Best Under Sink Water Filter

An under sink water filter system is not the first thing that comes to mind when you think of home appliances, yet I think it is something everyone needs. Technically, most tap water is considered safe to drink by the EPA, but the acceptable level of contaminants that the EPA sets for safe drinking water is significantly high, so you must take your health into your own hands. This article will help you choose the best under sink water filter on the market and present you with the pros and cons of all the products.

iSpring RCC7AK 6-Stage Under Sink Water Filter

This is one of the most praised products on our list. After considering what it can do and correlating that with the price, it’s easy to see why this model has such high ratings. The RCC7AK is an under-counter filtration system that protects against different types of contaminants with a three pre-filter system. Contrary to the standard 5 stage system that leads to slightly acidic water, the iSpring RCC7AK includes an additional sixth filter. This alkaline remineralization filter produces balanced alkalinity and gives the water a more natural taste. There is a 3-year manufacturer’s limited warranty.

iSpring RCC7AK Reviews

It is easy to tell from the reviews that this was designed for self installers; the entire system fits perfectly under a standard-sized kitchen sink. People have received all the tubing required to build it, and replacement parts are easy to find and cheap on their website. If you are someone who moves around a lot, this can be the perfect system for you as it is not a hassle to install. Users of this system have reported the total dissolved solids being around 24-32, but this depends on your initial TDS. According to some people, the water filtered with this system tastes even better than bottled water. Customers have had some experiences of pieces arriving faulty, but most have received free replacements after contacting customer service.

iSpring RCC7AK Pros:

  • Fairly simple assembly, most required tools included.
  • Technical phone support is available.
  • It can be hung on the sidewall, takes up very little space.

iSpring RCC7AK Cons:

  • 3 gallons of water are wasted per 1 gallon of water purified.
  • The filter sometimes lasts shorter than other systems.
  • No UV light to kill bacteria and other microorganisms.

Culligan US 1 EZ-Change Under Sink Drinking Water Filter

The RC-EZ-1 under sink water filtration system comes with a faucet that can be installed in most sinks and provides cleaner water for cooking and drinking. The filtration cartridge can filter up to 3,000 gallons and lasts up to one year. The replacement filter cartilage is super easy to install; all you’ll need to do is to twist the old one off and the new one on. You should know that this kit works only on sinks that do not have faucets with factory installed water lines.

As the parts for this under cabinet water filter are plastic, you should opt for another water filtration system if your water pressure is significantly high. If your sink is modern, you will need to purchase a 3/8 adaptor additionally. Replacement filters cost only $11.29 on Amazon and are easy to operate, just a twist and turn. This under sink water filter system also comes with a faucet that is very attractive with a shiny exterior and oval base. There are silicone rings that are for the underside of the faucet and beneath the cabinet to ensure a tight fit. Make sure to have some plumber’s tape laying around for extra secure attachments. If you are looking for something simple that doesn’t cost too much and gets the job done, then this is the filtration system for you.

Culligan US 1 EZ-Change Reviews

For some customers, installing this was their first plumbing experience, and it went very well. The reviewers confirm that this kitchen water filter indeed does last a year and even more without any leaks. People have not noticed any solids or impurities in the water, and it tastes great too. Any odors and metallic tastes in the water are removed. A few complaints have been voiced about the plastic being easily broken or not fitting the place intended for the hose, but these can be easily replaced with inexpensive parts that fit your specific sink.

Culligan US 1 EZ-Change Pros:

  • Budget-friendly price on Amazon.
  • Easy installment.
  • Good pressure.

Culligan US 1 EZ-Change Cons:

  • Sometimes leaks.
  • Plastic, Non-durable parts.
  • Some extra parts needed.

Woder WD-10K-DC Ultra Under Sink Water Filtration System

The Woder drinking water filter system uses a unique selective filtration system that removes contaminants while leaving in all essential minerals to pass through. The Woder 10K is very durable and can filter 10,000 gallons or around three years of use. It requires no plumbing and comes with hoses that fit standard water valves under kitchen and bathroom sinks. You can have complete confidence in this water filtration system as WQA has certified it for chlorine, taste, odor, and lead-free compliance.

Woder WD-10K-DC Reviews

This system is known among users for having highly durable filters that last multiple years. That is almost six times as much as competitor filters. If you use less than 10 Gallons of tap water a day, this filter can even last you five years. There have been some complaints of very low water pressure after several months of installing this sink water filter, so if your flow is weak, to begin with, then you should consider looking at other options.

