WQA and NSF Certified Water Filters | All You Need to Know

Looking for an NSF 53 certified water filter? We discuss the different NSF and WQA standards and recommend some water filter systems that have these accreditations. We will discuss some NSF Certified Water Filters and help you understand better what to look for in a water filtration system from the certifications’ point of view.


Why Do We Need Certified Water Filters?

Water filter manufacturers are like any other companies trying to sell their products, and they are prone to exaggerations about their systems. The figures they give for water production rates and lifespans of filters are achieved under optimum conditions, and will often not match up with your experience.

However, the most important figures are those which concern a water filter’s effectiveness in protecting your water. Companies commonly boast of “99% lead reduction” or “95% of chlorine removal”, so how do we know whether to believe these figures, if others are sometimes fanciful?

Luckily, the Water Quality Association (WQA) and NSF International are at hand. These are independent organizations that test and certify water filter systems and components. Water filter systems that carry these logos are proven to deliver on their promises.

Today, we take a deeper look into what these standards mean and find out which are the best certified water filters.

NSF Certified Water FiltersNSF-certified

NSF International provides certification to prove that water filters remove specific contaminants to a standardized level.

So what does ‘NSF certified’ mean for a whole house water filter, a faucet filter, a water filter pitcher, and so on?

In a nutshell, an NSF certified water filter is one that…

  1. … is structurally solid.
  2. … is built from approved plastics and components that won’t leach into the water (like BPA plastic).
  3. … is built from materials that will last.
  4. … has approved labels that are 100% true.
  5. … has test results that are 100% facts.

One thing to look for with the NSF certificates is that sometimes they will only relate to specific parts of the water filter system or specific contaminants that they reduce. Sometimes water filter manufacturers imply that their systems are fully certified in every aspect, when in fact they only meet one specific safety standard.

There are many different NSF certifications. Today we will look at:

  • NSF 53
  • NSF 58
  • NSF 42
  • NSF 401

We will discuss each specific NSF safety standard, and what it actually means. We’ll also give examples of some of the best NSF certified water filters that meet each of these standards.

Before we continue, however, it is important to tell you a few words about the NSF certified water filters list. Here are the steps you need to take to learn if a water filter of your choosing – no matter the type of model – comes with an NSF certification:

  • Go to the NSF Certified Products and Systems page;
  • Type in the search bar your water filter’s manufacturer name/brand and press Search. The page will lead you to listings on that brand’s certified water filter systems.
  • Alternatively, scroll down the same page and reach the Drinking Water Treatment Units subcategory.
  • Click on the link to see the NSF certified water filters list (and manufacturers) in alphabetical order.

Now that you know where to look, let’s see how to “read” your water filter’s certifications.


NSF 53 certified water filters meet the minimum safety requirements to reduce specific harmful water contaminants. Here is what NSF International says about these standards:

NSF/ANSI Standard 53 for Drinking Water Treatment Units is the nationally recognized standard for evaluating and certifying drinking water treatment systems for the reduction of contaminants from drinking water. NSF/ANSI Standard 58 is the nationally recognized standard for Water Treatment Systems that use reverse osmosis technology. Water filters are tested and certified to NSF/ANSI 53 and 58 to ensure they reduce contaminants, including lead, per the requirements of the standards.

These contaminants include:

  • Lead
  • Cryptosporidium
  • Giardia
  • Volatile Organic Compounds (VOCs)
  • Methyl Tertiary Butyl Ether (MTBE)

The NSF 53 safety standard includes structural integrity, material safety, and contaminants’ reduction performance claims. It typically relates to water filters that use carbon absorption as a means of filtration.

The removal rate of water filters that meet this standard can vary. The NSF standard means that the water filter meets a minimum threshold. You would have to consult the filter’s performance datasheet to get exact figures.

NSF 58 is a safety standard for lead, and another common contaminant removal too. Instead of carbon water filters, it relates to water filters that use a membrane, like reverse osmosis systems (RO).

In our opinion, the best NSF 53 certified water filters are the following:


This certified water filter pitcher is one we speak very highly about in our guide on the best water filter pitchers on the market. It is an NSF 53 water filter that will remove lead (and other contaminants). It is also NSF 42 certified (more on that later) to remove chlorine.

