Best Reverse Osmosis Systems

So you’ve determined that a reverse osmosis system is an optimal solution for your home’s tap water.

Maybe you use a municipal water supply or well water and want to filter out inorganic dissolved solids. Or you might need a more effective RO membrane for bacteria and viruses. If you have well water, you might be tired of bottled water use for your drinking water needs.

Or maybe you are a chef or someone who wants the purest cleanest filtered water and realized that reverse osmosis is the most effective drinking water filter. 

You’ve come to the right place.

This post reviews the best home reverse osmosis systems you can place under your sink. That way, you get the purest filtered water for your drinking water and cooking needs. RO systems deliver the highest quality drinking water so that you can remove the use of bottled water.

Top 10 Home RO Water Filters 

#1 Waterdrop G3
  • Stages: 7
  • Output: 400 GPD
  • Remineralization: No
#2 Aquasana OPTIMH20 RO
  • Stages: 6
  • Output: 32 GPD
  • Remineralization: Yes
#3 Pelican 6-Stage
  • Stages: 6
  • Output: 20 GPD
  • Remineralization: Yes
#4 SoftPro Green
  • Stages: 5
  • Output: 75 GPD
  • Remineralization: No
#5 Home Master TMAFC-ERP
  • Stages: 7
  • Output: 75 GPD
  • Remineralization: Yes
#6 iSpring RCC7AK
  • Stages: 6
  • Output: 75 GPD
  • Remineralization: Yes
#7 Brondell RO
  • Stages: 4
  • Output: 57 GPD
  • Remineralization: No
#8 APEC Ultimate
  • Stages: 6
  • Output: 75 GPD
  • Remineralization: Yes
#9 Express Water R05DX
  • Stages: 5
  • Output: 50 GPD
  • Remineralization: No
#10 Home Master TMHP Hydro
  • Stages: 9
  • Output: 75 GPD
  • Remineralization: Yes

Reverse Osmosis Water Filter Reviews

There is no single best RO system. All 10 of the top reverse osmosis water system contenders have their share of benefits — and downsides. One of those downsides includes if your home’s water pressure is too low for you to use these filter systems. 

To pick the best reverse osmosis system for your home’s drinking water, you must figure out which system meets all your criteria. You also need to figure out what filtered water features you don’t need.

1. Waterdrop G3 RO

Why This Reverse Osmosis System is Our Top Pick:

The Waterdrop G3 RO filters are the most strong RO system on the list, providing an impressive 400 gallons of water per day (GPD). These gallons per day capacity is far more than even a large household usually needs.

This reverse osmosis water filter is also one of the few reverse osmosis systems which lack tanks and fit nicely under your sink. This tankless design means you can get water in seconds. That means you can fill a cup full of water in approximately 12 seconds.

Not to mention, these RO systems look fantastic with a compact design. You’ll also find that these reverse osmosis systems come with a dedicated faucet. This water filter price is affordable and certified by NSF. 

We highly recommend this filtration system as our top pick because of the overall high capacity, high-tech, and excellent design.

Stand-Out Features at a Glance:
  • 400 GPD water flow
  • Automatic flushing
  • DIY installation
  • Holiday mode
  • Low drain ratio
  • Smart technology on a dedicated faucet
  • Sound reminder
  • Tankless design
  • TDS display

Main Features & Benefits: 

The main benefit of the G3 filtration system is that it is tankless. This reverse osmosis water filtration system cleans your drinking water on demand. That means it can keep producing filtered water continuously, instead of needing to stop to refill a traditional reverse osmosis tank. That means the per day (GPD) output is more than 5x the average RO system with a storage tank.

The tankless design also prevents bacteria from forming in a tank and saves you 50% in under-sink space. Not to mention, the RO system features a sleek and modern design.

The G3’s water filtration is also top of the line, even with a tankless RO system. This reverse osmosis water system has been tested and proven to meet NSF 58 & 372 certifications to filter 94% of total dissolved solids

The water filter system contains 7 stages. Those include both carbon block filter and RO water filtration. That means it’s removing chlorine, taste and odor, sand, rust, solids, and other impurities. The RO system also reduces TDS to 94%, limescale, heavy metals, bacteria, viruses, and more than 1,000 other harmful water contaminants.
Lastly, it’s also a smart system. These RO systems have a LED ring on the faucet, which allows you to see the water filter status without looking at the device. It also has smart technology on the system, allowing you to monitor water quality and experience long-lasting results.

Who The G3 RO Systems Are Best For:

Suppose you’re looking for a high-quality RO system that doesn’t have many of its competitors’ drawbacks. In that case, the Waterdrop G3 filtration system is an excellent option. There isn’t any need to worry about wasting a significant amount of water, facing a complicated installation, experiencing a slow filtration rate, or a bulky size. 

Instead, the Waterdrop G3 is ideal for anyone looking for a tankless option featuring a strong filtering performance, simple installation, quick water filtering rate, lower water waste, smart leakage detection, and faucet featuring smart technology. These models also have a sensor alerting users of the unit’s filter life, TDS value, and water quality in real-time.

For the price point that the G3 is available, we believe this is the top RO system on the market for someone looking for a tankless, high-tech, under-sink RO system.

If you’re looking for the best, then this is the product you need to buy.

See our full Waterdrop Filters Review here for more information.