The water tastes great, similar to bottled water. Some unique praises that customers have voiced are that hands aren’t left feeling dry after washing dishes using this water, which is a great sign. Keep in mind that this filtration system works only with cold water. After installing this system, water that used to be foggy and would have particles comes out crystal clear. This product also includes a 1-year replacement warranty, and many customers have received free replacement filters after having e-mailed them regarding issues with their current one.

Woder WD-10K-DC Pros:

  • Great customer support.
  • Easy installment.
  • Keeps essential minerals.

Woder WD-10K-DC Cons:

  • Low water pressure.
  • Not suitable for salty, softened or well water.

APEC Water Systems RO-90 Reverse Osmosis Water Filter

The APEC Water System is one of the best under counter water filters in the market right now. This under sink reverse osmosis water filter system requires much fewer replacements and maintenance than the other options on this list. It has two large super capacity filters, meaning it has twice the contaminant removing capacity compared to smaller filters that clog up quickly and require constant filter changes. It is a bit higher in the price range yet makes up for it in quality and durability.

APEC Water Systems RO-90 Reviews

The APEC water filtration system reviews are overwhelmingly positive, with some people calling it perfect and flawless. The reviewers have mentioned that the packaging of this product is excellent, and the installation process is relatively simple, takes around one hour, and everything connects as it should. The only thing they’ve noted here is that you will need to drill a hole, so if you have granite counters, other customers recommend hiring a professional to do this step.

A faucet is also included and is aesthetically very pleasing. Customers praise the taste, saying it is even better than tap water. For such a big setup, it is also surprisingly quiet and doesn’t disturb you at all. The output of the APEC RO–90 water filter for sink makes it ideal for potential buyers who require a higher than average water filtration. Some customers say that the filters are a bit harder to install than usual, but they last up to 12 months, so it’s worth the extra effort. The filtration level is around 90%-97%, which is significant compared to other systems with this price. Keep in mind that you should not drink the first tank of filtered water and drain it instead. Some customers started with a TDS level of around 500 and got it down to as low as 40 after using this filtration system.

APEC Water Systems RO-90 Pros:

  • Great customer support.
  • Cheap maintenance.
  • High output.

APEC Water Systems RO-90 Cons:

  • Pricey.
  • No remineralization.

CuZn UC-200 Under Counter Water Filter

The CuZn UC-200 under counter water filter is a #1 best seller on Amazon and has fantastic customer reviews. It is one of the best under sink water filters available on the market and has an incredibly high capacity and a lifetime of 50,000g or five years. The UC-200 is designed for use with municipal water and not water from private well systems. It is an under sink water purifier and not an under sink water softener, so if that is what you’re looking for, this is not the choice for you. Unlike other systems with carbon only filters, this one is bacteriostatic and immune against mold or bacteria. The setup process is easy when you use the provided manual and watch a few short videos online. You are not required to have a separate faucet above the sink, and you can use the one you already have, which makes everything much more manageable.

CuZn UC-200 Reviews

Aside from the praises heard about the system itself, this company also provides excellent customer service. One customer went to the hardware store to get extra parts to fit the system to their sink, then later contacted customer service who offered to make a custom filter based on the dimensions of the sink and covered the cost of what the customer spent at the store. This is exemplary customer service that I don’t see very often. People say that the water tastes exactly as it should with no extra flavors. If your normal water used to smell heavily of chlorine, you will notice the difference in smell immediately.

Contrary to other kitchen water filters, this one has no impact on water flow, so your pressure will remain the same.

CuZn UC-200 Pros:

  • No leakage.
  • Easy setup.
  • Affordable.

CuZn UC-200 Cons:

  • Heavy.

Frizzlife Under Sink Water Filtration System

The Frizzlife MK99 under sink water filtration system includes a two-stage water purifier with 0.5 micron, which has a unique technology that removes contaminants while leaving in all essential minerals. It fits both ½” and ⅜” water lines, eliminating the need for extra adaptors and plumber services. Using the quick change twist-in installation design only takes a few minutes to install the system or replace the filter. It has a unique auto shut off design, so you don’t need to shut off the water supply whenever you are working on the filter cartridge replacement. You can order one of these without a faucet and set it up to your existing one, or get the faucet. If you opt for the faucet, then keep in mind that you will have to drill a second hole in your sink.

Frizzlife Reviews

Many customers say this has been the best kitchen upgrade they have made in some time. Chlorine-tasting and smelling water tastes perfect and is odorless after using this filter. The water comes out crystal clear and without flakes. The installation has been relatively easy and usually takes only one attempt. There have been almost no experiences of leakage. People are pleased with the fact that it also comes with a longer stem for thicker countertops. If you are worried about it fitting, then you shouldn’t as it is compact and small, so you definitely have the space for this under sink filtration system. There have been no decreases in water flow or pressure after installing this filter. Sometimes, the tools or parts have arrived faulty due to breakage during shipping and rough handling, yet their customer support has provided all dissatisfied customers with replacement parts.