It’s an impressive pitcher that offers a level of filtration that other jugs can’t match. It’s also a rare breed of water filter that will remove fluoride in water too. This means the filters are a bit more expensive than average. But if you’re getting standards 42 and 53 NSF certification and fluoride reduction then you can justify the cost.

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PUR-3-Stage-Horizontal-Faucet-Mount-Chrome-FM-9400BPUR-3-Stage-Horizontal-Faucet-Mount-Chrome-FM-9400BPUR 3-Stage Faucet Mount

This faucet-mounted filter meets NSF/ANSI Standard 53 for the reduction of contaminants such as lead. It’s a system that we highly recommend in our faucet water filter guide.

It’s another that is very competitively priced, and very easy to install and maintain. This is one of the cheaper NSF 53 certified water filters.

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Aquasana-AQ-RO-3.56-OptimH2OAquasana OptimH2O

This NSF 53 water filter from Aquasana has an amazing level of accreditation. It is tested and certified to meet standards 42, 53, 58, and 401. It’s the only water filter that I am aware of that can boast such a thing.

Meeting such a range of standards makes this one of the best NSF certified water filters around. It is also a rare reverse osmosis system, as it uses carbon filtration as well as the special membrane.

Being an RO system, this needs to be installed under the kitchen sink. The installation isn’t complicated, but it will require some DIY skills.

Reverse osmosis systems offer the most powerful form of water filtration available in the home.

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The NSF 42 standard relates to a water filter’s ability to remove chlorine from water. According to NSF International, the NSF/ANSI 42, 53, and 401 standards describe the aesthetic effects of water filtration systems. They certify that a product reduces a particular set of contaminants from drinking water (chlorine, taste and odor, chloramine, particulate, iron, manganese, zinc, and total dissolved
solids (TDS)). However, NSF 42 certification does not include the harmful chlorine by-products. Like many standards, water filters can meet or exceed this standard to different levels of effectiveness. It is a baseline of chlorine reduction.

When it comes to certified water filters, this is one of the best NSF 42 certified filtration systems out there:

Woder-10K-GenIIWoder 10K Under-Sink Water Filter

This under-sink water filter comes with a certification saying it removes significant amounts of lead and chlorine.

It’s installed under the sink but is quite simple to set up. It can last for 3 years before you need to change the filter, which makes it very easy to look after.

It also comes very highly recommended on Amazon. Moreover, this water filter also comes with a Gold Seal Certification awarded by the Water Quality Association.

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NSF standard 401 is a new standard that rates the ability of a water filter system to reduce up to 15 separate contaminants. These contaminants have been found by scientific studies to be present in some drinking water.

It typically deals with unnatural chemicals like pharmaceuticals (prescription drugs, over-the-counter medication, etc.), BPA, herbicides, and pesticides. These are new and emerging pollutants that come from industrial processes and farming. This standard applies to carbon and RO water filter systems.

Aquasana-AQ-4000W-Countertop-Water-Filter-System-200pAquasana AQ-4000

This countertop water filter system actually meets NSF standards 401, 42, and 53. In doing so, it removes a wide range of harmful contaminants. If you want to learn more about Aquasana certified water filters, take a look at this listing!

Being a countertop unit, it is really easy to install and maintain too.

It comes with a very reasonable price and excellent Amazon reviews. If you want an Aquasana whole house water filter instead of a countertop one, read our Aquasana Rhino EQ-1000 review!

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WQA Certified Water Filters


The WQA offers a Gold Seal Certificate to show that a water filter system “is constructed or formulated from safe materials, the claims listed on the packaging are backed by test data, and the product will hold up under normal usage conditions.”

This means that if a model that has been WQA certified is stated as removing 98% of lead from your water, then you can have confidence in the fact that it will do exactly as it says. The WQA’s mission is to facilitate water quality improvement to enhance lives sustainably. The organization also advocates for the betterment of water quality and collaborates with NSF to offer users complete and updated guides on certified water filters.

If you want to learn whether or not your water filter comes with a Gold Seal Certification, follow these steps:

  • Go to the WQA search page;
  • Enter the name of the company producing your water filter;
  • If the website cannot find it, try the advanced search options.

