Sure, if you have the handyman skills to DIY your own under sink filter go ahead and give it a shot but it’s much easier and more cost-effective to purchase one.
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Are you worried about what is in your drinking water? Or are you tired of buying bottled water?
You’re not alone.
In fact, a lot of people are very concerned about the quality of the water they consume every day.
While there are some ways to improve the quality of your home’s water, one way that many people don’t think about is getting a water filter.
We have spent countless hours researching, talking to manufacturers & customers, learning about new technologies, and testing different filters to determine which under-sink water filters are the best for clean drinking water.
In this review, we will outline the top under sink filters on the market, and explain why they made the cut.
With under-sink water filters, these are the criteria we considered and that you should consider when deciding which water filtration system to go with to get clean drinking water every day.
The main purpose of purchasing under-sink filters is to filter out the contaminants in your tap water. So, you need to make sure it can remove the specific impurities you’re dealing with.
If you don’t know what contaminants you need to remove, be sure to test your water using a high-quality water test kit.
The specific contaminants that a filter can remove vary from model to model, but in order for it to be deemed suitable for drinking water it must meet these standards at the very minimum.
With under-sink filters, the most common types of filters used are carbon, reverse osmosis systems, and ion exchange. The specific types and number of filter stages will determine exactly what the unit can remove during the filtration process, including volatile organic compounds.
| Common Filter Types in Under Sink Units | Contaminants Removed |
|---|---|
| Carbon (Block or Granular) | Chlorine, taste and odors, asbestos, lead, mercury, VOCs, trihalomethanes, disinfection byproducts, some microorganisms |
| Ion Exchange | Minerals (calcium, magnesium), barium, radium, heavy metals |
| Reverse Osmosis (Most Effective) | Most microorganisms, minerals, heavy metals, suspended particles, fluoride, arsenic, nitrates, hexavalent chromium, perchlorate, VOCs, most radionucleotides |
Under sink water filters are generally designed so that you replace the filter cartridges every so often.
This can be done without a plumber, and most filters should be replaced every 6-12 months.
The main things that affect your filter’s lifespan are:
Overall, you want to look for a water filtration system that is durable and which you can easily replace only once every 6-12 months if possible.
Reverse osmosis style filters use water to flush away the contaminants they filter during the filtration process. This water has a higher contaminant concentration and is considered non-potable (meaning it isn’t fit for drinking) or water waste which is not eco-friendly.
On average, RO filters use four gallons of wastewater for every gallon of fresh water generated, and systems that can minimize this waste are ideal.
When comparing the price of under-sink filters, there are two main things to take into consideration:
For example, you see a filtration system that costs only $150, but it needs a plumber to install for $100 and the cartridges are $150 to replace yearly. At the end of five years, you’ll have spent $1,000.
On the other hand, you may see a drinking water filter system that costs $400 upfront but doesn’t require a plumber for the installation, and the cartridges are only $75 per year.
If you go with this one, even though it’s more upfront, at the end of five years you’ll have only spent $775.
Don’t forget to look at the long-term costs and savings of the systems you’re considering as well as the quality of filtration.
Something else to consider is the effect that the filtration process has on your flow rate. The flow of water is measured in gallons per minute or GPM, and it describes your faucet’s water pressure or how fast it comes out.
One of the biggest complaints people have about their under sink system is how it negatively impacts the flow velocity.
There’s usually a trade-off between the level of filtration and flow.
RO filters have a notoriously low rate of flow – but that’s because they filter out the smallest particles. An ion exchange filter has a higher flow velocity, but it doesn’t remove the same amount of contaminants.
The best under-sink water filter will meet the quality standards you need for your water while still maintaining a functional flow.
There are two independent, 3rd-party associations that certify water filters – the National Sanitation Foundation (NSF) and the Water Quality Association (WQA).
If a filtration system is certified by either the NSF or WQA, it’s an extra assurance that the filter meets high-quality standards.
RO filters, for example, may be certified for the NSF/ANSI 58 standard which evaluates things like the filter’s structural integrity, efficiency, contaminant reduction performance, and other criteria.