Frizzlife Pros:

  • Great customer service.
  • Cheap to maintain.
  • Compact.

Frizzlife Cons:

  • Faucet slightly flimsy.

Whirlpool WHER25 Under Sink Water Filtration System

The Whirlpool WHER25 water filtration for kitchen sink uses reverse osmosis to filter tap water into bottled quality water. It reduces all chlorine taste and odor, lead, chemicals, and dissolved solids that are present in your unfiltered tap water. Their ultra ease technology allows for easy filter changes. The Whirlpool 3-stage system is very compact and saves you space, and has fewer filters to replace. It requires you to purchase lithium metal batteries, which are not included in the kit.

Whirlpool WHER25 Reviews

It has a straightforward set-up process that won’t require any extra professional help. A cool feature that customers seem to like is the EZ-Change indicator light that will notify you when it is time to change the filters. A filter usually lasts 5-6 months and sometimes longer. Customers like that the filters easily screw off, so they don’t need any tools to change them out. For its affordable price, it is highly durable.

One customer who has installed a unit in 2008, experienced leaks only in 2019. They purchased a replacement unit for under $150, which included three filters and took only 15 minutes to install, and are consistently very satisfied with the quality of the water. The only customers who have experienced leaks are those who have had this system for multiple years. One of the complaints noticed is that this system fills a gallon very fast, then it slows down a lot and can only fill a gallon again after some time, so if you consistently require a large amount of water, this is not the optimum choice for you. You can also taste and see the clear difference between tap water and filtered water.

Whirlpool WHER25 Pros:

  • Simple assembly.
  • Budget-friendly.
  • Easy to maintain.

Whirlpool WHER25 Cons:

  • Low filtration capacity.

Under Sink Water Filter Buyer’s Guide

Is it good to drink sink water?

Generally speaking, water from the faucet is safe to drink in most parts of the United States. According to the Environmental Protection Agency, all drinking water should reasonably be expected to contain small amounts of contaminants. The EPA sets legally enforceable standards that are meant to limit the levels of pollutants from industrial chemicals, bacteria, and other potentially harmful sources in drinking water.

There is a second set of non-enforceable guidelines for contaminants that may cause cosmetic effects like skin or tooth discoloration, or contaminants that may change the taste, odor, or color of drinking water. It is not mandatory that water systems comply with NSDWRs, so water may not pose a direct health risk but might smell or taste bad. If your sink water is unclear, contains flakes, tastes metallic or rancid, and has an odor, then you should definitely consider investing in an option from this list of the best under sink water filtration systems.

How to install under sink water filter?

The necessary steps to installing an under sink water filter are almost the same, yet some directions are specific to the filter type. Before setting up the filter, read the manual carefully, and search for videos on how to set it up.

Step 1: Drill a hole in your sink. Check if you maybe have a pre-existing hole in your sink
Step 2: Split your water line. After the hole is drilled, run the waterline and end of the filters faucet through and secure it with a nut. Then you must plug the water line into the water filter.
Step 3: Install your water filter. After you tap into the cold water, you should attach the water line to the splitter and plug the other end into the filter. Then you secure the water filter to the wall or the side of the cabinet.

How often to change water filter under the sink?

Filters need to be changed punctually, or else the contaminants will clog the filter, leaving no space to capture any other chemicals or particles, and these will start to flow out along with the water. There is no standard amount of time after which a filter should be changed as it varies, depending on a few things.

Under-sink water filter reviews and manuals will specify how long filters have lasted, but it is also specific to your area, how contaminated the water is, and how much water you consume.

How to replace under sink water filter cartridge?

– Shut off the water supply.
– Open the faucet and drain the water.
– Open the casing with a screwdriver or the provided tool.
– Remove all the filters.
– Clean out the casing.
– Put in the new filter.
– Close the casing.
– Check for leaks by turning on the water.

Make sure to change all the filters at the same time, even if some might not look worn out.

Author: Mark Miller

I have graduated The Culinary Institute of America in 2013 and became a chef assistant in one of New York city restaurants. As a talented young cook I began to move up the career ladder – just a few years later I'm worked as a chef in the most prestigious restaurants. Early in my career, I attended many workshops and seminars in Europe and the United States. The training took place at Michelin 3*-4* restaurants and cooking schools.