Shopping for a water filter can feel like a trip through the twilight zone. Trying to make sense of the technical jargon and sorting through manufacturers’ claims is frustrating, and if you’re like some folks, you’re ready to throw in the towel.
But improving the quality of your drinking water is one of the most impactful things you can do for your health, so we’re going to ease the confusion for you with our comprehensive buying guide plus a review of seven top-rated water filtration systems that are designed to mount under a kitchen or bathroom sink.
6 Top Rated & Reviewed: Under Sink Filters
- Best for well water: Frizzlife
- Best for existing faucets: CuZn UC-200
- Best for Apartments: Woder 10K-Gen3
- Best for Fluoride: Filtrete
- Best for Chlorine: APEC WFS-1000
- Best for Lead: Aquasana AQ-5300
#1. CuZn UC-200 Under Counter Water Filter – Best for existing faucets
CuZn’s UC-200 is the ultimate install-it-and-forget-it under sink water filtration system.
It’s a no-nonsense unit with a minimalist design — set it up under the sink in minutes and enjoy clean water for five years or 50,000 gallons with no costly cartridge changes.
- Works with any kitchen faucet
- Installs in minutes
- Comes with a 90-day satisfaction guarantee and 5-year warranty
- Exceptional customer service
Best For: Anyone looking for a maintenance-free budget friendly water filtration system.
- Activated charcoal filter media removes sediment, chlorine, pesticides, herbicides and more.
- A unique bacteriostatic layer reduces heavy metals and inhibits the growth of bacteria in the filter — all without a significant drop in water pressure.
- With no cartridges to replace, the UC-200 is maintenance-free and has one of the lowest total costs of ownership on the market.
- CuZn isn’t a household name, but it should be — this is an excellent water filter. The UC-200 removes increasingly common city water contaminants, like lead and pesticides, as well as chlorine.
- Its total capacity is enormous — 50,000 gallons — and it’s one of the few filters you can install and not think about for five full years.
- But if you’re worried about lead, it removes slightly less than other models — 98-percent versus 99.9-percent.
- The difference is small, but because lead is highly toxic, especially to children, it’s large enough to matter.
- If your water isn’t at risk for lead contamination and you want a long-lasting, hassle-free filter that makes water taste great for the lowest possible price, this is one of our top picks for best undersink water filter.
- we like that CuZn under sink water filter requires no drilling to install.
- Designed only for use with biologically safe city water
Cuzn Product Updates:
- 36″ Stainless steel hoses included
#2. APEC WFS-1000 3 Stage Under Sink Water Filter – Best for Chlorine
Apec has been making filters for more than 20 years. This triple-stage system is made in the U.S.A.
it’s designed to remove sediment and chemical tastes from bacteriologically-safe city water.
- Affordable annual filter changes
- Easy to install
- Doesn’t remove healthy minerals
- Superior chlorine filtration
- Certified by the Water Quality Association
Best for: Those looking to improve heavily chlorinated city water.
- Three separate filters in heavy-duty housings remove particles like dirt and rust that make water cloudy and eliminate the heavy chlorine residue found in heavily-treated municipal water.
- Super-capacity cartridges last more than a year between changes, reducing maintenance costs, and the system comes with a compatible, 100-percent lead-free faucet.
- If your water tastes like it came from a swimming pool, APEC’s WFS-1000 has a triple-filtration system with two separate carbon block filters for maximum chlorine extraction.
- The initial cost is reasonable, it’s well-made, easy to install and filters need changing only annually.
- It requires a dedicated faucet — not my favorite feature — but it’s included, and like the CuZn, it doesn’t remove the healthy minerals I want in my water.
- If a heavy chlorine taste is your primary problem, the water from this filter tastes fantastic, but if you have kids and are worried about lead, other models may be a better investment.
- This system will not reduce water pressure.
- Installation is simple requires no drilling
- Does not remove lead or other heavy metals
Apec Product Updates:
- Apec now provides a 2-year extended warranty when you register your purchase.