  • Tankless filter systems
  • 400 GPD capacity
  • Awesome looking filter design
  • Saves space under-sink
  • Smart filter technology
  • Filters 94% TDS and other water contaminants
  • Easy to install and has straightforward maintenance


  • Lack of water remineralization
  • Doesn’t offer alkaline water
  • Expensive
  • Requires electricity to operate
  • Users cannot place the unit on its side

2. Aquasana OPTIMH20 RO + Claryum

Why This Reverse Osmosis System is a Top Pick:

The Aquasana OPTIMH20 reverse osmosis system is one of our top recommendations. It is one of the only filters to pair reverse osmosis water filtration, claryum filtration, and water remineralization in one system. That means it filters all the contaminants from your water while also putting in healthy minerals that the reverse osmosis process removes.

Aquasana is the first in the industry to develop a reverse osmosis filtering product featuring remineralization technology. Using this groundbreaking technology, the Aquasana OPTIMH20 effectively removes 88 harmful contaminants, including fluoride. 

Aquasana RO

The reverse osmosis system is tested and certified to NSF/ANSI standards. This unit also filters five times more water contaminants than standard reverse osmosis systems. Not to mention that Aquasana is one of the leading brands, and you can rely on them to deliver.

Stand-Out Features at a Glance:
  • Filters out 88 contaminants and impurities
  • Eliminates 95% of fluoride and mercury
  • Eliminates 97% of chlorine and arsenic
  • Eliminates 99% of asbestos and lead
  • Ultra-fast performance
  • Easy twist-off carbon and claryum filter housings
  • 1 year RO membrane life
  • 1-year remineralization life
  • Six-month carbon and claryum filter life
  • 90-day guarantee
  • Two-year warranty

Main Features & Benefits:

Aquasana produces a top of the line RO system in the OPTIMH20 system. 

This RO system features a six-stage reverse osmosis water filtration process. These filtration stages include reverse osmosis, activated carbon blocks, catalytic carbon filters, ion exchange, 5-micron filtration, and water remineralization.

This system has been rigorously tested and certified to NSF/ANSI standards to filter 95% of fluoride and mercury, 97% chlorine and arsenic, and 99% of lead and asbestos. It filters 5x more water contaminants than a standard reverse osmosis system.

This system is also ultra-fast. That means it provides fresh, clean filtered water at a 0.05 GPM rate, translating to 720 GPD. It’s easy to replace the filters and pretty straightforward to install and maintain.

Who These RO Systems are Best For:

Compared to the Waterdrop unit, this system from Aquasana is an excellent option if you’re looking for a reverse osmosis system containing superior water filtration. This model includes water remineralization. That means the filter adds back in healthy minerals to your water, which standard RO systems take out.

The tankless design is also optimal for those who have minimal under-sink storage available. It’s also beneficial for those who want to have water on-demand from a high-quality point-of-use system.


  • Six stages of water filtration 
  • Certified to NSF/ANSI standards
  • Filters 5x more water contaminants than average
  • 0.05 gallons per minute flow rate (72 GPD)
  • Easy to install filter replacements 
  • Straightforward installation
  • Very affordable 


  • Not quite as powerful as Waterdrop’s gallons per day (GPD) output
  • Some consumers believe the water pressure is too low
  • There’s no automatic shut-off on the tank

3. Pelican 6 Stage RO

Why This Reverse Osmosis System is a Top Pick:

While maintaining its status in the water treatment industry, the Pelican 6 Stage RO system is compact and eco-friendly. This six-stage reverse osmosis model takes 95% of harmful chemicals and other impurities from your home’s water. There’s also a stage whereby remineralization occurs. That way, every member of your household can enjoy clean water from your kitchen’s faucet.

While filtering 50 gallons daily, this unit also produces a 30% higher flow rate than traditional RO systems. You’ll also find that this unit is NSF and ANSI certified to a standard of 58. These units also hold WQA Gold Seal Certification. As a product of the USA, this unit steps above its competitors regarding efficiency and maintenance. 

Pelican RO
Stand-Out Features at a Glance:
  • Three faucet finishes, including chrome, brushed nickel, and oil-rubbed bronze
  • Reduces water waste by 50%
  • Features the 6th stage of filtration to add minerals back into the water
  • Filters 50 gallons per day (GPD)
  • The filter delivers 30% more faucet water flow compared to competing models
  • No tools are necessary for maintenance
  • 4-stage membranes need changing every 18 months
  • 2-stage post filter needs changing every six months
  • This model is lighter and smaller than competing models
  • Limited one-year warranty

Main Features & Benefits:

During the first stages of filtration, this unit treats water for harmful pollutants. Those include arsenic, barium, cadmium, chromium 3 and 6, copper, fluoride, lead, radium, and more. During the last two stages, that’s when a carbon filter polishes the water and remineralization occurs. You should change the post-filter every six months. The four-stage membrane doesn’t need to change more often than 18 months. 

One of the downsides of every RO filter is that it wastes water. However, this Pelican unit wastes up to 50% less water than its competitors. This unit is also smaller than standard models. With its 14.5 x 12 x 14.75 inch dimensions, this unit can fit nicely under any small kitchen cabinet. When picking out which model you’d like to use, you’ll also find three faucet finish choices. Those include brushed nickel, chrome, and oil-rubbed bronze.

