The quality of reverse osmosis systems goes beyond low water wastage, filter life, and large tank size. Undoubtedly, the said features are valuable to the overall effectiveness of a reverse osmosis water filtration system. However, features like water output, number of filtration stages, and TDS reduction rate are more influential to the overall performance of a reverse osmosis system.

When compiling this list of some of the best reverse osmosis systems, our priorities were all-inclusive.

Best Reverse Osmosis System at a Glance

  1. Best OverallWaterdrop G3 Reverse Osmosis System
  2. Best Under SinkSpringwell Reverse Osmosis Drinking System
  3. Best CountertopAquaTru Countertop Water Filtration Purification System
  4. Best Tankless SystemWaterdrop Tankless Reverse Osmosis System
  5. Best Whole HouseUS Water Systems Defender Whole House RO System
  6. Best BudgetExpress Water RO5DX Reverse Osmosis Filtration
  7. Best for ApartmentAlcaPure Reverse Osmosis Countertop Water Filter
  8. Best for Well WateriSpring RCC7AK-UV 7-Stage Under Sink Reverse Osmosis
  9. Best Reverse Osmosis Ice MakerAPEC Water Systems Icemaker Kit

There are two main types of reverse osmosis systems: 1. Cellulose Triacetate Membrane and 2. Thin-Film Composite Membrane. Of both options, the thin-film composite membrane (TCM) offers a better filtration process against standard harmful contaminants. However, it cannot stand chlorine. Hence, it is only used for filtering chlorine-free water.

Unlike TCM, Cellulose Triacetate Membrane (CTA) is more tolerant to chlorine. So, it works on water containing chlorine. However, its reverse osmosis filtration process is not as effective as TCM against standard harmful contaminants. Also, CTA is more susceptible than TCM to bacterial contamination.

Our Best Reverse Osmosis System Review

1. Waterdrop G3 Reverse Osmosis System

Waterdrop G3 Reverse Osmosis System

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The Waterdrop G3 Reverse Osmosis System is the best for both small and big families that need highly purified water.

It combines a high water output with multiple filtration stages and a high TDS removal rate. None of the other reverse osmosis filter systems in this review have a better combination.

Filtration Stages and Filter Life

This product has a water output of 400 gallons per day – only the Defender Whole House RO System has a higher output. With this output, you can expect to always get quality drinking water, even when you have a full house.

The Waterdrop G3 is a 7-stage reverse osmosis system. Every water drop moves from a PP cotton to an activated carbon filter, bacterial inhibitor, PP cotton, reverse osmosis membrane, activated carbon filter, and PP cotton, in that order. These make this reverse osmosis water filtration system very thorough. Basically, the water goes through so many steps that it is hard to imagine any significant contamination remains at the end.

The 7 stages of the Waterdrop G3 features PP cotton filters in 3 stages. These filters are there to remove large-sized particles, including sediments and rust. Some assurance that you are 3 times less likely to see large-sized contaminants in your drinking water.

Then there’s the granular activated carbon filter in 2 stages, which helps the filtration process by removing contaminants that can affect water taste and smell. With this, you are 2 times less likely to get smelly water or water with an unpleasant taste.

Of course, this reverse osmosis water filter features a reverse osmosis membrane in its 7-stage filtration system. This does the total dissolved substances removal, and it has a nominal efficiency of around 91.9% – one of the highest you’ll find amongst reverse osmosis filters. The RO filter has a lifespan of 24 months or 2200 gallons. This is pretty much the highest many of the best reverse osmosis systems offer.

This RO system also features an inhibitor in its 7-stage filtration system. This helps preclude the likelihood of bacteria fouling the RO membrane. Remember, we mentioned how bacteria can ruin RO membranes.

Water Storage and Wastage

The product has no storage tank. So, you cannot always get water from it on-demand. However, without a tank, you will have no problem finding space for the installation process.

Overall, we believe the Waterdrop G3 is top-quality. Hence, its position in our reverse osmosis system reviews. But then, its water waste ratio is not the best on offer. About 50% of the water you put in this RO filtration system goes to waste. Apart from that, this product has no option for remineralization. So, if retaining some minerals is vital to you, this may not be your ideal option.

Pros and Cons

Pros
  • Multiple filtration stages featuring a sediment filter in 3 stages.
  • High TDS removal rate.
  • High water output.
  • Long RO filter life.
Cons
  • Water waste ratio could be better.

2. Springwell Reverse Osmosis Drinking System

Springwell Reverse Osmosis Drinking System

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The Springwell Reverse Osmosis Drinking System is the best for small kitchen owners that want to conserve water while getting their purified water.