An example of a WQA Gold Seal certified system is the iSpring RCC7-AK. If you check out the WQA listing, you will also find the iSpring RCC7 reverse osmosis water filter that we reviewed on a previous occasion.

ispring-rcc7ak-200piSpring RCC7-AK RO System with Storage Tank and Automatic Shut-off Valve

This RO system is WQA certified to remove a wide range of contaminants. RO is a very powerful method of water filtration, and this is one of the best models out there.

This particular system also has an alkaline filter that adds healthy minerals to the water. This means great-tasting, contaminant-free drinking water for the home. The system also has an NSF/ANSI 58 certification for reverse osmosis. Check out our iSpring RCC7-AK under sink reverse osmosis water filter review if you want to learn more about this product in case you need a powerful water filter to keep you safe and healthy.

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Certified Water Filters: How to Pick Certified Water Filters

I would recommend always looking for or asking about these water filter certifications. If a water filter system is certified in one of these ways then you can be assured of its quality, and relax in the thought that your drinking water is in safe hands.

However, none of these systems claim 100% contaminant rejection rates. The NSF & WQA standards mean that a system meets minimum requirements under independent testing. The manufacturers should have the actual documentation or results as public information. You should check this out to find out whether a certified water filter removes 99% of chlorine or 90%, for example.

An example of a performance datasheet for the Aquasana AQ-4000 that we mentioned earlier can be viewed here. It shows the level of rejection for each specific contaminant, and an overall pass/fail result.

Notes to Consider

Keep in mind that these two organizations are not the only authorities that provide independent testing. They are the most well known, and authoritative, but other ways exist. Some smaller manufacturers gain certification from smaller independent laboratories.

Most of the more well-known companies (APEC, iSpring, Aquapure, Aquasana, etc.) will always produce units that come with NSF/WQA water filters’ certifications. Be vigilant if you are on a tight budget, and make sure you see some form of certification/accreditation, be it from the big names or a smaller lab.

Another thing you should pay attention to is the search itself. For instance, the name of the producing company is not always the same name as the brand they sell their products under, so you have to refine your research. The search algorithms on the two websites do not always work great.

As an example, if you search for iSpring Water Systems, LLC on WQA, the search will not lead you to the RCC7 reverse osmosis systems. On the other hand, if you search for RO systems in the Advanced Search field, the website will list the two iSpring under sink RO filters together with the other certified brands.

Final Thoughts and Recommendations

If you’d like to know more about buying water filters then please read our guides for reverse osmosis and whole house water filters. If you’re not sure where to start, then our guide to choosing the right water filter is a useful resource too.

If you would like to keep up to date with the latest news and events in the water filter world, and also the latest on the environment and water pollution, then check out our Facebook page. There’s a link at the top of the page.

Hi I'm Jamie, teacher and owner/chief contributor at waterfilteranswers.com. We strive to bring you the most informative water filter reviews in the most intuitive and user friendly way. Besides offering advice on the water filter to suit your needs, we also post topical articles on water pollution and the environment. Stay connected and follow us on, Facebook, Twitter, Google+ and more!

  1. Is the Big Berkey countertop water filter NSF certified? Thank you very much.

  2. I was told that My non electric whole house water filtration system: Oroline Plus removes bacteria, heavy metals,
    chlorine and Floride.

    I was told by Cerrawater. com that their water pitcher takes everything out but floride. But, that it also puts in antioxidants and hydrogen which
    other filters do not do.

    Are either of these WQA or NSF certified?

    WQA does not have” Cerra water”
    on their list of water filtration systems listed. Perhaps it is because Cerra Water is a water pitcher water filtration system. I have been trying to
    find out what is in the filter of the
    Cerra water pitchers that puts
    hydrogen , and anti oxidanents back in the water. As the distributor claims any process that takes out Floride
    also strips the water of other good ingredients.

  3. Typo: ProLine Plus is my present non electric filter system.

  4. What do you think of BERKEY water filters?

  5. This was extremly helpful for me and my family. Thank you!

  6. Where is the whole list? Did you try zero water? What have you tested. How do we know your tests are thorough and you have chosen multiple different filters? There is no list anywhere, no comparisons, seems like not a lot of effort went into writing this up.

  7. Where does it say that Aquagear is NSF Certified. Even their website does not show a certificate, and NSF’s list of certified filters does not include the Aquagear.

  8. How can I read the ‘water meter’ that came with my pitcher?

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