A carbon block filtration system, on the other hand, may be certified for the NSF/ANSI 53 standard, which evaluates the under sink filter’s ability to remove materials with detrimental health effects.
For more information about water filter certifications, click here.
This is an often-overlooked factor when it comes to buying an under-sink filter, and one which you won’t usually find reliably described on the box.
The cost of engaging a professional plumber to install an under-sink filtration system is certainly going to outweigh any savings gained by opting for a cheaper under-sink water filter.
While most manufacturers will downplay the complexity of installation, only first-hand user experience from customer reviews will give you a true picture of the ease with which water filters are installed.
Using our evaluation criteria above we selected the best under-sink water filters on the market which we have reviewed in detail below to help you decide which filtration system is best for your kitchen needs.
Our #1 recommendation for the best under-sink water filter is the Clearly Filtered 3-stage water filter system.
Clearly Filtered has a history of producing superior products that deliver quality results, and this product is a prime example:
This sink water filter system has three stages of water filtration including a premium carbon priming filter, a heavy metal and VOCs (volatile organic compounds) filter, and a fluoride and arsenic filter.
The carbon priming filter contains granulated coconut carbon which removes chlorine, tastes, odors, cloudiness, and colors.
The heavy metal and VOC (volatile organic compounds) filter remove 99% of heavy metals, pesticides, and herbicides, and the fluoride and arsenic filter removes 99% of fluoride.
The filtration capability of this under-sink filter is one of the best in removing more than 200 contaminants.
This under-sink filter also comes with a pretty solid filter lifespan at around 2,000 gallons of water or around 12-15 months before needing replacement and the replacement filters are a breeze to install.
Lastly, this is one of the easiest under-sink water filter systems to install. They claim anyone can do it and it takes only 5-10 minutes.
Bottom Line: All in all, if you’re looking for the best under-the-sink filter for your home then you need to purchase this Clearly Filtered model. You won’t be disappointed.
Another one of our top picks for the best under-sink water filters is the Waterdrop G3 reverse osmosis filter system.
Waterdrop is becoming a top brand in high-quality innovative water solutions and this model is one of their best products.
This is one of the most powerful under-sink water filter systems with an impressive 400 gallons per day capacity, which would suit even a large household.
The powerful RO system removes 99% of TDS, it’s NSF certified, and it fits nicely under your sink.
The Waterdrop G3 has a 7-stage filter system, making it one of the most effective and thorough water filter systems on the market. These are the following stages and components:
This sink water filter also reduces wastewater by 300% more than other RO units, which is more eco-friendly, the filters are easy to change, and it has the highest level of new technologies.
Bottom Line: If you’re looking for an under-counter option that uses RO filtration to get your water pure and clean, then this water filter system from Waterdrop is your ideal choice.
Another one of our top picks is the Aquasana OPTIMH20 RO and Claryum filter.
This water filter system also utilizes RO but is more sparing on your flow velocity, it removes over 87 contaminants, is NSF certified, and is a more budget-friendly option.
Aquasana is another one of the leading brands in the water filtration market and they produce reliable, top-quality products that you can rely on to get clean water.
This under-sink water filter system model from Aquasana is a RO system, and it incorporates six different stages of filtration to remove over 89 different contaminants:
It comes with filters that will last from 6-12 months, an average rate of flow, and a high level of filtration capability.
The only downside with this sink water filter system is the wastewater it produces at 4 gallons of waste to 1 gallon purified ratio.
Bottom Line: If you’re looking for an under-counter option that uses RO filtration to get your water pure and clean, then this water filter system from Waterdrop is your ideal choice.
Next is the PDF-1000VF under-sink filtration system by Pelican Pentair Water.
Pelican Pentair Water is an established and trustworthy brand, and you can count on them to deliver a system that provides clean and tasty water.
This system has a 1,000-gallon capacity, doesn’t generate wastewater, and contains a metered flow control.