Who These RO Systems are Best For:

Suppose you are looking for an alternative to Waterdrop of Aquasana’s product and want a reverse osmosis system that is NSF/ANSI certified and includes water remineralization. In that case, this system from Pelican is an optimal choice. 

Many reviewers indicate that this unit is one of the leading models on the market for its price. Not only do these consumers report that it installs without trouble, but it also features a higher water flow. They also remark about how clean, fresh, and great-tasting their drinking water is now compared to before. 


  • 6 stage filtration
  • 50 GPD RO system
  • NSF/ANSI certified 
  • Filters 95% of water contaminants
  • Water remineralization
  • Compact and easy to maintain
  • A trustworthy brand made in the USA


  • Capacity per day is not as good as Waterdrop
  • Design isn’t great
  • Some consumers complained about leaking faucets
  • It’s priced higher than many competing models

4. SoftPro Green RO

Why This Reverse Osmosis System is a Top Pick:

Despite being effective at treating water for impurities, reverse osmosis machines are notorious for creating high levels of wasted water. That waste doesn’t always have to be the case, however.

Working as a family-owned business since 1990, Quality Water Treatment features the SoftPro Green Reverse Osmosis System. Using this unit means it can remove up to 96% of the impurities in your home’s water. However, while doing so, it only has a 1:1 waste ratio. That’s approximately two-thirds lower than competing models.

SoftPro Green RO

While starting with the 5-micron sediment filter, this unit features 5 stages in all. The remaining four include two coconut shell activated carbon blocks, an RO membrane, and a carbon post-filter. This unit eliminates up to 96% of arsenic, bacteria, chlorine, chromium, fluoride, heavy metals, lead, nitrates, and viruses. It accomplishes this goal while producing up to 75 gallons daily (GPD).

Stand-Out Features at a Glance:
  • Removes up to 96% of contaminants
  • 5 stage filtration removes over 1,000 contaminants
  • Features a 75 gallon per day filtration capacity
  • Wastes only 1/3 of the amount of water compared to competing models
  • Twenty-four faucet colors and styles, including contemporary, classic, and modern
  • Five-year manufacturer warranty

Main Features & Benefits:

This system filters 96% of contaminants found in residential tap water from your faucet with its 5 stage filtration system. That filtering process includes chlorine, lead, nitrates, chromium, arsenic, toxic heavy metals, organic impurities, fluoride, bacteria, viruses.

The 5 stage filtration system contains a sediment filter, carbon block filter, RO membrane filter, carbon post-filter, and RO storage tank.

This model can filter 75 gallons of water per day (GPD), which is pretty substantial compared to other reverse osmosis systems with a lower gallons per day (GPD) output.

This 5 stage reverse osmosis system also has a low one to one waste water ratio, which means it only wastes 1 gallon per gallon made.

A downside is that it does not include water remineralization. It also takes up a fair amount of space under your sink.

Who These RO Systems are Best For:

If you’re looking for a unit that isn’t a problem to install and comes with everything you need to complete the job, this unit tops the list. Each of the fittings you’ll find in the package are “quick connect.” That means all you have to do is push them in, and they’ll lock into place. This unit also includes a long-reach chrome faucet that compliments this model nicely.

Should you run into any problems when installing this unit, the Quality Water Treatment company has superior customer service. That means they strive to go above and beyond for each of their customers. In addition to this product having an excellent price, the company also offers a 60-day money-back guarantee. That, on top of the product’s five-year warranty, this is one that you should check out.


  • Filters 96% of water contaminants
  • 5 stage carbon block filter
  • 75 GPD filtration capacity
  • Low water waste ratio at 1:1
  • RO membrane


  • Average product not great
  • Not a well-known brand
  • Noisy when refilling the tank

5. Home Master TMAFC-ERP

Why This Reverse Osmosis Water Unit is a Top Pick:

Opting for the Home Master TMAFC-ERP under the sink reverse osmosis unit means your water goes through seven water treatment stages. Those stages filter, purify, and enhance your home’s water. This unit can take out up to 98% of the water’s impurities. Those impurities include chloramine, chlorine, dissolved solids, heavy metals, pharmaceuticals, and more. 

This unit also improves your water’s taste during its remineralization process. With its highly efficient design, you’ll find a non-electric permeate pump built-in that helps reduce wasted water by up to 80%. This pump also helps increase your home’s water production by up to 50%.

The Home Master company designed this unit to feature long-lasting filters. These filters are also easy to change and don’t require any special tools. All you need to do is make sure you’re changing them at least once annually or after 2,000 gallons pass through them. Because the design of these filters incorporates into the filter’s housing, that means the entire thing is disposable. In addition to helping to prevent leaks, this unit also reduces the level of biofilm and microorganism build-up. 

There’s a tank that stores up to 3.2 gallons, making its gallons per day (GPD) output low every day. The Home Master system is one of our top picks because of the high-quality filtration. This unit’s water remineralization function has a patented two-stage process. That means it adds back the healthy minerals in your water.