#3. Aquasana AQ-5300 3-Stage Under Sink Water Filter – Best for Lead
This Aquasana 3-Stage kitchen sink water filter is NSF-certified to remove more than 77 common contaminants including chlorine, chloramine, pharmaceuticals, lead, heavy metals and chemicals like pesticides and herbicides.
- Removes chloramine without compromising filter efficiency
- The faucet is attractive and available in three colors
- Features a filter change alarm
- Cartridges are easy to replace
Best For: Those looking for a NSF certified filter that can handle most common city water contaminants should choose Aquasana.
- It doesn’t remove most microorganisms, but its catalytic carbon filter captures chlorine-resistant cysts like cryptosporidium and giardia — a noteworthy plus.
- Filtering capacity is 600 gallons between cartridge changes — roughly every six months — and as a bonus, a battery operated filter change alarm tells you when time to replace cartridges.
- Installation is easy, and the kit comes with a compatible faucet.
- It removes a broad range of contaminants including chloramine, a secondary disinfectant that select cities used in addition to chlorine.
- It has a high flow rate, a filter change alarm and an excellent sediment filter that reduces clogs and improves its overall efficiency.
- faucet that’s available in three colors.
- The filter change indicator battery will last up to 1600 hours.
- This system doesn’t remove any beneficial minerals like calcium, potassium and magnesium.
- Weak exterior housing.
- Limited customer service.
- Doesn’t remove fluoride.
Aquasana EQ 5300 Product Updates:
- Now comes in three faucet finishes.
#4. Woder 10K-Gen3 Ultra High Capacity Water Filter – Best for Apartments
The Woder Gen3 is designed to work with cold, biologically safe municipal water.
It removes lead, asbestos, chromium, mercury, sediment and volatile organic compounds and reduces the unpleasant taste and odor of chlorine while leaving in healthy minerals.
- Effortless installation
- High capacity
- Low total cost of ownership
- Selective filtration technology retains healthy minerals
Best For: Anyone looking for a long-lasting undersink water filter that can be setup in minutes.
- The kit contains everything necessary for installation. It sets up in minutes without special tools or drilling, and works with any faucet.
- The total filtration capacity is 10,000 gallons between cartridge changes and replacements are affordably priced.
- Woder makes a fine filter. Like the CuZn, it’s cartridge has an extended life span — 10,000 gallons or up to three years — and it capably removes most worrisome contaminants without affecting water’s mineral content.
- The flow rate is high at 2 gallons per minutes — almost double that of the Doulton — and it works with any kitchen faucet, even pull-outs.
- Installation is a breeze, cartridge replacements are inexpensive, and while it doesn’t last as long as the super high-capacity CuZn, it does remove more lead.
- Gallon for gallon, CuZn’s UC-200 is a little less expensive to operate, but both are about the same size, essentially hassle-free and perform like champs.
- If lead is your worry, the Woder is good choice. If cost and low-maintenance matter more, I’d opt for the UC-200.
- This filter will not reduce your water pressure.
- This can also be used with pull-out faucets.
- Lacks a filter change indicator
Woder Product Updates:
- Now offers two hose types: Steel or PVC
#5. Filtrete Advanced Under Sink Water Filtration System – Best for Fluoride
Filtrete filters are manufactured by 3M — a longtime leader in filtration technology.
The system is little more than a basic cartridge, so it’s low-profile enough for installation under kitchen and bathroom sinks with less-than-average space.
- Low-initial cost
- Fits in small bathroom cabinets
- Easy installation
- Can be used with any faucet
Best For: For anyone looking for a low-cost undersink water filter that’s NSF certified and made by 3M.
- It works with your existing faucet, and set-up takes less than 30 minutes.
- It has a 2000-gallon total capacity — an average family can expect about six months between filter changes.
- This system is recommended only for water that’s been treated for microorganisms.
- It removes sediment, rust, chlorine, lead and microbial cysts, but leaves in healthy minerals.
