This post may contain affiliate links. For more information, please see our affiliate policy.
Clean water is one of the most important things you can have in your kitchen. While you can certainly use a pitcher filter to purify your water, under sink water filters are much more convenient since you don’t have to constantly refill them. They do require some initial installation, but it’s easy to do yourself. And once the work is done, all you have to do is change the inner filter every 6 months or so and you’ll be good to go!
To come up with this list of the best under sink water filters, Meggan and I looked at a number of factors. We considered the type of filters, which plays a role in what the filter will remove, plus flow rate and ease of installation. We also thought about the size of the filter and made sure to include options for large and small kitchens. From single filters to higher-end 8-stage filtration models, below are our top picks.
Our Top Picks
- Best Overall: APEC Water ROES-50 – $199.95 at Amazon
- Best Budget Under Sink Water Filter: Waterdrop 10UA – $51.99 at Amazon
- Best Reverse Osmosis Under Sink Water Filter: Waterdrop G3 Reverse Osmosis System – $539 at Amazon
- Best Multi-Filter Under Sink Water Filter: Aquasana Claryum 3-Stage Max Flow – $$134.99 at Walmart
Reviews of The Best Under Sink Water Filters
1. Best Overall: APEC Water ROES-50
Under-sink water filters can look intimidating, but the APEC Water ROES-50 is easy to install, effective, and reasonably priced, which is why it’s our top pick. It has 5-stage filtration, which can remove most contaminants from your water. To do this, it uses three carbon filters, plus a sediment filter and a reverse osmosis membrane that takes out all kinds of impurities, like heavy metals, fluoride, and weird tastes and smells.
It’s also guaranteed to filter out “forever chemicals” PFOA and PFOS, which many filters don’t. works for both tap and well water, so you can use it no matter your water source.
We also love that it comes with a faucet—you can choose from brushed nickel or chrome to match your kitchen—and a 4-gallon storage tank that keeps purified water at the ready whenever you need it.
The Specs:
Dimensions: 16″ W x 5.25″ D x 17.5″ H
System capacity: Up to 50 gallons per day
Flow rate: 0.035 GPM
What I Like:
- Easy to install
- Comes with storage tank
- Filters “forever chemicals”
What I Don’t Like:
- Water flow rate can be slow
- Noisy
- Some don’t like the water taste
What Others Are Saying:
The Apec Water ROES-50 has more than 14,000 reviews on Amazon with an average rating of 4.7 out of 5 stars. Plus, National Geographic chose it as the best reverse osmosis under sink water filter and Real Simple picked it as the best for well water.
Buy the APEC Water ROES-50:
2. Best Budget Under Sink Water Filter: Waterdrop 10UA
The Waterdrop 10UA isn’t as heavy-duty as some of the other multi-filter options, but it’s still a great option at a fair price. This one-filter model removes heavy metals, odors, chlorine, and both small and large sediments. It’s not effective on PFOA and PFOS like more expensive reverse osmosis filters, but the trade-off is a high flow rate.
It also has one of the longest lifespans of all the filters we recommend and can filter up to 8,000 gallons of water before you need to replace the filter. And because there’s only one filter, it’s really compact, making it a great choice for smaller under-sink areas.
The Specs:
- Dimensions: 3.6″ W x 3.85″ D x 12.3″ H
- System capacity: Up to 8,000 gallons
- Flow rate: 0.75 GPM
What I Like:
- Inexpensive
- Easy to install and maintain
- Compact
What I Don’t Like:
- Only one filter type
- Doesn’t filter PFOA or PFOS
- May not change water taste
What Others are Saying:
The Spruce chose the Waterdrop 10UA as the best under sink water filter for apartments, while Real Simple named it the best budget pick. It’s a popular pick with more than 8,200 reviews and an average 4.6-star rating on Amazon.