Stand-Out Features at a Glance:
  • Removes up to 96% of contaminants
  • 5 stage filtration removes over 1,000 contaminants
  • Features a 75 gallon per day filtration capacity
  • Wastes only 1/3 of the amount of water compared to competing models
  • Twenty-four faucet colors and styles, including contemporary, classic, and modern
  • Five-year manufacturer warranty

Main Features & Benefits:

Unlike some reverse osmosis systems, the Home Master provides full-contact purification. That is in conjunction with water remineralization, producing high-quality water with great taste.

The Home Master reverse osmosis water filter system eliminates up to 98% of chemicals, heavy metals, and sediment in your water while adding back in minerals.

Another advantage of the Home Master is its speed in dispensing water. That means that there’s no need to wait when you want a glass of water. The faster delivery is due to the permeate pump and the larger dispenser tubing, which is 3/8 inch rather than the standard 1/4 inch. The permeate pump also means that water wastage is just one gallon for every gallon of filtered water.

The system also has a modular design where the filter element and housing are an all-in-one assembly for quick and easy annual filter changes.

Home Master also has an excellent customer support team and a 5-year warranty on this product.

Who This Reverse Osmosis Filtration System is Best For:

The Home Master TMAFC-ERP system is an excellent choice if you want a standard water tank under-sink reverse osmosis system. It’s also optimal if you wish to water remineralization at an affordable price.

For those looking for a unit that produces water twice as fast as its competitors, this model is an optimal choice. Not only does it have that feature, but it’s also straightforward to install and doesn’t take up a significant amount of space. Consumer reviews also indicate that their drinking water tastes significantly better after installing this unit. 


  • Full contact purification
  • Water remineralization
  • Fast speed in dispensing water
  • Excellent customer support


  • The system makes noise when working
  • Takes up a fair amount space
  • There’s no UV light to eliminate microorganisms
  • Costs more than competing models

6. iSpring RCC7AK

Why This Reverse Osmosis Unit is a Top Pick: 

The iSpring RCC7AK is our #6 pick because it successfully eliminates up to 99% of over 1,000 impurities in the water. These impurities include asbestos, arsenic, bacteria, calcium, chlorine, fluoride, giardia, hormones, sodium, and more. You’ll also find that this unit can eliminate up to 98% of the water’s lead content. 

The iSpring unit features a five-stage RO filtration system that’s incredibly effective. This model also has the sixth stage for remineralization. During the first stage, there’s a polypropylene filter for removing rust, sand, and sediments. The second and third stage involves a carbon filter for removing chlorine and unpleasant odors and tastes. The fourth stage uses a membrane for removing up to 99% of the water’s impurities. During the fifth stage, the post-filter is available for removing any remaining tastes and odors.

The sixth stage is where this unit stands out. That’s when this model restores the water’s healthy minerals while simultaneously balancing alkalinity. The remineralization process uses all-natural stones to add calcium, magnesium, potassium, and sodium back into your home’s drinking water. In doing so, it produces more natural-tasting water.

Stand-Out Features at a Glance:
  • Exclusively designed six-stage alkaline remineralization filter
  • Protects against over 1,000 different types of impurities
  • 3.2-gallon pressurized tank with storage for 2.5 gallons of water
  • Produces slightly acidic water featuring pH levels of 7 or lower
  • Dedicated European-style faucet
  • Features 3 extra-long life pre-filters
  • Ultra-fine RO filter removes impurities down to 0.0001 microns
  • Simple DIY installation and has everything you need is inside in the box
  • 1:3 filtered water to water waste ratio
  • 30-day money-back guarantee
  • 1-year manufacturer warranty

Main Features & Benefits:

Offering an under the sink reverse osmosis system, the iSpring RCC7AK provides you with the benefits of reverse osmosis without taking up space on your kitchen counter. For many people, this is a selling point of the water filter system. If you have insufficient space under the sink, you might benefit from a countertop system.

Using six-stage reverse osmosis filtration, you can make sure that your water contains the lowest percentage of water impurities with the iSpring. This model can remove up to 99% of all pollutants, including fluoride. Plus, only the first five stages of filtration remove impurities: the last is for water remineralization. During the sixth stage of reverse osmosis, drinking water regains beneficial minerals for a high pH and better taste.

This unit produces 75 gallons daily, which is optimal for most families. This unit features a reasonable price point for one that contains the sixth stage of purification. Installation of the iSpring RCC7AK is easy, requiring just a couple of tools that you likely have already. In about an hour, installing the faucet and pressurized storage tank is possible. 

Lastly, it’s certified to NSF/ANSI standards for parts and contaminant removal.

Who This RO Water System Is Best For:

The iSpring system is a reliable water filtration pick. That is especially true if you are looking for a traditional tank reverse osmosis system by a reputable company that’s been in the water business for a while. It’s nothing spectacular, but it gets the job done for your tank under-sink drinking water needs.


  • Six-stage reverse osmosis filtration 
  • Filters 99% contaminants
  • Includes water remineralization
  • Easy installation


  • No permeate pump
  • Bulky and cumbersome
  • Some consumers complained about too much water waste
  • Other consumers reported low efficiency

7. Brondell H20+ Circle

Why This RO Water System is a Top Pick:

The Brondell H20 system made our list due to its efficiency and innovative technology, saving water. That innovation makes this unit ten times more efficient that its competitors. What’s surprising about this model is that its efficiency doesn’t involve using a permeate pump. Instead, the Brondell H20+ Circle features a patented smart valve, and it’s reservoir’s exclusive circular design increases its efficiency. 