Its compact design, low water wastage, and high TDS removal rate make it the perfect kitchen sink reverse osmosis system.

Filtration Stages and Filter Life

Unlike the two Waterdrop models in this review, the Springwell Reverse Osmosis Drinking System has 4 filtration stages. While this is decent, its reverse osmosis process will not be as thorough as the Waterdrops. But overall, it still works wonders.

This reverse osmosis filtration system uses a sediment filter in its first stage. In its second stage and fourth stage, it uses a carbon block filter to remove contaminants like chlorine and pesticides, which affect the taste, safety, and smell.

The reverse osmosis membrane filter of this system comes in at stage 3. It offers a nominal TDS removal rate of around 96.3% – one of the highest in the industry. The RO membrane of this RO system is typically intact for up to 24 months – also higher than many other reverse osmosis systems.

The system has a water output of 75 GPD. This is pretty much average compared to the other products in our best reverse osmosis system review. But as long as your water needs do not go sky-high, this should serve you well.

Water Storage and Wastage

The Springwell Reverse Osmosis Drinking System is not tankless. It comes with a storage tank that can hold 3.2 gallons of water (12 liters). This is pretty average, but it is fair for an under-sink reverse osmosis system.

This product excels when it comes to water conversation. It wastes only about a quarter (25%) of the water it gets for reverse osmosis water filtration. This is significantly higher than what many other reverse osmosis water filters offer.

If you prefer RO systems that recover vital minerals, you may not fancy this product since it has no option for remineralization.

Pros and Cons

Pros
  • Relatively better at conserving water.
  • Compact design suitable for under-sink installation.
  • Uses a 4-stage process for thoroughness.
  • Long RO filter life.
  • Comes with a storage tank.
Cons
  • Has no option for remineralization.

3. AquaTru Countertop Water Filtration Purification System

AquaTru Countertop Water Filtration Purification System

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This RO system is the best for small families that want an on-demand source of drinking water.

It comes ready-to-use and has a sleek minimalistic design that will fit into various places just fine. This is why we chose it as the best reverse osmosis system for countertop.

Beyond being ideal for countertops, the AquaTru reverse osmosis system has a high TDS removal rate and low water wastage.

Filtration Stages and Filter Life

The AquaTru reverse osmosis system is a 4-stage reverse osmosis system. While this is not the best in this review, it contributes immensely to this reverse osmosis system’s performance.

The reverse osmosis membrane of this RO system has a rated TDS removal rate of over 90% – typical of the best reverse osmosis systems. But while the manufacturer says it can last up to 24 months, it only lasted around 12 months for many people. This does not take anything away from its performance; you may just be replacing the Ro filter earlier than expected.

This reverse osmosis water system produces purified water at a rate of 1 gallon every 15 minutes. So, in a day, the maximum output is about 96 GPD – not bad for a countertop reverse osmosis filter.

Water Storage and Wastage

Of course, this product comes with a storage tank, but the tank has a 1-liter capacity – about 0.3 gallons. While small, the capacity of this product’s storage tank is not bad for a countertop reverse osmosis water filtration system.

Like the Springwell RO system, the AquaTru RO system only wastes around 25% of the input water. This makes it one of the best reverse osmosis filtration systems when it comes to water conservation.

If you want a product that recovers minerals after the reverse osmosis process, you should consider this product. While it does not come with a remineralization filter by default, the manufacturer offers the option.

Pros and Cons

Pros
  • Ideal for countertops and similar spaces.
  • Thorough 4-stage filtration.
  • Does not require installation.
  • Offers the option for remineralization.
  • Decent water output.
Cons
  • The storage capacity could be better.
  • Filter life could be better.

4. Waterdrop Tankless Reverse Osmosis System

Waterdrop Tankless Reverse Osmosis System

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This product is the best for families (big or small) that consume a lot of water.

It is the second of the two tankless reverse osmosis systems in this review. The other one is the Waterdrop G3, our best overall reverse osmosis water filter.

The Waterdrop Tankless Reverse Osmosis System offers a combination of high water output, multiple filtration stages, and a high TDS removal rate – just like the Waterdrop G3. So, choosing it as our best tankless system was easy.

Filtration Stages and Filter Life

Like the G3, the Waterdrop Tankless Reverse Osmosis System runs on a 7-stage filtration process. Of the 7 stages, 3 feature PP cotton filters for removing sediments and other large particles.

Granular activated carbon filter features in 2 stages of the 7-stage process for removing substances like chlorine, which affect odor and taste. In one of the 7 stages, there is a bacteria inhibitor to suppress bacterial activity and preserve the RO membrane’s quality.