Buy the Waterdrop 10UA:
3. Best Reverse Osmosis Under Sink Water Filter: Waterdrop G3 Reverse Osmosis System
Reverse osmosis water filters are one of the most effective—they remove up to 99.99% of contaminants! This includes “forever chemicals” like PFOA and PFOS that are known for contributing to a whole bunch of health issues. While you do have to pay a premium for this—this is the most expensive under sink water filter we recommend—we think it’s worth it.
We like this system in particular because it has 8-stage filtration and comes with a smart display faucet that shows you the quality of your water in real time. And while most reverse osmosis filters come with a separate tank, this one has a “tankless” design that streamlines installation and saves space under your sink for other necessities. Though its a but more pricey, the design also makes it easier to swap the filters, and the convenient filter change alert will let you know when it’s time to replace them.
The Specs:
- Dimensions: 18.11” W x 5.67” D x 17.73” H
- System capacity: Up to 400 gallons per day
- Flow rate: 0.28 GPM
What I Like:
- Takes up less space than other RO systems
- Smart display shows water quality
- Easy to install and change filters
What I Don’t Like:
- Expensive
- Slower flow
- May need to buy separate adaptors
What Others Are Saying:
Good Housekeeping found the Waterdrop G3 to be the best reverse osmosis system they tested. This model also has a 4.5-star average rating from more than 2,700 reviews on Amazon.
Buy the Waterdrop G3 Reverse Osmosis System:
4. Best Multi-Filter Under Sink Water Filter: Aquasana Claryum 3-Stage Max Flow
Aquasana is one of the most well-known names in water filtration, and the products live up to the hype. The Claryum 3-Stage Max Flow is our favorite from the brand because it combines three types of filters and has a high flow rate, so you don’t have to worry about barely there water pressure. This filter removes up to 78 different kinds of contaminants, including chlorine, heavy metals, PFOA/PFOS, and pesticides.
Another thing to note is that it doesn’t remove total dissolved solids (TDS). This can be a good thing since it will leave behind minerals and electrolytes, but keep in mind that it may also leave some particles you don’t want. We also like that it comes in three finishes—brushed nickel, chrome, and bronze—so it fits in more seamlessly with different kitchen aesthetics.
The Specs:
Dimensions: 12” W x 4.25″ D x 12.85″ H
System capacity: Up to 800 gallons
Flow rate: 0.72 GPM
The Pros:
- Filters many contaminants
- Easy to install
- High flow rate
The Cons:
- Doesn’t reduce TDS
- Some report leaking
- Connectors are made of plastic
What Others are Saying:
Wirecutter, Forbes, and Good Housekeeping all recommend the Aquasana Claryum 3-Stage Max Flow Water Filter. It also has an average 4.4-star rating on Walmart from more than 1,350 reviews.
Buy the Aquasana Claryum 3-Stage Max Flow
Other Under Sink Water Filters to Consider
Aquasana Claryum 2-Stage
Unlike some other filters, this has two stage filtration instead of three. Because of that, it’s not as effective at removing contaminants. If you’re going to spend the money on a water filter, you might as well pay a little more and get the 3-stage over this one. That being said, this filter is highly rated and still a good option for those on a tighter budget. The Aquasana Claryum 2-Stage is available at Amazon for $124.99.
Waterdrop Ultra-Filtration Stainless Steel Water Filter
This water filter has a beautiful stainless steel design and could be a good option for those who want a more elevated look. It’s similar in function to the other 3-stage filters from Waterdrop. However, it doesn’t have as many reviews as other similar models from the brand, so it’s likely a safer choice to go with the tried-and-true options. The Waterdrop Ultra-Filtration Stainless Steel Water Filter is available at Amazon for $189.99.
Waterchef U9000
This model is recommended by The Spruce, but it’s much more expensive than other water filters that work in a similar way. Plus, there aren’t a lot of reviews to back up its effectiveness. It could be a good compact option for those who have limited space under their sink, though. The Waterchef U9000 is available at Amazon for $468.95.