Despite having these technological advancements, this unit has an incredibly small footprint. That means, after installing this unit, you’ll still have ample storage space beneath your kitchen cabinet. Because of its attractive design, many believe that it could have been a countertop unit.

This model features four separate filters for reducing the level of harmful impurities in your water substantially. Because of its non-electric design, this unit doesn’t require the use of any pumps. The system’s efficiency also involves saving an average of 2.1 gallons for every gallon of drinking water it produces. The refill rate for this unit is two times faster than competing non-electric models.

Stand-Out Features at a Glance:
  • Exclusively designed six-stage alkaline remineralization filter
  • Protects against over 1,000 different types of impurities
  • 3.2-gallon pressurized tank with storage for 2.5 gallons of water
  • Produces slightly acidic water featuring pH levels of 7 or lower
  • Dedicated European-style faucet
  • Features 3 extra-long life pre-filters
  • Ultra-fine RO filter removes impurities down to 0.0001 microns
  • Simple DIY installation and has everything you need is inside in the box
  • 1:3 filtered water to water waste ratio
  • 30-day money-back guarantee
  • 1-year manufacturer warranty

Main Features & Benefits: 

The Brondell H20+ Circle is quite efficient, wasting just 2 gallons for every one gallon of filtered water. Those gallons per day (GPD) is due to its flexible reservoir and patented smart valve, which helps remove back pressure in the reverse osmosis system.    

This system contains 4 stage filtration with a sediment filter, pre-filter, RO membrane filter, and post-carbon filter. It has certification by the water quality association (WQA) and meets NSF/ANSI standards for contaminant removal.

It’s important to note that this reverse osmosis water filter does not contain a water remineralization step. That means the water you receive can be pure with no contaminants, but it won’t contain healthy minerals.

It also stands out from the other reverse osmosis systems for its appearance: a black, rather than white, storage tank, which is very nicely designed and fits under your kitchen sink well.

Who These Filtration Systems are Best For:

Suppose you are looking for a decent black reverse osmosis system with average filtration and no water remineralization. In that case, this is a system to consider.


  • Sleek design
  • Saves water waste
  • 4 stage water filtration
  • Smart valve eliminates backpressure
  • NSF/ANSI certified for contaminant removal


  • Average water filter capacity  
  • Replacement filters are difficult to obtain
  • No water remineralization
  • Some consumers had difficulty fitting this unit underneath a standard sink
  • The faucet’s flow-rate seems lower than competing models

8. APEC Ultimate

Why This RO Water Unit is a Top Pick:

The APEC Ultimate made our list because it has an outstanding six-stage reverse osmosis filtration. We also like its water remineralization, WQA gold seal certification, and a quality business reputation. It’s a reliable reverse osmosis system.

Stand-Out Features at a Glance:

  • WQA certified and tested to eliminate up to 99% of contaminants
  • Large-capacity and long-lasting filters remove two times more contaminants.
  • A dedicated faucet that’s food grade and 100% lead-free
  • Stainless steel teeth on fittings create leak-free protection.
  • Five-year limited warranty

Main Features & Benefits:

An under-sink system, the APEC Ultimate features a pressurized tank that holds 4 gallons and requires 15 inches by 11 inches of cabinet space. These are around average requirements for an under-sink system.

One good thing is the APEC Ultimate is one of the most straightforward reverse osmosis systems regarding installation. Suppose you run into any problems during the installation process (or at any other time, for that matter). In that case, you benefit from the top-notch customer service from APEC water RO systems. After setting up the system, the only maintenance that these systems require is changing the filters once a year.

With six-stage reverse osmosis filtration, you know you’re receiving filtered water to the highest standards. The APEC Ultimate filters 99% of contaminants and solids as well as bacteria. The sixth stage remineralizes water with calcium and magnesium. That way, those minerals help you reach your recommended per day allowance of these minerals and enhance the water’s taste.

Who These Filtration Systems are Best For:

Overall, another solid choice if you don’t like our top recommendations. The system gets the job done well with a standard tank and faucet, but it doesn’t have a sleek design or outstanding features. 


  • Easy to install
  • Good customer service
  • 6 stage filtration that removes 99% of contaminants
  • WQA certified


  • Too much water waste
  • Some users report taste issues
  • Other consumers indicate the unit is difficult to install

9. Express Water RO5DX5

Why This Reverse Osmosis System Makes the List:

A budget system, the Express Water RO5DX5, provides high-quality filtered water at a discounted rate. Although it only features a 5 stage reverse osmosis process and no permeate pump, it effectively removes all types of contaminants from water coming out of your faucet.

Stand-Out Features at a Glance:

  • Five stages of water purification
  • Stage two and three feature carbon block and granulated carbon filters
  • Double-sealed filters preserve and protect your kitchen and the unit’s filters
  • Eliminates 99% of contaminants, including arsenic, bacteria, calcium, chlorine, fluoride, lead, nitrates, and more
  • Easy to understand and quick installation
  • Includes feed adapter and quick-connect adapter
  • Emergency leak stop detector that works by shutting off the water flow
  • Pre-filters need changing twice annually, and the rest need changing once per year
  • Labeled color-coded matched system for easy replacements
  • 1 year limited warranty

Main Features & Benefits:

Despite the system’s low price, the filters in the Express Water RO5DX5 are good caliber — it filters 99.99% of impurities. When you need to change the filters, the process is simple. Everything you need, including the filter wrench, is in the package.