Of course, the RO membrane is one of the 7 stages. It has a TDS removal rate of over 90% – not as much as the G3 but still an industry-high.

Unlike the G3, the RO membrane of this product has an estimated lifespan of around 12 months or 1100 gallons. Basically, if you opt for this over the G3, you may have to replace the filter more frequently.

The water output of this system – 400 GPD – is on par with the G3. It is also higher than many other osmosis systems offer. So, you can always expect good performance on the purified water production front.

Water Storage and Wastage

As the name says, the Waterdrop Tankless is tankless. So, installation space should not be an issue. Then again, you may not get water from it on demand.

Its water conservation is average; it wastes about 50% of the water it gets. It also does not have the option for remineralization.

Pros and Cons

Pros
  • It offers high water output.
  • Purifies water using a 7-stage filtration process.
  • The TDS removal rate is impressive.
Cons
  • Does not offer the option for remineralization.
  • Water wastage ratio could be better.

5. US Water Systems Defender Whole House RO System

US Water Systems Defender Whole House RO System

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The Defender Whole House RO System is the best for households that need purified water in every part of their house.

We chose this product as our best reverse osmosis water filter for the whole house because of its massive water output. But besides having an output high enough to serve a building, this filtration system has low water wastage, a high TDS removal rate, and a large storage capacity. But it falls a bit short when it comes to filter lifespan.

Filtration Stages and Filter Life

This reverse osmosis water filtration system produces purified water by passing your water through 6 stages. The first stage involves the removal of sediments and large particles with a 5-micron pre-filter. Then in the second stage, the RO filtration happens.

The reverse osmosis filter of the Defender Whole House RO System has a nominal TDS removal rate of around 98.5% – the highest we have seen so far.

The RO membrane also has a rated lifespan of 12 months. We’ve seen better from the other RO systems in the review, but this lifespan does not take much away from the overall quality of the product.

As we hinted before, the Defender Whole House RO System has a massive output of 2000 GPD – the others do not come close. It also comes in 4000 GPD, 6000 GPD, and 8000 GPD. So, even if your house is extra large, you can find something that works.

Water Storage and Wastage

Besides having a massive output, the storage tank that comes with this product is head above many other reverse osmosis filters. You can get the tank in two sizes: 140 gallons or 250 gallons.

Water conservation with this model is also very impressive. It only wastes around 20% of the input water – better than any of the other RO systems.

With the Defender Whole House RO System, there’s an option for remineralization. So, you can recoup some healthy minerals if you want.

Pros and Cons

Pros
  • Impressive water output – large enough for whole house.
  • Massive storage capacity.
  • High TDS removal rate.
  • Multi-stage filtration.
  • Low water wastage.
  • Offers the option for remineralization.
Cons
  • The filter lifespan could be longer.

6. Express Water RO5DX Reverse Osmosis Filtration

Express Water RO5DX Reverse Osmosis Filtration

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This RO system is the best for people that are not looking to spend too much but want to improve the quality of their tap water.

The Express Water RO5DX may not have the highest water output or tank size, but its TDS removal rate is pretty impressive.

Filtration Stages and Filter Life

The Express Water RO5DX filters water in 5 stages – the third-highest in our review. The first of the 5 stages involves sediment filtration. The second, third, and fifth involve adsorption with carbon filters. Then the fourth stage is where the RO happens.

The RO membrane of this product has a TDS removal rate of over 99% – the highest of any of the reverse osmosis systems in our review. But while its removal rate is impressive, its RO membrane lifespan of 12 months could be better.

This product has a water output of 50 GPD – the lowest of the RO systems in the review. But when you consider the price, this water output is fair.

Water Storage and Wastage

This water filter comes with a storage tank that can hold up to 4 gallons of water. This storage capacity is impressive. Some more expensive brands cannot store as much water.

The Express Water RO5DX does not impress on the water wastage front. It wastes around 60 to 80% of water supply into it. This is the lowest of all the RO systems we reviewed.

The Express Water RO5DX has no option for a remineralization filter.

Pros and Cons

Pros
  • It is relatively inexpensive.
  • The storage capacity is impressive.
  • The TDS removal rate is very impressive.
Cons
  • The RO membrane lifespan could be longer.
  • It water wastage ratio is pretty high.

7. AlcaPure Reverse Osmosis Countertop Water Filter

AlcaPure Reverse Osmosis Countertop Water Filter

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Thanks to its portable, modern countertop design, this AlcaPure Water Filter is the best for people who live in apartments and want a small unit for tap water purification.

Besides its portability and sleek design, the high TDS removal rate and long membrane life are features to look forward to in this product.

Filtration Stages and Filter Life

The AlcaPure Water Filter produces filtered drinking water through a 4-stage process like most RO systems.

