The Best Under-Sink Water Filters for Better Tap Water

Hello, my friend, hello again; today we come together to talk about The Best Under-Sink Water Filters for Better Tap Water and hope the blog can help you.

Tired of refilling pitchers or buying non-eco-friendly plastic bottles? Get clean water right from the tap with an under-counter filtration system.

Editor’s Note: Testing in progress! We’re currently testing 4 new models. Stay tuned for new, hands-on reviews of our top picks. 

Common tap water may contain contaminants due to the pipes it travels through and chemicals used in the municipal filtration process. If your family wants easy access to a filtered tap water supply for daily drinking and cooking, an under-sink water filtration system is a convenient solution.

Countertop water filters can be effective, but they may also be a bit of an eyesore and take up valuable counter space. Under-counter models keep the mechanics out of sight while providing filtered water right at the kitchen sink. The best under-sink water filters have multiple levels of filtration to offer clean tap water with no hassle.

1. BEST OVERALL: iSpring RCC7P-AK 6-Stage Reverse Osmosis System
2. RUNNER-UP: Express Water RO5DX Reverse Osmosis Filtration System
3. BEST BANG FOR THE BUCK: Waterdrop 15UA Water Filter System
4. BEST TANKLESS: Waterdrop Reverse Osmosis System
5. BEST FAUCET OPTIONS: Aquasana AQ-5200.62 2-Stage Water Filter System
6. BEST FOR ALKALINE WATER: Apec Water Systems ROES-PH75 Water Filter System 
7. BEST FOR WELL WATER: Home Master TMHP HydroPerfection RO System
8. BEST W/O SEPARATE FAUCET: CuZn UC-200 Under Counter Water Filter
9. BEST FOR BATHROOM: Frizzlife Under Sink Water Filter System

How We Chose the Best Under-Sink Water Filters

After evaluating the key aspects that go into under-sink water filtration—the amount of contaminants removed, physical size of the system, and number of filtration stages—the above list reflects our thorough research into the most suitable products across different price points and filtration types.

We made sure to include several options for under-sink water filter systems that can filter municipal water, well water, and alkaline water to remove over 1,000+ contaminants including chlorine, heavy metals, and bacteria. Some of these under-sink water filters come with countertop faucets, preventing the need for a separate (and potentially more costly) purchase. Select sink filtration systems also stood out for their water-saving designs and built-in pumps that improve water pressure as well as replacement filters.

Our Top Picks

The best under-sink water filters will provide effective filtration, access to ample clean water, and a relatively easy installation. The following under-sink filter systems include these and other features if you’re looking to add the convenience of filtered water at the kitchen sink.

Best Overall

iSpring RCC7P-AK 6-Stage Reverse Osmosis System

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Product Specs 

• Type: Reverse osmosis system
• Capacity: 75 gallons
• Flow rate: 75 gallons per day

Pros

• Highly efficient system capable of removing 1,000 contaminants through 6 filtration stages
• Built-in electric booster pump maintains performance regardless of fluctuations in water pressure
• Sixth reverse osmosis filter provides alkaline remineralization for natural water taste
• Installation is made easier by the inclusion of both written instructions and a useful video

Cons

• Requires considerable under-counter space and is expensive compared to other water filtration systems

Talk about thorough: This reverse osmosis (RO) system from iSpring removes up to 99 percent of more than 1,000 contaminants found in tap water, including lead, arsenic, chlorine, fluoride, and asbestos. Its impressive six stages of filtration include sediment and carbon water filters to remove large contaminants and protect the reverse osmosis membrane from chemicals like chlorine and chloramines.

The reverse osmosis system’s filter removes contaminants down to 0.0001 microns so that only water molecules can fit through. An alkaline remineralization filter restores healthy minerals lost in the filtration process, and the last filtration stage gives the water a final polish before being delivered to the included brass faucet, which has a sleek brushed-nickel design.

An electric pump boosts the water pressure so there is less waste during the filtration process, with a ratio of 1 filtered to 1.5 wasted gallons. The water filters need to be replaced every 6 months to a year. Installation can be done by the user with the help of the company’s written and video guides. Live phone support is available for those who run into any problems or have questions not covered by the provided guides.

Get the iSpring under-sink water filter at Amazon, Lowe’s, The Home Depot, or Overstock.

Runner-Up

Express Water RO5DX Reverse Osmosis Filtration System

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Product Specs 

• Type: Reverse osmosis and carbon filtration
• Capacity: 4 gallons
• Flow rate: 0.8 gallons per minute

Pros

• A competitively priced system that comes with a set of replacement filters
• Highly efficient 5-stage filtration that removes up to 99.99 percent of contaminants
• Leak detection system shuts off water flow in the event of a fault
• Can produce up to 50 gallons of filtered water per day

Cons

• A few owners report leaks, though it’s difficult to know how well they were fitted

Thanks to a collection of easy-to-install fittings and upgrades, such as ultraviolet, alkaline, and deionization filters, this reverse osmosis system with five stages of filtration is an excellent solution for just about any home that uses municipal water.

In this system, the water first passes through a sediment and two carbon filters before reaching the RO membrane, which removes the finest contaminants. The last stage features a third carbon filter, which aims to eliminate any lingering toxins.

The system is budget-friendly and comes with four replacement water filters, which need to be changed twice a year. One drawback with this system is there is no pump, so water waste comes out to about 1 to 3 gallons.

Get the Express Water under-sink water filter at Amazon or The Home Depot.

