The 9 Best Water Filters of 2023

What to Look for in a Water Filter

Filtration Method

The contaminants that a water filter can remove will depend in part on what type of filtration method it uses. Some filters are designed to remove microbes like bacteria, some remove particulates like dirt and microplastics, some remove heavy metals, and some remove a combination. The following are common types of filters and the contaminants they typically remove:

• Activated carbon: Water is percolated through a mass of special carbon solids that adsorb (not absorb) sediment, some heavy metals, chloramines, volatile organic compounds, and other impurities. This method is typically used for under-sink and countertop filters. If your water supply has a serious heavy metal problem or needs to be disinfected before being safe to drink, activated carbon filters won't cut it, but they're suitable for your typical U.S. household.
• Reverse osmosis: Water is pushed through a semi-permeable membrane to filter out a broad spectrum of contaminants, from microbes to heavy metals to pharmaceuticals. Reverse osmosis is typically used for under-sink filters and whole-home systems, though there are some high-tech countertop R.O. water filters now on the market. One major critique of reverse osmosis is that it removes healthy minerals from water.
• Ion exchange: Water is filtered through ion-exchange resins, which are synthetic bead-like materials that swap the charged contaminant matter with charged ions. This method is typically used by under-sink filters and whole-home filtration systems to remove heavy metals and decrease the water's hardness.
• Mechanical filtration: This is the simplest method, in which water is passed through a mesh cartridge or filter that trap particles that are too large to pass through. This works well for sediment, but smaller contaminants like bacteria, heavy metals, and chlorine require more advanced filtration.
• Ultraviolet light: Water is exposed to UV light to deactivate organisms like bacteria and parasites. (It sounds like pseudoscience, but the light damages the nucleic acids of the microbes' DNA, rendering them incapable of replicating.) This method doesn't remove any particulates like sediment, chemicals, or heavy metals, but it can disinfect unsafe water for whole houses at a time.
• Electrodialysis: Electricity is used to split water molecules into hydrogen and oxygen, which kills pathogens. This is mostly used for very large-scale water filtration and requires a lot of electricity.

Purpose

Water filters can remove contaminants like heavy metals and man-made chemicals from your water. If you are on well water, have old pipes, or live in an area with unsafe drinking water, you may need a water filter to remove contaminants like lead or actual particles like sand.

If you are on city water, you can look at the annual water reports to see what kinds of contaminants are in that water. Even if your municipal water is safe, you may have old pipes that could be leaching contaminants into your water. Adding a water filter can help remove those impurities and is much more convenient than water delivery services. Filters certified to remove chlorine, for example, can also encourage hydration by making water more enjoyable to drink.

Independent Certifications 

Because effective filtration is so important (and because it’s so hard to actually be able to tell if it’s working), certification is one of the only ways you can actually be sure your water filter is removing the contaminants its packaging claims. The NSF is one certifying body—other certifications to look for are the American National Standards Institute (ANSI) and the Water Quality Association (WQA). There is no one-size-fits-all certification, so it’s important to know what you want removed from your water. For example, the NSF offers certification for removing a certain amount of chlorine and a separate one for removing lead. The more certifications a filter has, the more contaminants it can remove. 

Rick Andrew of NSF International cautions that you just need to make sure your filter is actually certified. Marketing jargon to look out for includes “filters to NSF standards,” which does not mean it has been independently tested. An earlier version of our list included several water filters that were removed based on similar language that made it unclear whether they were independently tested.

Capacity

You will want to consider your household’s water consumption when purchasing a filter. A smaller pitcher may be fine for a dorm or apartment, but for larger households or using filtered water for cooking, faucet or under-sink filters may make more sense. Refilling a pitcher doesn’t take a huge amount of time, but if you need to do it several times a day, it can be a pain.

Filter Replacement

Filter cost and replacement frequency is another thing to consider. A water filtration system is only as good as its filters, so be sure to factor in their price, availability, and frequency of needing to be replaced. Some filters require their inserts to be replaced every couple of months, whereas some types can go a year or so before they need to be replaced. Make sure to pay attention to the manufacturer's instructions, since neglecting to replace a filter can result in a drastic drop in its effectiveness.