This Pelican model is a 3-stage filtration system that utilizes both GAC and mechanical filters.
Overall, we think this is an excellent carbon undersink water filter if you don’t need reverse osmosis.
Bottom Line: Overall, if you’re looking for another affordable, quality system, then this model from Pelican is one to consider.
This 3-stage filtration system from Aquasana has all of the features you’d expect from an under-sink tap water filter, at a truly affordable price, from a leading brand, and including a brushed nickel faucet.
Unlike their RO filter, this Aquasana product utilizes a multi-stage carbon filter with Claryum to achieve filtered water.
The difference between this unit and the other one we featured above is the RO system.
RO just provides an added level of filtration and removal of harmful contaminants but this 3-stage system is a great option for the homeowner who doesn’t need to remove additional contaminants.
Bottom Line: This is one of the budget choices we included on our list. Despite its cheap price, this sink filtering system is capable of producing clean and crisp water, like the expensive models.
Next is the Waterdrop 3-stage ultrafiltration under the kitchen sink system.
Waterdrop’s version of the carbon filter has several advantages including an integrated waterway and an indicator system that lets you know when the filters need to be changed.
The Waterdrop ultrafiltration system does not require an under-sink electricity supply and produces quality purified water with zero wastewater.
It uses the following stages:
The main difference between this model and the other one featured above is RO filtration. This unit is a standard carbon filter system that will remove most of the main water contaminants in your feed.
Bottom Line: Overall, this system from Waterdrop is an innovative, all-in-one, intelligent purification system that is super cost-effective and easy to install.
Ecosoft’s 3-stage tankless under-counter water filter was a real surprise for us and snuck into the top 10.
This gem doesn’t have a big-name brand behind it, but the quality of water it produces certainly earns it a place on this list.
This 3-stage filtration system is made with the following components:
Overall, it’s a good filter for a budget option if you aren’t looking to spend the kind of money one of our top RO-style picks calls for.
Bottom Line: Everything you need for installation comes in the box, and fitting is simple enough for most competent people. The low water pressure flow rate is a drawback though.
Another good option is the iSpring RCC7AK model.
This model has 6-stage filtration with alkaline water remineralization and it is a RO system.
Many users have reviewed this product, and the overall consensus is that it is one of the top reverse osmosis under sink filtration systems at an affordable price.
We also did a full iSpring filter review if you want more information about the company.
This filter has top-of-the-line filter capacity and reverse osmosis filters. It is made of the following stages:
For an under-sink filter that also comes with RO and demineralization, this product is a great bang for the buck.
Bottom Line: Overall, if you’re looking for a sink reverse osmosis system option this is another good product to consider.
With an average 4.8 star rating from almost 1,500 Amazon reviews, it would be fair to say that the UC-200 is a popular under-sink filter…and 91% of reviews rate it as five stars.
This product incorporates several different filtration components to purify your water:
The best feature of this filter is the 5-year filter life and the high filter capacity 3-stage system it comes with.
It’s easy to install and very cost-effective for someone looking for a standard carbon under sink filter option.
We also reviewed this unit in full detail at our CuZn UC-200 review.
Bottom Line: Overall, you can get great value from this popular filter and still remove most contaminants.
Last on our list is the APEC WFS 1000 model. This honorable mention is another budget option that offers good filtration at an affordable price.
This under-sink system uses a 3-stage system to filter out impurities similar to many of the other filters on our list.
Each filter in this system is designed to last around 1 year and the system is simple and easy to use.
Overall, APEC is a solid brand in the water filtration market that competes with our top picks.
Bottom Line: Overall, this model does not match our top picks, but if you’re looking for an average budget option then it’s worth a look. This product is also made in the USA, it’s earth-friendly and easy to install.
It’s easy to be swept away in a flood of technical jargon and perplexing comparisons when it comes to water treatment.
Our goal is to make these useful systems as simple as possible so that you know what matters and what doesn’t, allowing you to pick the finest under-counter water filter for your needs.
An under-sink water filter is a filter that is installed beneath a sink (usually in the kitchen) and connects to the incoming cold water feed line.
