The 6 Best Countertop Water Filters if the Fridge is Full

The Bottom Line

For fast filtration, minimal counter space, and easy-to-use design, the Aquasana Clean Water Machine checks all the boxes. But for budget, the Brita Hub Instant Powerful Countertop Water Filtration is a solid option at under $180. And it was the only machine we awarded a perfect score for ease of use.

Our Testing Process

To find the best countertop water filters, we evaluated nine different water filters–both faucet-fed and freestanding–using a predetermined methodology. We assessed each water filter based on five factors: water smell, water taste, ease of use, design, and the value for cost.

Expert guidance was also provided by Daniel L. McCurry, Ph.D., assistant professor, Department of Civil and Environmental Engineering, University of Southern California. 

We first examined unfiltered tap water, noting any cloudiness or smell. Then we compared the filtered water for each appliance, noting any changes in appearance or apparent taste. We evaluated the filtration performance further by timing each filter and ranking how quickly each appliance could filter a glass of water.

We also tested the assembly for each water filter and how easy it is to install faucet-fed units to common kitchen sink faucets. After each water filter was analyzed and ranked for each of the five testing categories, an average, overall score was calculated for each appliance.

What to Know About Countertop Water Filters Before Shopping

Freestanding vs. Faucet-fed

Like other appliances, some countertop water filters—especially those with digital screens—require electricity and have a cord or feature a rechargeable, removable cord. However, the most important factor to look for when shopping for a countertop water filter is whether or not the appliance is faucet-fed.

“They may be attached directly to a faucet to provide filtered water straight from the tap or come as a standalone dispenser with a reservoir that can be placed anywhere,” said McCoy. 

A faucet-fed filter means you don’t have to worry about refilling all the time, especially if the unit is small. But it’s not renter-friendly, as most recommend drilling a hole in your counter to feed the tube from under the sink to the appliance. (If you have an old in-sink soap dispenser you can sometimes bypass this process and use that hole.)

If you’re short on counter space and don’t have room right by your kitchen sink, a freestanding countertop water filter is more portable and practical. It’s also great to use on your nightstand if you’d like to have fresh water at night.

Dimensions

Depending on the design, countertop water filters can be as small as a toaster or as large as a mini fridge. We tested XL units at two feet tall but also tested super-small compact filters less than three inches wide. 

“It can vary,” said McCoy. “We carry a filter that is roughly 17 inches tall by 22 inches wide, and another that is much more compact at 11 inches tall by 3 inches wide. Both are great options. You really just want to consider the available space on your counter before choosing a filter.” 

Capacity

Beyond the dimensions, it’s important to look at the capacity of the water reservoir, as this will tell you how much filtered water the appliance can hold at a time. Sydney Evans, senior science analyst at the Environmental Working Group (EWG), said the water filters the EWG has studied range from 6 cups to over a gallon. 

It’s also important to note the filter capacity, which is often confused with the water tank capacity. The filter capacity indicates roughly how much water the appliance can filter effectively before it needs replacing.

And like the size of the water filter, the capacity varies widely based on the model and brand. “At Lowe’s, we have options ranging from this Home Master countertop filter—which has a 750-gallon capacity—to an APEC Water countertop filter with a 6,000-gallon capacity and a Mist countertop filter, which has an 8,000-gallon capacity,” said McCoy. 

And if you can’t find a specific number of gallons to watch for, some manufacturers will list the approximate filter capacity in amounts of time. And that can vary from six months to two years. 

Certifications

There are so many contaminants that show up in tap water, from lead to microplastics. Manufacturers make wildly different claims about what filters can reduce or eliminate. So, what’s the best countertop water filter for removing the most dangerous contaminants? And how do you know if a manufacturer’s claims are legit?

“You can look for National Sanitation Foundation (NSF) certification, which indicates the filter has been independently tested to verify, among other things, that it reduces the contaminants it claims to reduce,” McCoy says. 

Another common certification is from the American National Standards Institute or ANSI. However, Evans notes that not all filters work on all contaminants and a certification from NSF or WQA doesn’t mean that a filter can remove all contaminants.

“Some organizations like NSF and WQA provide some level of third-party verification that the filter actually meets the manufacturer's claims,” she said. “But it is important to find out exactly what those manufacturer's claims are when shopping for a water filter.” 

You’ll often see NSF or ANSI certifications listed with a specific number. Standards 42, 53, and 401 are considered the industry trifecta for removing weird tastes and odors (42), traces of medicines and other chemicals (401), and major health concerns (53) such as asbestos, lead, and mercury.

It’s important to look for these specific numbers if a manufacturer lists an appliance as being NSF certified to understand which contaminants the water filter will remove. 

Filter Lifespan

Like a water filter pitcher, the filter components don’t last forever. It’s important to consider how frequently you’ll need to replace a filter. Most of the countertop water filters we tested require replacement after six months, but some claim to last nearly two years.

It’s all dependent on how much water has gone through the filter, aka the filter water capacity, because the older the filter gets, the less powerful it becomes—especially for granular activated carbon (GAC) filters. 