- If you’re on a budget, this Filtrete filter has the lowest initial cost to buy and is a pleasure to recommend with a few cautions.
- Among similar models, it has one of the highest micron ratings.
- That means it filters out more contaminants overall, but because of that, it also tends to accumulate more sediment and may reduce water pressure a little more than expected.
- It has a fairly low 1500-gallon capacity, and cartridges need to be replaced every six months but are reasonably priced.
- Cost shouldn’t be a barrier to clean drinking water — this model fixes that.
- It’s almost as cheap as a pitcher and costs less in the long run.
- Sign up for text reminders and Filtrete will let you know when it’s time to change to the cartridge!
- This system can be mounted vertically or horizontally without the need of a drill.
- This can be used as a secondary backup if you’re on a private well.
- Expect a decrease in water pressure
Filtrete Product Updates:
- No news, yet.
#6. Frizzlife Under Sink Water Filter System – Best For Well Water.
You can kiss bottled water goodbye with this inexpensive system from Frizzlife.
Each cartridge removes sediment, heavy metals, chlorine, VOC’s and other chemical contaminants from 1600 gallons of water.
- Doesn’t remove beneficial minerals
- Lower-than-average long-term cost of ownership
- Installation kit contains everything including plumber’s tape
- Comes with a two-year warranty
Best For: Those looking for a great way to remove harmful contaminants such as lead for a low cost.
- Kits come complete with a brushed nickel faucet and adapters for both 1/4-inch and 3/8-inch water lines.
- The cap has a unique auto shut-off feature that means your home’s water supply doesn’t need to be turned off for installation or cartridge changes.
- Replacement filters are among the least expensive in the industry despite their high quality.
- Frizzlife backs this unit with a 100-percent satisfaction guarantee.
- The filters can last one to three years, but in most practical circumstances, they should be replaced every six to eight months.
- FrIzzlife undersink filters are easy to replace and the process requires no tools, and with the auto shut-off feature, it can be done without turning off the water supply.
- With performance that’s similar to the Filtrete, the Frizzlife system is a single cartridge with a moderate capacity that comes in an all-inclusive kit that has both 3/8-inch 1/4-inch connectors and plumber’s tape!
- The cap that connects the filter to the cold water line features an automatic shut-off so cartridges can be changed without turning off the water supply — that’s convenient and less messy.
- Replacement cartridges are inexpensive and a breeze to replace.
- The system does, however, require the use of the faucet that comes with the kit, and although it’s very modern and attractive compared to similar models, it adds to the cost of the system and may not offer the look you want.
- If need a budget-friendly filter, but like your existing fixture, consider the Filtrete first.
- Won’t work with every faucet
Frizzlife Product Updates:
- No news, yet
Compare All 6 Under-sink Filters
(Mobile users: Swipe to scroll)
|Compare Brands & Models||#1 CuZn UC-200 Filter||#2 Apec WFS-1000 Filter||#3 Aquasana AQ-5300||#4 Wonder 10k-Gen3||#5 Filtrete Advanced System||#6 Frizzlife UnderSink Filter|
|Filtration Capacity||50,000 gal.||2,500 gal.||600 gal.||8,480 gal.||2000 gal.||1,600 gal.|
|Certifications||NSF Certified components||NSF certified components||NSF Certified 42, 53 & 401||NSF Certified 42, 372||NSF Certified 42, 53||NSF Certified 42, 53|
|Warranty||5-year||2-year||1 year limited||1 year||n/a||2 year|
Undersink Water Filter Buyer’s Guide
Undersink filters are less complex than costly whole-home systems, and unless you want to soften your water or need biological filtration, they offer a significant improvement in water quality and peace of mind without breaking the bank. Compared to using filtration pitchers or bottled water, an under counter water filter will save you lots of money. Here’s our buying guide to help you choose the best undersink water filter for your home.