Cost

Water filtration systems can cost up to thousands of dollars, while smaller pitchers can go for around $20. You can get an affordable water filter for personal use without spending much, but make sure to look for certifications. Also, consider the cost of the water filter and how often it will have to be replaced when deciding what you want to spend. 

Types of Water Filters

When we think of water filters, a pitcher is the first thing that comes to mind, but filters can be used at almost every point of water's journey through your home. 

Whole-Home Systems 

Whole-home systems filter all the water coming into your home. The most common kind, says Andrew, "is a water softener that will help remove minerals and 'soften' your water." Since hard water is bad for pipes and water fixtures, a whole-house filtration system makes the most sense. Because this type of system filters water for the whole house, it's often expensive and time-intensive to set up. 

There are two reasons to get a water filtration system, explains Andrew. For drinking water in the United States, it's more likely that you’ll want a filter to improve taste or remove hard minerals and protect your pipes. Hard water (i.e., water with high mineral content) can damage pipes and water fixtures with buildup.

Under-Sink 

If you are filtering for contaminants or taste in your drinking water, a point-of-use filter is also an option. These can be filters that attach to the sink or under the sink where you get drinking water. Andrew emphasizes that whole-house filtration, unless you are on a well, is generally only for softening water, and that these point-of-use systems are sufficient if you’re filtering out contaminants. Under-sink filters are often easier to install than whole-home systems, but are more expensive than faucet attachments or pitchers. 

Faucet Attachments 

Like under-sink filters, faucet attachments offer instant access to filtered water at a place where you would be getting drinking water, such as the kitchen sink. These filters can typically be attached to most standard sinks, though they won't work with some other sink setups, such as a pull-down faucet with a spray nozzle. A faucet attachment will typically allow you to filter only the water you want to drink and let unfiltered water come through for things like washing dishes. If you are only filtering to improve taste, this should be sufficient. This type of system also puts less pressure on the filter by only filtering the water you need. 

Pitchers

Pitchers don’t offer the convenience of a sink filter because they need to be refilled, but Andrew says, "Some people prefer pitchers because they allow you to chill filtered water, which can make it more enjoyable to drink." It’s also the easiest to set up. Furthermore, if you are only filtering water for taste, you may find a faucet filter to be bulky and unnecessary while you do things like wash hands or dishes at the sink. Again, this comes down to preference, and both faucet attachments and pitchers are capable of filtering out contaminants. 

Countertop 

Countertop water filtration systems work similarly to faucet filters by diverting water from the sink into a filtration system with its own tap. Other countertop filtration systems need to be filled, acting like water coolers, and these can be bulkier than pitchers but require less frequent refilling. They do offer the advantage of allowing you to place filtered water anywhere in your home, away from a water source. 

Bottles

Special water bottles can filter water as you fill the bottle or drink, and they can be certified by the NSF and ANSI. Water bottles can be a great option if you want to drink filtered water on the go, and they're a great alternative to buying bottled water. However, certain filter bottles are only designed to remove contaminants from treated municipal water, so if you want a water filter for hiking or traveling in places without clean drinking water, you’ll need to be extra sure that the filtration system you're buying can remove bacteria and other organisms. 

While filters of all types can do a great job of removing contaminants, Andrew says, "No filter can actually remove all contaminants." Any filter that claims it can remove all or 100 percent of contaminants is misrepresenting itself, and no certifying body would verify those claims. "The technology just doesn’t exist," Andrew says. 

Brands

Brita

Nowadays, the term “Brita pitcher” has basically come to mean a filtered water pitcher. Brita’s filters all come with NSF certifications, and its pitchers are popular for their ease of use—drop a filter into the pitcher, and you’re good to go. Brita also offers a wide array of pitchers and filtration systems, including faucet filters and water bottles. Brita does not offer under-sink or whole-home filtration systems, however, and not all Brita filters are created equal. Depending on what you want filtered out of the water, make sure to check for those certifications. 

PUR 

PUR and Brita offer very similar products: basic filters that remove impurities for taste as well as mercury and other contaminants, and more expensive filters that can also remove lead and an even higher percentage of contaminants. PUR does offer the most certifications in its basic and more expensive filter. 