Installation of the Express Water RO5DX5 is just as easy, thanks to the detailed instruction manual that lays out the easy-to-understand language steps. Plus, the filters are pre-assembled for faster fitting.

Lastly, the system is NSF/ANSI certified for contaminant removal.

Who These Filtration Systems are Best For:

If you are looking for a budget option, this system from Express Water is one to consider.


  • Removes 99% of impurities
  • Straightforward installation with pre-assembled filters
  • NSF/ANSI certified


  • No water remineralization
  • No permeate pump
  • Produces 3 gallons of water waste for each of the gallons per day (GPD) that it purifies
  • Some consumers reported that the connections didn’t come with their faucet upgrade
  • Other consumers indicate that this unit is difficult to install

10. Home Master TMHP HydroPerfection

Why This Reverse Osmosis System Makes the List:

The Home Master TMHP HydroPerfection is one of the few filters with a UV light. That makes it suitable for more water source varieties. The UV filter kills 99.8% of microorganisms that may be present in your natural water source. Thes reverse osmosis water filters also have nine-step filtration making it one of the most useful filters.

Stand-Out Features at a Glance:

  • Advanced filtering and purification stages eliminate 98% of contaminants, including chemicals, heavy metals, iron, and more.
  • The patented full contact technology adds minerals, like calcium and magnesium, twice during the filtering process.
  • The unit includes a UV filter for destroying microorganisms.
  • Easy to change and long-lasting filters that need changing once annually or every 2,000 gallons
  • This unit’s Fast Flo RO Kit increases the water’s flow rate by nearly double.
  • The unit’s efficiency and water pressure improve with the permeate pump.
  • Increases water production by approximately 50% and reduces waste by almost 80%
  • Five-year limited warranty

Main Features & Benefits:

This system comes with nine-stage filtration. Sending water through a total of nine stages (including an iron filter), you’d be hard-pressed to find a filtering system that removes more impurities. That makes it ideal for families concerned about water quality, especially households receiving their water from a well.

It is easy to change the filters — there’s no need for any tools. The system’s installation is also simple, provided you do have some DIY knowledge. It should take around an hour to fit the faucet and pressurized storage tank.

Even better, the Home Master TMHP HydroPerfection has a permeate pump, meaning it wastes minimal amounts of water. That means it’s just one gallon for every one gallon of filtered water. You’ll receive drinking water quicker as well, due to the ⅜-inch diameter tubing that allows for faster water flow rates.

Lastly, the Home Master TMHP HydroPerfection comes with a 5-year warranty, which is longer than most other reverse osmosis filter systems.

Who These Filtration Systems are Best For:

If you’re looking for a top traditional reverse osmosis system with a tank, then this system is one to consider. It has 9 stage filtration, which is one of the most effective on the market, and it wastes smaller amounts of water compared to some brands.


  • 9 Stage filtration
  • Easy to change filters
  • 5-year warranty


  • A UV filter is often unnecessary
  • Requires electricity to run
  • Bulky and cumbersome
  • The system’s lamp requires a 115v power connection
  • The RO membrane removes too many helpful minerals

A Buyer’s Guide to RO Water Systems

Now you know about the top reverse osmosis water filters, how do you choose the one for your home?

Before you start narrowing down your options, make sure that you clarify what a reverse osmosis system does. You should also understand why it is different from other types of reverse osmosis systems.

What Is a Reverse Osmosis System?

A reverse osmosis filtering system uses technology as water passes through an RO membrane. Reverse osmosis systems can remove between 95 and more than 99% of contaminants from water coming out of your faucet. A reverse osmosis membrane is more extensive than any other membrane filtration method, including ultrafiltration, micro-filtration, and nano-filtration. You should replace that membrane every two to 3 years.


The Basics of Reverse Osmosis Water Filter System

A reverse osmosis system is typically a “point of use” filter system, meaning installation occurs near a faucet. Most designs include an installation either on the countertop or under the sink. They have a dedicated faucet that delivers potable water for drinking and cooking. By purchasing an extra line, you can also connect your system to your refrigerator for the water dispenser or ice maker.

How a Reverse Osmosis System Works

A reverse osmosis filter works with a high-pressure water pump to increase the system’s salt side pressure. In doing so, that pressure forces water across the system’s semi-permeable reverse osmosis membrane. 

Between 95% and 99% of dissolved solids remain behind in the wastewater stream during that process. The amount of pressure to push water the unit requires depends on the feed water’s salt concentration. If the feed water contains a high salt concentration level, that means it needs additional pressure.

When water enters the system’s reverse osmosis membrane under pressure, its water molecules pass through a semi-permeable membrane. During that process, the water’s salts and other contaminants cannot pass through, making them reject and flow into the wastewater stream. Some refer to the waste water stream as the brine stream. 

That waste water flows down the drain and feeds back into the feed water supply. There are also situations when this brine water can recycle back through the system to help conserve water.

Learn more about how reverse osmosis works here.

What Contaminants Does the Best RO System Remove?