1. What are the benefits of having an undersink water filter?
Municipal water is treated for harmful microorganisms and is biologically safe, but does that mean it’s as pure as it should be? Lead and other metals from aging pipes may be present, and new contaminants — like industrial chemicals and residue from discarded pharmaceuticals — have been discovered, but are not routinely tested for. A better under sink water filtration system removes these contaminants and more, and also makes water smell and taste better by reducing the chemicals that are used to make it safe to drink — like chlorine.
2. How does an undersink water filter work?
Undersink water filters connect to the cold water line under a kitchen or bathroom sink. These are known as point-of-use systems, and they treat only the water coming from one tap — unlike point-of-entry filtration systems that filter water to all faucets.
Water from the line enters the filter cartridge and flows through filtration media that traps contaminants — the type depends on the filter you buy — and then exits through the tap. It’s an easy, cost-effective way to filter the water you drink and cook with versus using a more complicated and costly whole home system.
3. What type of undersink water filter do I need?
The type of system you need depends on the contaminants you want to remove. If you’re on a city water supply, the top issues are chlorine, sediment, lead from aging pipes and industrial chemicals like pesticides. A water test for lead can tell you how much of a problem it is.
4. What to look for in an undersink filter system:
Several key criteria reflect how well a water filter will meet your needs: capacity, flow rate, micron rating and longevity. Here are their definitions and what they mean to you when you’re looking for the best under counter water filter.
- Capacity: This reflects the maximum number of gallons a filter can process before cartridges require replacement, but water with unusually high levels of contaminants make them less efficient over time, and it’s possible they’ll need to be changed sooner.
- Flow Rate: measured in gallons per minute — is the speed at which water moves through the filter media and out the tap. The filters on our list have flow rates from one to two gallons per minute maximum, but that doesn’t tell the whole story. Other factors such as the level of particles in your water, your home’s water pressure, cold water temperature and how easily a filter’s media clogs may reduce the flow rate to well below maximum. Always consider the big picture.
- Micron Rating: Think of water filters as strainers with holes measured microns — millionths of a meter. The size of the holes determine what size particles can pass through, and the smaller the micron rating, the more the filter removes. Micron rating is critical for filters that claim to remove bacteria, but is less significant with undersink filters. Filters with smaller micron ratings can remove parasitic cysts and finer sediment, but the trade-off is that they tend to clog faster.
- Longevity: A filter’s longevity is determined mostly by its capacity. The length of time between cartridge changes is determined by several factors including how contaminated your water is, but in general, the larger the system’s capacity is, the longer they last.
How To Install & Maintain Undersink Water Filters
Because replacements contribute greatly to a system’s maintenance requirements and the total cost of ownership, consider how many are in the system, how often they need replaced and what they cost before buying. To maintain efficiency, changing them as recommended is a must.
- If the filter sits in a bracket, attach it to the wall of the cabinet using a hand drill or screwdriver.
- Turn off water to the sink, disconnect the cold water supply line and attach it to the filter head.
- Using the included connectors, attach the filter head to the line that leads to the faucet.
- Turn the water back on and run it to check for leaks.
Installation is a little different for each model, but this is the typical process.
Changing filter cartridges may require a filter wrench — most kits include them. Others can be replaced without tools. Processes vary, but to change most filters:
- Turn off the water and put a towel or tray under the area to catch drips.
- Using your fingers or filter wrench, twist the cartridge off and away from its housing.
- Install a new filter and tighten it.
- Turn the water supply back on and test the filter for leaks.
Undersink vs. Countertop Water Filters
Countertop water filters do the job, but they have significant limitations. Most attach to your faucet with a hose, use valuable space on the counter, and they’re not particularly attractive. They have less capacity overall and usually won’t supply water fast enough for most families, and while they are marginally less expensive, as the cost of undersink systems comes down, the gap is narrowing, and that makes them even less of a bargain.
Undersink water filtration systems are an excellent value. They don’t remove every contaminant, and they don’t have the capability of comprehensive whole-home systems, but they’re convenient, affordable, simple to use and give you clean, great-tasting water that’s as good as bottled at a fraction of the cost and with far less environmental impact.