Water passing through the filter is purified and delivered from the dedicated faucet with higher quality and fewer contaminants, tastes, and odors.
These units are usually best for people looking for just drinking water filtration and who aren’t as concerned with having all their home water filtered.
Most under-sink filters use a combination of activated carbon block filters and pre-filters to trap sediments and organic materials within the incoming water feed as well as RO membrane filtration.
Filters or casings can be bacteriostatic or are often given an antimicrobial coating to prevent mold and bacteria growth within the filter.
UV filtration and KDF filters are also often used in under-sink models.
Learn more about the different types of under sink water filters.
There are 3 defined types of under-counter water filters:
The differences between each have been described below.
Conventional under-counter water filters connect to the existing cold water line to the sink and feed a separate faucet (usually included with the filter kit). These systems can be more complicated to fit.
Simple water filters are fitted in line with the cold water feed to your current faucet. This minimizes complications when installing as fewer plumbing changes are required, and it also removes the need to drill through your countertops and fit the additional filtered faucet.
Simple water filtration systems tend to require replacement filters more regularly because they are filtering all water that goes to the faucet. This causes a significant increase in the wear and tear on the filter in a busy home.
Reverse Osmosis (RO) filters work differently from other filtration systems.
Most other filters use the incoming water pressure to push feed water through the filtration devices designed to trap sediments, destroy organic particles such as bacteria, and filter out contaminants like pesticides and metallic elements (depending on the model).
RO uses pressure across a semi-permeable membrane to force pure water to one side of the membrane while contaminants remain on the other. This results in purified water which is stored in a tank for use at the faucet, and a brine mixture containing all of the contaminants, which is then flushed away as waste.
The nature of the flushing process means that a significant volume of water is wasted with RO systems, and the need for pre-filters and a storage tank results in a bulkier system needing to be situated below the sink.
There are many benefits to using an under-sink water filter in your home:
The reality is that water quality is becoming more widely discussed in America, and catastrophes such as those seen in Flint, Michigan have made more and more people aware of potential contaminants within their water feed.
Under sink water filters are a simple, cheap, and reliable way to achieve this.
You may be wondering if you have other options besides an under-sink water filter, and the answer is yes. You can also look at getting a countertop filter, and we’ll take you through the pros and cons of both.
The installation method will vary according to the model of the under-sink water filter that you purchase and you should always follow the manufacturer’s instructions.
However, fitting the units will usually follow the same steps:
See our complete guide on how to install an under-sink filter & how much it costs.
The manufacturer will always include guidelines for the expected cartridge filter life within the product literature however as you get used to using your under-sink water filter you may notice some early warning signs that the filter is coming to the end of its life.
This can be a sign that the tiny pores within carbon filters are becoming clogged up with residue.
As a filter becomes clogged with contaminants removed from the water feed it will begin to allow some particles through that would otherwise have been filtered – these will affect the taste of the water at the faucet.
This can be a sign that the tiny pores within carbon filters are becoming blocked as they reach capacity or that the RO membrane is becoming more permeable. Check that all valves are properly open but if the flow rate to other outlets is unaffected, it is time to buy a new cartridge.
See our guide on how often you should change your under-sink filters and how to change them.
Here are some questions about acid neutralizers that I get very often:
There is no one best filter because it depends on your water quality and home needs. If you’re looking for the highest filtration capability go with a reverse osmosis under sink model.
If you just need pure filtered water with the normal contaminants removed check out the carbon under-sink models.
If you want to remove the most contaminants under counter reverse osmosis systems will be best.
If you just want a solid water filter at a reasonable cost, check out the sediment and carbon filters that fit under the sink.
No, an electricity source is usually not needed since these filters hook up to your main cold water supply line.
Sure, if you have the handyman skills to DIY your own under sink filter go ahead and give it a shot but it’s much easier and more cost-effective to purchase one.
15657 N Hayden Rd #1162
Scottsdale, AZ 85260
United States
602-780-2598
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