Reverse osmosis water is free from all contaminants that come out of your faucet and could be damaging your health, even substances that can cause cancer. Your water might contain contaminants like:

  • Selenium
  • Arsenic
  • Nitrates and nitrites
  • Phosphate
  • Fluoride
  • Bacteria
  • Viruses
  • Cysts
  • Metals like lead, chromium, cadmium, radium, barium, and sodium

How Are Reverse Osmosis Filters Different Than Regular Filters?

A reverse osmosis system has a more comprehensive filtration level than a standard water filter that uses just carbon filter cartridges and sediment filters. A traditional water filter usually removes taste, odor, chlorine, chloramine, and other organic compounds and bacteria.

A reverse osmosis filter is a bit more useful. The main reason is that these filter systems remove all the contaminants from the water listed above, plus the ones that a standard filter removes as well.

One thing to make sure that you keep in mind is that reverse osmosis filtration is exceptionally efficient. That means that these filter systems make water so pure that it could remove healthy minerals from drinking water coming out of your home’s water faucet. If having these beneficial minerals in your drinking and cooking water is essential to you, it’s time to buy a filter that includes water remineralization.

Lastly, it’s important to note that an RO filter’s use is mainly a “point of use” under the sink system with a dedicated faucet. If you are looking for a whole-house RO filter water installation, see our guide to whole house filters.

What to Look For in Your Reverse Osmosis Water System

Before picking the best system for your home’s water, there are a few criteria to consider.

Space Requirements

To start, you need to assess how much room you have under your sink and on your countertop. It needs to be sufficient for the filters, reverse osmosis components, and (in most cases) the tank. It may be that you need to rule out a countertop system or an under-sink water system for lack of space. However, most homeowners should free up enough room for these filter systems under the sink by merely moving things currently there.

Replacement Filters

Multiple filters are excellent for having cleaner water, but they also mean more maintenance and a high expense. Plus, you’ll need to keep a note of when it’s necessary to change each water filter. For this reason, it’s essential to choose the level of filtration you need.

Water Source

The next point we’re going to discuss in this guide is your home’s water source. You need to know if your water is coming from a city supply or if it’s well water. That way, you can figure out which system could remove the contaminants present in your water. You can find out what your water has in it by conducting a water test through a certified lab. That way, you know which contaminants you need to remove and which filter systems are ideal for your home.

Water Remineralization

Your water may currently contain a large number of healthy minerals that the system can remove. Suppose you want to regain these water minerals. In that case, you should pick a water system that offers water remineralization to add them back. The water remineralization step is usually the last in the filter process before water leaves the faucet. It also occurs after the water has gone through the reverse osmosis membrane every day.

Water Usage

Even if you choose the most efficient reverse osmosis filtration system, it can waste some water. If you live in an area where water is scarce, wasting water may not be an option. In this case, you should pick a filter other than reverse osmosis to purify your water. Consider looking for the RO system that wastes the least amount and still offers quality filtration.

Water Pressure

Most water reverse osmosis systems use water pressure to operate. Water pressure needs to be at least 40 PSI for the reverse osmosis filter process to work. If your home has low water pressure, find out if you can increase the pressure with a booster pump — some reverse osmosis systems even come with a permeate pump. 

Keep in mind that it’s impossible to increase water pressure in some homes. That means if you don’t have adequate water pressure, that makes a RO system an unsuitable choice.

How Much Does a Reverse Osmosis System Cost?

The price of an RO system typically ranges between around $200 to $550. In large part, the price depends on the quality and additional features of the reverse osmosis system. Most of our picks for the best reverse osmosis systems fall within the range of $200 to $600 for each model.

Water Efficiency Ratio of A Reverse Osmosis Explained

The level of water wastage to purify water determines the water efficiency ratio for these systems. The best reverse osmosis system uses a permeate pump, which lowers the waste water rate to 1:1 — one gallon of water wasted for every one gallon of filtered water. Without a permeate pump, a good ratio is 3:1. Anything lower than 4:1 is considered decent, but budget water systems could have a rate as high as 5:1.

Optional Accessories for Your Home Reverse Osmosis System

Many of the top reverse osmosis water systems come with additional accessories to improve filter efficiency and increase water quality coming out of your home’s faucet.

There are three main accessories that many reverse osmosis water systems come with:

  • Permeate pumps — Because it’s non-electric, a permeate pump improves filter efficiency because it can provide a means for less wasted water. A permeate pump also helps maximize the water pressure coming out of your home’s faucet.
  • Remineralization — Filtering water of contaminants can mean that you lose some beneficial minerals from the water. A system with a water remineralization filter adds minerals back to the water, creating better-tasting water and increasing health benefits.
  • UV light — To kill all the bacteria and microorganisms in the water, it is necessary to go beyond filtration and use UV light systems.

Other Important Reverse Osmosis System Terminology

You may come across unfamiliar terminology when comparing the best reverse osmosis systems. Being clear about what each term means can help you determine which filter to use, select the ideal models for your home, and make the right buying decision.