APEC

APEC offers a whole-house filtration system in addition to countertop filtration systems. The company’s whole-home systems are designed to remove things like odor and chlorine as well as minerals that can cause scaling on appliances. 

Maintenance 

Water filter systems, no matter the size or type, are not a one-and-done purchase. Filters don’t last forever; they'll eventually stop effectively filtering water. This can have two effects, Andrew says. For starters, the water can start to flow more slowly through the filter itself. More seriously, the filter can stop effectively filtering water, letting the contaminants stay in the water. Filters all come with a lifespan, from a few months to a few years. NSF certifications test to ensure that the filter can continue to remove contaminants for as long as its listed lifespan and even allow for a little bit of time on the end. 

“But at some point, it's just not going to work anymore,” Andrew says. Replacing your water filter per manufacturer instructions is just as important as purchasing the right filtration system in the first place. 

Accessories 

As brands try to set themselves apart in the filtration space, different accessories and add-ons have popped up, such as Bluetooth capabilities and sensors to monitor filter effectiveness. While these can be appealing bells and whistles, they are not necessary; if you follow manufacturer guidelines on replacing filters, for example, the sensor isn't needed. Ultimately, what matters is if the filter itself is capable of removing the impurities you want removed. 

FAQs

Do you need a water filter?

In short, it depends on your water supply. Some tap and well water supplies are completely safe to drink without filtering first, whereas some municipalities' water reports will show contaminants that you may want to filter out. Likewise, the pipes where you live may be old and prone to leaching contaminants like heavy metals into an otherwise-fine water supply. If you simply don't like the taste or smell of your tap water, a relatively inexpensive filter can help remove the chlorine and take care of the issue.

Which water filters remove the most contaminants?

While there are a variety of water filtration systems, no one type is inherently better (or worse) at filtering out contaminants. The same types of filters can remove different contaminants depending on how it was manufactured and certified. This is why experts recommend knowing what kinds of contaminants you want to be removed rather than simply looking for a filter that removes a lot of contaminants. If you are unsure of what is in your local water, you can get a water report. 

Do water filters remove bacteria? 

"NSF certifies filters that remove bacteria under a standard called P231," says Andrew, but those tend to be designed for activities like camping, when you may need to drink water from a stream. If you have specific concerns about bacteria in your drinking water, be sure to buy a filtration system certified specifically to remove bacteria. When in doubt, you can boil your filtered or unfiltered water as an added safety precaution against bacteria.

Can you filter any type of water? 

In short, absolutely. Water filters can be used for city and well water and on both soft and hard (high mineral level) water. Just be aware of what you are hoping to remove; a whole-house system specifically designed to remove minerals from hard water, for example, won’t work the same as a pitcher that removes chlorine for flavor. 

Do water filters remove fluoride? 

Yes, certain types do. If you have a preference, be sure to check your filter’s certification. 

Do water filters remove PFAS?

There are water filters that remove polyfluoroalkyl substances (PFAS) very effectively and filters that only have partial efficacy in removing them. If this is an area of concern for you, make sure you pick a filter that specifies removing PFAS.

How long do water filters last? 

Water filtration systems are only as good as the filters within them. Nearly all are designed to be replaced, and all certifications are done with the life of the filter in mind. So if your filter needs to be replaced every six months, NSF will test each filter to ensure a six-month lifespan. If filters are replaced regularly, the filtration system itself can last for years. 

Why Trust The Spruce Eats?

Donna Currie has lived and worked in areas of the country where the water was rated in the top 10 in the country…and she’s lived in areas where the water was decidedly unpleasant. Over the years, she’s tested a variety of models and done her research on the rest.

Commerce editors Taylor Rock and Fran Sales researched and contributed to this piece, as did Katya Weiss-Andersson, a writer and editor who has nearly a decade of experience as a professional chef.

Sources

Rick Andrew is the Director of Global Business Development of Water Systems at the National Science Foundation. He has 30 years of experience in preserving and maintaining clean drinking water and is responsible for NSF’s global sales and structuring of water-related programs.