Best Bang for the Buck

Waterdrop 15UA Water Filter System

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Product Specs 

• Type: Carbon filtration
• Capacity: 16,000 gallons
• Flow rate: 0.75 gallons per minute

Pros

• A budget-friendly system that uses effective 3-stage carbon filtration
• Removes contaminants and heavy metals to NSF/ANSI 372 standard
• Compact design ideal for cramped under-sink spaces and RVs
• Quick 3-minute installation process with simple push-to-connect fittings

Cons

• Does not come with a separate faucet and may impact water-flow rate

Water filtration needn’t cost an arm and a leg, and installing a filtration system doesn’t have to take up precious time. This Waterdrop product is among the most affordable under-sink water filter systems and can be installed in just 3 minutes, making accessing clean tap water a cinch.

This model is also a great option for shoppers who don’t have the cabinet space for a larger water filtration system. The small attachment connects directly to the cold-water line and dispenses carbon-filtered water from the main faucet, reducing odor and pollutants such as chlorine, sediment, rust, and other heavy metals. While it doesn’t eliminate as many contaminants as an RO system, it does retain healthy minerals, like calcium, potassium, and magnesium.

Waterdrop boasts an easy installation with its push-to-connect fittings and a twist-and-lock system that makes changing the under-sink filters easy. For simple upkeep, each filter has a maximum service life of 24 months or 16,000 gallons.

Get the Waterdrop 15UA under-sink water filter at Amazon, Lowe’s, or The Home Depot. 

Best Tankless

Waterdrop Reverse Osmosis System

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Product Specs 

• Type: Reverse osmosis
• Capacity: 400 gallons
• Flow rate: 400 gallons per day

Pros

• Extremely effective 8-stage filtration process removes a huge range of contaminants
• Built-in water pump reduces water waste and maintains water pressure
• Smart faucet gives instant sink water-quality feedback and warns when filters need to be changed
• A more compact design than many similar RO systems frees up under-counter space

Cons

• The advanced technology is reflected in a higher ticket price than most competitors

Another great option from Waterdrop for kitchens with limited under-sink space, this sleekly designed tankless RO system has a compact footprint without skimping on special features. New technologies make for a smart operation. An internal pump offers faster water flow and less waste with a 1-to-1 ratio of filtered to wastewater, while a leak detector cuts off the water in the event of leaky pipes.

Three under-sink filters provide multiple levels of cleansing, including sediment and carbon-block filters, an RO membrane, and an activated-carbon-block filter, which uses activated-carbon granules made from natural coconut shells to improve water taste. A helpful indicator light will change colors when it is time to replace the filters. Use the included manual or online tutorial to help with installation. Note: The system must be flushed out for 30 minutes before use.

Get the Waterdrop reverse osmosis under-sink water filter at Amazon, Best Buy, or Walmart.

Best Faucet Options

Aquasana AQ-5200.62 2-Stage Water Filter System

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Product Specs 

• Type: Carbon filtration
• Capacity: 500 gallons
• Flow rate: 0.5 gallons per minute

Pros

• Choice of 3 high-quality faucet finishes to suit a wide variety of decors
• 2-stage filtration system is capable of filtering 77 different contaminants and has a longfilter life
• Eco-friendly filters have simple twist action for easy replacement without disconnecting water
• Compact design requires a modest amount of under-counter space

Cons

• A number of leaks have been reported, and owners are critical of support

Shoppers interested in incorporating a new faucet with their under-sink water filter should consider this model from Aquasana. Available in three stylish finishes to match a variety of kitchen decors, the system has two stages of filtration and can remove up to 99 percent of 77 different contaminants, including lead and mercury, as well as 97 percent of chlorine and chloramines. The under-sink filters are made to be environmentally friendly with minimal disposable plastic parts.

Since this under-sink water system does not use an RO membrane, there is no water supply wasted, and the filtering process will retain healthy minerals. It has a filter life of around 600 gallons, which can last up to 6 months. Installation can be done by the owner with the help of a detailed manual.

Get the Aquasana under-sink water filter at Amazon.

Best for Alkaline Water

Apec Water Systems ROES-PH75 Water Filter System

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Product Specs 

• Type: Reverse osmosis
• Capacity: 75 gallons
• Flow rate: 75 gallons per day

Pros

• High purity filters safely raise alkaline levels in the water and neutralize acidity
• 6-stage filtration removes 99 percent of bacteria, viruses, cysts, organics, chemicals, etc.
• Comprehensive kit includes water tank and high-quality brushed-nickel faucet
• Leak-free quick-connect fittings and valve help simplify and speed up installation

Cons

• As with other multistage water filtration systems, it requires a considerable amount of space

While plain water is just fine for plenty of people, some prefer the taste and purported health benefits of drinking alkaline water. Thanks to a mineral cartridge that adds high-purity calcium carbonate back into the filtered water, alkaline water drinkers can now enjoy this higher pH beverage straight from the tap by using this filter from Apec Water Systems.

In terms of filtration, double-carbon blocks and an RO membrane work to eliminate 99 percent of more than 1,000 contaminants, including chlorine, fluoride, arsenic, lead, and heavy metals. A reliable choice, this under-sink filtration systemhas been certified by the Water Quality Association, which ensures high-quality water filtration products.

A sleek brushed-nickel faucet is included with the filter. Keep in mind that there is water waste to consider with this filter, as it has a slightly high 1- (filtered) to 3- (waste) gallon ratio. Videos and a manual are available for those who opt for DIY installation.

Get the Apec Water Systems under-sink water filter at Amazon,