“Over time, contaminants take up more and more space and these filters become less and less effective, and the filter cartridge needs to be replaced,” Evans says.

“Ion exchange resin, on the other hand, is a different kind of media designed to attract specific ions and exchange them for others. These resins also become saturated over time and need to be maintained. They are effective for some contaminants, and are commonly used as water softeners as well.”

Evans also noted that the lifespan of a countertop water filter cartridge can vary significantly depending on the brand, model, and filter type.

“It's important to note that in our study, we assessed each filter's performance after it had filtered 10 gallons of water. We did not evaluate how effective these filters were at the end of their estimated lifespan. It's reasonable to expect that filter efficacy may decrease over time, highlighting the importance of regular cartridge replacement to maintain optimal water quality.”

Ease of Use and Maintenance

The best countertop water filters should be as easy to use as a Keurig in terms of refilling water. We tested several different designs, noting which appliances were too big to fit under the sink and fill directly with faucet water.

For removable water tanks, we noted how easy they were to grip, fill, and pour. If low mobility is a concern, you may want to consider a faucet-fed filter to bypass carrying heavy water tanks. However, for faucet-fed filters, the initial installation can be a pain, and fitting a hose to your kitchen sink may not be ideal. 

Regardless of ergonomics, it’s important to note the specific cleaning instructions for the water reservoir and filtered water tank as they vary by brand and design. Several units that we tested require weekly cleaning for all water tanks. 

Other Countertop Water Filters We Tested 

RKIN AlcaPure Reverse Osmosis Countertop Water Filter

This water filter earned top marks as it’s ready to go straight out of the box. And while we loved the taste of the filtered water, the size of this appliance just isn’t practical for most kitchens. At about 2 feet tall, 2 feet wide, and 1 foot long, the unit is massive and takes up so much counter space.

You don’t even get that much water: the tank only holds about half a gallon of filtered water. So if one person in your household fills up a large tumbler, there’s only about a soda can’s worth of water left, which makes this a bad option for large families, or even couples who drink lots of water throughout the day. 

Santevia Gravity Water System with Fluoride Removal Filter

Assembly for this one is complex and one of us called it a total nightmare. Even worse: It takes so long for the water to filter. Add to the fact that this unit has ceramic pieces, mineral stones, and fluoride removal filters, which all require replacement at different times, and this unit quickly earned a high maintenance badge.

However, it may not be worth all the fuss because, despite all the fancy bells and whistles, it’s so bulky and just takes up too much countertop space. 

Your Questions, Answered

What are the advantages and disadvantages of countertop water filters? 

“Countertop pitcher and dispenser-style filters are generally easy to set up,” Evans said. “They can be more affordable on average compared to more complex systems like whole-house or under-sink water filters. They also don't produce any waste water like reverse osmosis systems do."

As for the cons, "They do by nature have a limited capacity and require refilling, they take up space on your counter, and filters have to be maintained and replaced for them to be effective.”

Another pain point for some is temperature. While the best countertop water filters save fridge space, they don’t chill filtered water. Most countertop water filters require room temperature water and keep filtered water at room temperature. 

What common contaminants do countertop water filters remove?

“Some are certified to simply reduce contaminants that affect taste and smell, while others can reduce contaminants that impact your health,” McCoy says. “The most common contaminants the countertop water filters can remove are lead, mercury, and chlorine, although this can vary based on the filter you purchase.”

Do countertop water filters connect to all kitchen faucets?

“Most of our countertop water filters connect to almost all kitchen faucets,” McCoy said. “But you should double-check the product specifications before purchasing.”

Most faucet-fed water filters come with multiple adapters to get the right fit and our pick for the best countertop water filter claims to work with 99 percent of all kitchen faucets. 

Can I connect a countertop water filter to multiple faucets?

If you’re hoping to use a countertop water filter at home as well as in an RV or another room in your home, double-check the installation kit for adapter accessories.

“Some water filters can be connected to multiple faucets, but it really will depend on the model you are purchasing,” McCoy says.

What is the healthiest way to filter tap water?

Is a countertop water filter better than a pitcher or a refrigerator filter? Depends. Are you more likely to remember to change a filter if you see the appliance on display on your counter? 

Because Evans says what matters most is how well you follow the instructions. “It's important to emphasize that the effectiveness of any filter relies on consistent and correct usage,” she says. "After all, the most efficient filters can only deliver their full benefits when used as intended.” 

Who We Are

Deanne Revel is an award-winning journalist and host based in Seattle. She covers home and design shopping, including the best deals and dupes, and did significant research on the best small slow cookers for this story. She also spoke to Sydney Evans, Senior Science Analyst at the Environmental Working Group, as well as Gary McCoy, a store manager at Lowe’s. 

What Is BHG Recommends?

Next to all of the products on this list, you may have noticed our BHG Recommends seal of approval. Products that earn the seal have been put through rigorous testing to make sure they're worth a spot in your home. We buy most of the products we test ourselves, but occasionally we are provided samples by companies if buying isn't an option. In these cases, we use the same testing criteria we use to test the purchased products.