system’s 10,000 gallon filter life mean you’ll only have to change the filter every 6 to 12 months. 

Given its low shelf price and minimal upkeep, this is a fantastic budget under sink filter system option. Plus, as it can be installed and uninstalled easily leaving no trace that anything has been changed, the Waterdrop 10UA is another great option for renters. 

This system includes a sediment filter, and active carbon filter and a KDF filter, so it deals with sediment and rust, chlorine, lead, odors and unpleasant tastes, and even heavy metals. It doesn’t filter out any essential minerals, leaving your water as rich in potassium, calcium, magnesium and sodium as it was before filtration.

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Filters have to be changed approximately once a year, meaning you don’t have to think much about your APEC WFS-1000 once it’s plumbed in. The system comes with a faucet, so some knowledge of plumbing and DIY is required to install it. It also comes with a 1-year warranty, and promises a clog-free experience along with no water wastage.

The filters are as follows:

First is a high-capacity polypropylene sediment filter which removes dust, dirt, rust and other particles.

Second comes an extruded carbon block filter which removes chlorine, cloudiness, VOCs, unpleasant tastes, and more.

Finally, a second carbon block filter further purifies your water. 

The whole filtration process is quick, meaning that water will flow from your faucet as soon as you turn it on, with good water pressure maintained (up to 85 psi).

The APEC WFS-1000 system does not remove heavy metals, so is not suitable for use with well water or any other water that might contain them. It removes chlorine, sediment and VOCs, and improves the taste and smell of your water to make it not only palatable but irresistible! It also maintains the mineral balance and existing PH of your water.

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Buying Guide to Choose the Right Under Sink Filter 

The two main types of under sink filter are reverse osmosis filters and conventional filters, with a third option of ultra simple under sink filters.

Here’s a short explanation of each, including their pros and cons. 

1. Reverse Osmosis Filter

A reverse osmosis filter uses pressure to force water through a semipermeable membrane. This membrane is so fine that only water molecules can get through, leaving all contaminants behind.

This process is often combined with the various filter types used in a conventional filter, which in a modern reverse osmosis filter are used as the prefilter stage. 

Reverse osmosis filters get rid of more contaminants than any other filter type, but they have two issues.

Firstly, when I say everything I mean everything. That means that minerals and beneficial chemicals like low levels of fluoride are removed from your water along with contaminants.

Secondly, reverse osmosis filters use a lot of water and most of it is simply flushed down the drain. The process produces one gallon of water using one or two gallons to process it which are then flushed. That’s not very environmentally friendly, and if you’re billed for water it can really add up.

The first problem can be solved by a remineralization process, which is sometimes paired up with a process that gives you gently alkaline water. This means your tap water is chock-full of beneficial minerals, but it also means you have to buy mineral cartridges along with filter cartridges and change them regularly.

Unfortunately, there really is no solution at present for the water wastage issue. If you have an eye on the environment or on your own wallet, an RO filter might not be the smartest choice for your needs. 

2. Conventional Filter

Conventional filters utilize sediment filters, carbon filters and KDF filters to remove, respectively, dust, dirt, sand and rust, chlorine and bad tastes and smells, and heavy metals. This is a pretty complete filtration process.

Usually, these filters are housed separately and various flow design methods are employed to ensure a decent level of contact between your water and each of the filters. This can slow water down a little when you first turn on your faucet, but usually pressure is maintained or near-maintained overall.

These filters often come with a faucet, and are reasonably easy to plumb in if you have an okay knowledge of DIY. 

3. Simple Filter

Simple filters are… well… simple. You simply clip or screw them into your cold water line and your water supply flows through them and comes out of your existing faucet. When you remove a simple filter, you simply reconnect the cold water line leaving everything as it was before.

These filters really vary in their specifics. There was a time when they were really minimal, and mostly existed to make unpleasant tasting water more palatable while not actually making it any safer to drink, but in recent years they have become more advanced. 

In fact, the Waterdrop on this list is a simple filter that provides exactly what an average conventional filter usually provides, including a KDF filter for heavy metals.

If you’re a renter, or don’t have a lot of money to play with then look into simple filters. These are also a great option for an office or break room, or anywhere where water flavor is the biggest concern. 

Final Thoughts

Personally, I’m quite environmentally minded so I tend to avoid reverse osmosis filters. And yet, I know plenty of people who swear by them! If that sounds like you, then I’d recommend either the iSpring (as a very good budget option) or the Home Master HydroPerfection. The latter is about as advanced as an under sink water filter can get – the UV chamber in particular is a feature I haven’t seen anywhere else. And yet it’s a really useful one!

Something I really appreciate about the under sink filter market right now is its breadth. There are options for every budget and every situation. I love the neat, environmentally conscious Claryum 3-stage, and I’m equally taken by the stylish, slick and extremely affordable Waterdrop. For me, as a renter, it’s between these two systems, and I think the Waterdrop’s ease of installation and price just pushes it over the finish line to become my favorite from the list.

Of course, your pick is probably different. If you have a larger family, for example, you’re going to want something that can deal with a real high rate of use. And if you’re dealing with particularly contaminated water, perhaps you’ll be springing for that UV chamber!

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Recommended Reading:

• Show Me Light The Light! 6 Best UV Water Purifiers of 2021 – Reviews and Buying Guide
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