Culligan RC-EZ-4
This water filter is highly rated and likely very effective, but it’s expensive for a single-filtration unit. There are other comparable options for a more budget-friendly price. The Culligan RC-EZ-4 is available at Amazon for $96.99.
Why You Can Trust Us
I’m Lindsay, a functional nutritionist, recipe creator, and product reviewer with almost 15 years of experience testing kitchen products and making product recommendations. You can find my work across a variety of digital publications, including The Spruce Eats, Better Homes and Gardens, Forbes, and Eating Well.
I worked on this roundup of the best under sink water filters with Meggan, Executive Chef and head of the Culinary Hill Test Kitchen. Together, we looked at the most popular options and narrowed them down by filtration type, flow rate, ease of installation, size, and price. We researched customer reviews and also read through recommendations from other professional product reviewers to finalize our top picks.
Everything to Know Before Buying an Under Sink Water Filter
What to Consider Before Buying an Under Sink Water Filter
Filtration: Different filters are designed to remove certain contaminants. Many of them filter a wide range of things, from heavy metals to excess minerals and even “forever chemicals.” Ideally, you want to get your water tested to see exactly what’s in it and what you need to filter out an choose a water filter that best suits your needs. If you can’t get your water tested, choose a filter that removes as many impurities as possible—that way you’ll have all your bases covered!
Installation: Most under-sink filters are designed to be easy to install. You connect one line to the cold water and another to a dispenser that sits next to your kitchen faucet. If you don’t already have one, this will require drilling into the countertop to install correctly. This is something that can be done on your own, or you can hire a plumber. If you do decide to do it on your own, check customer reviews to see how easy (or hard) they say installation is.
Flow rate: You might also want to consider the flow rate, which measures how much water can move through the filter in a given amount of time. The flow rate, which is usually measured in gallons per minute (GPM), determines how much water pressure you get. A higher flow rate means your water will come out faster. This may not matter much if you’re just pouring yourself a glass of water once in a while, but if you want to use the filter to fill up pots or coffee machines, you’ll likely want a higher flow rate to get the job done faster.
How Does an Under Sink Water Filter Work?
The exact process depends on which type of filter you get, but generally, an under-sink water filter uses water pressure to remove impurities. Under sink water filters use a pump to bring water through a filter that removes impurities (like rust) and odors (like chlorine). Filters also help give your tap water a more pleasant taste.
If you opt for a reverse osmosis system, another round of filtration occurs, pushing water through a thick membrane at a high pressure, further reducing the contaminants in your water. Once the filtration cycle is complete, the under sink system drains the wastewater, and the clean, delicious water goes to your faucet.
How Do You Install an Under Sink Water Filter?
This depends on the exact filter, too, so make sure you’re always reading and following your manufacturer’s instructions! That said, first, you have to shut off the cold water and then remove the existing connection. Using an adapter that’s included with your filter, you’ll connect tubing from the water filter to the water valve and then connect that to the cold water connection. Depending on the type of filter, you may need to also install a water tank and/or a separate water faucet. This is more common with reverse osmosis filters.
If you’re nervous, you can always have a contractor install one for you!
How Do You Change an Under Sink Water Filter?
You’ll need to change the filters in your under sink system regularly—about every 6 months on average—to make sure it’s running its best. To do so, you’ll turn off the water, and then open the housing where the filters are kept. Remove the old filters, replace them with the new filters, and then tighten the housing back up. Here’s a helpful video that shows how to change the filters in an Aquasana system, specifically.
Depending on your system, you’ll typically have anywhere from one to five filters to change. Exactly when you’ll need to change these filters depends on how much water you use.
Why Would You Need an Under Sink Water Filter?
Both tap and well water can be full of impurities and contaminants. An under sink water filter removes these contaminants so you can drink fresh, purified water. You can certainly use a pitcher filter that you keep in your fridge, but these are less convenient since they need frequent filling. Under sink water filters constantly filter your sink water without needing a refill—all you have to do is change out the filter when it’s time.
Prices were accurate at time of publication.