  • Filter Stages — Each reverse osmosis water model is a multiple-stage system. The system reverse osmosis process starts with pre-filtering, which removes large particles from the water. The next is a reverse osmosis filter that removes small particles from the water. Lastly, water filtration systems include post-filters, which reduce odors and adverse tastes for the water. Some RO systems also have an additional stage after post-filters to remineralize the water.
  • Storage tank — Almost all the reverse osmosis filtration water systems on the list have a storage tank. The main reason is that reverse osmosis filtration systems are not super fast. A storage tank can hold filtered water until it is needed.
  • Water per day output (GPD) — The amount of water the system can process per day is the system output. You’ll see systems measuring this as gallons of water per day (GPD). You might see references to gallons per minute, but the standard measurement is GPD.
  • Wasted water — Each of these systems wastes a certain number of gallons daily (GPD) as it passes through the RO membrane. As reverse osmosis water filters need additional water to flush the RO membrane, the system wastes a certain amount of water for every gallon of pure water produced.
  • pH — The pH of water refers to how acidic or alkaline it is when flowing through these systems. A high pH is alkaline, and a low is slightly acidic. Water with a high pH has an improved taste, whereas a low pH is corrosive.
  • TDS — Standing for total dissolved solids, these are contaminants the RO system removes. In doing so, these systems produce purified water.
  • Air gap faucet — An RO system features a drain line and a cross-connected cold water line. Preventing water in the drain from making contact with the clean water involves cross-connections that use an air gap faucet.

Installation and Maintenance of a Reverse Osmosis System

All RO systems feature a relatively simple installation process. A countertop system is the most straightforward system of all, as they sit next to the faucet and don’t require installation. However, an undersink system means that you have to drill a hole into the countertop for the faucet during installation. Under the sink systems typically come with a dedicated faucet or a separate attachment so you can use your existing faucet.

That means you may need the assistance of a plumber or handyman to complete the installation process so that you can use the faucet. If you prefer not to drill a hole in your countertop during installation, then under these sink water reverse osmosis systems are not the optimal choice.

Rarely is any maintenance necessary after installation beyond the replacement of filters. Typically, a pre- and post filter requires changing every 6 or 12 months and reverse osmosis filters every one to five years after installation. The manual for your filtration system specifies installation instructions and how often you need to change the system filtration. You can utilize a TDS meter to check the filters you use, too.

Before you purchase an RO system, make sure you run a water test. That water test helps you determine the level of filtration your water requires and show you what types of contaminants are currently in your water supply. Suppose you find high levels of the contaminants named above in your water. In that case, the installation of an RO system is ideal. However, suppose the problem lies with chlorine, an adverse taste, or odors. In that case, it’s wise to consider a standard water filter for your home’s water.

RO System Frequently Asked Questions

Will RO filters remove minerals from my water?

Yes. These water treatment systems typically remove calcium, fluoride, iron, lead, manganese, and salt. The process eliminates minerals because their molecules are significantly larger than what’s in water.

What’s the deal with chlorine and fluoride? Are they bad?

Municipal water supplies contain added chlorine to help kill off microorganisms and waterborne pathogens. Municipalities also add fluoride to help prevent tooth decay. The downsides of adding these chemicals into the water could cause health issues if the levels are higher than the recommendation. For example, too much chlorine could cause heart problems, and too much fluoride could cause elevated blood pressure.

Do RO filters require electricity?

No, these units run using water pressure. The only time electricity is necessary is if the model uses an electric pump or UV light.

Is it bad to drink reverse osmosis water?

The water that these machines produce without remineralization has low pH levels. If you drink water with low pH for an extended timeframe, there’s a chance it could cause gastrointestinal issues or kidney disorders but as long as you are getting healthy minerals from other sources this is not likely.

What is not removed by reverse osmosis?

Despite removing high levels of chemical impurities and other pollutants, these units don’t remove everything. For example, some pesticides, solvents, and volatile organic chemicals could still be present.

Is reverse osmosis the same as distilled water?

No, there are differences between reverse osmosis and distilled water. For example, reverse osmosis involves removing volatile chemicals and filtering water. Distilled water involves boiling water, capturing its condensation, and condensing it back into the water’s supply.

Is reverse osmosis better than regular filtered water?

Traditional filters do well at filtering impurities from water, but they don’t have the reverse osmosis membrane. In both of these filtering machines, you’ll find a carbon cartridge to remove chlorine and sediment. It’s the membrane in the reverse osmosis machine that removes almost all of the other pollutants.

Do I need reverse osmosis if I have a whole house filter?

This depends on your water quality. Remember, reverse osmosis filters are usually point of use drinking water filters while whole house filters are attached at the incoming water inlet to filter your basic water supply. If you have contaminants in your water that a whole house system cannot remove then it may be smart to install both.

Final Recommendations

After reviewing all of the best reverse osmosis systems above, we recommend a couple of standout filter options.

Suppose you are looking for the best technology and highest filter GPD output. In that case, we recommend the Waterdrop G3 System as the top choice for your home’s water.

Suppose you are looking for the best reverse osmosis systems with a storage tank and excellent water filtration capacity. In that case, we recommend the Aquasana OPTIMH20 system for your home’s water.

Each system includes water remineralization and is certified by NSF/ANSI standards to remove at the highest water contaminant level.

Suppose that you have contaminants in your water or your water just isn’t pure. Purchasing and installing one of these top-quality reverse osmosis systems can make your health, cooking, and drinking water ultra-safe. So, we advise you to invest in and use a high-quality RO system instead of a sub-par water system.

If you have questions about the ROes featured in this buying guide, please contact us for more information or use the comment section.

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