The first stage involves sediment filtration using a 5-micron pre-filter. The second stage uses a carbon filter to remove chemicals. The third stage is the actual RO purification process, while the fourth is remineralization.

The RO filtration medium of the AlcaPure Water Filter has a 99% TDS removal rate – the joint second-highest in our review. It also has a filter life of 24 months, which is impressive.

With this product, you get a water output of 75 gallons per day (GPD). This is not the best you can get in the market. But since it’s just for your apartment, it should work fine.

Water Storage and Wastage

The storage tank of this RO system has a capacity of 0.5 gallons – only the AquaTru RO system has a lower capacity.

The AlcaPure Water Filter has a 1:1 drain line ratio. This means about half of the water supply it gets goes to waste. While this water wastage ratio is better than most water filtration systems, there are better options for water conservation in this review.

This product comes with an alkaline remineralization filter. So, you can recover healthy minerals such as magnesium and calcium.

Pros and Cons

Pros
  • Long membrane life.
  • High TDS removal rate.
  • Stylish design.
  • Multi-stage filtration for thoroughness.
Cons
  • Low water storage capacity.
  • Water wastage ratio could be better.

8. iSpring RCC7AK-UV 7-Stage Under Sink Reverse Osmosis

iSpring RCC7AK-UV 7-Stage Under Sink Reverse Osmosis

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The iSpring RCC7AK-UV is the best for those that want to purify well water. Alongside its multi-stage filtration, it comes with UV light, and these make it pretty effective for purifying all kinds of water.

Besides having a broad range, this RO system offers a high TDS removal rate and impressive filter life.

Filtration Stages and Filter Life

With the iSpring RCC7AK-UV, you are getting 7 stages of filtration – the joint-highest in our review. Of the 7 filtration stages, 3 stages involve sediment filtration using PP sediment filter and 1 involves chemical removal using carbon filters. Then at stage 5, there is reverse osmosis. Stage 6 features a finer granular activated carbon filter, while stage 7 involves remineralization.

Beyond the filtration steps, this product still uses UV light to inactivate or kill microbes in the water. So, in the end, the drinking water you get is almost as good as bottled water.

The membrane has a TDS removal rate of 99% – the joint second-highest. It also has a lifespan of up to 24 months. So, it is quality for sure.

The iSpring RCC7AK-UV has a water output of 75 GPD – not the best we have seen but not too bad.

Water Storage and Wastage

With this brand, you are getting a 3.2-gallon storage tank – about the same capacity as average RO systems.

When it comes to water conservation, this RO system does not impress. It wastes around 66% of the water it receives.

If you want to retrieve beneficial minerals, the iSpring RCC7AK-UV is an option for you. Like the AlcaPure, it comes with an alkaline remineralization filter.

Pros and Cons

Pros
  • Impressive TDS removal rate.
  • Long membrane life.
  • Filtration happens in 7 stages, so the output drinking water is of high quality.
Cons
  • The water wastage ratio could be much better.

9. APEC Water Systems Icemaker Kit

PEC Water Systems Icemaker Kit

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The APEC Water Systems Icemaker Kit is the best for people that need the means to generate ice with water coming directly from their RO system.

The APEC connects 1/4″ RO systems directly to ice makers. This way, the ice cubes you get will have a high level of purity. This ice maker also features a shut-off valve. So, regulating water pressure from the RO water filtration system to your refrigerator is much easier.

The reverse osmosis ice maker kit is 20 feet long. So, whether your RO system is close to the refrigerator or not, you might still be able to connect them without fuss.

The only problem you might have with this product is compatibility. If your RO system uses wider tubing, this will not work.

Pros and Cons

Pros
  • Features a 20-feet tubing for seamless connection over distances.
  • Comes with a shut-off valve for better water pressure regulation.
  • Easy installation.
Cons
  • Will not work with 3/8″ RO systems.

Buyer’s Guide for Reverse Osmosis Systems

Water Waste

One unavoidable downside of RO filtration is water wastage. Reverse osmosis systems remove contaminants by passing water molecules through a semi-permeable membrane. But in doing so, some of the water supplied to the system must remain with contaminants. Of course, this water becomes waste because it is contaminated, and you cannot drink it.

When buying a reverse osmosis system, pay attention to how much water goes to waste after filtration. The value is typically indicated as a ratio or as a percentage. Of course, your goal should be to buy a system that has the lowest water wastage.

Water Output

The water output of a reverse osmosis system is an indication of how much water the system can produce per unit time. The higher the water output, the more drinking water you can get from your RO device.

When buying an RO system, you must consider how much water you and your family consume per day. This will help you choose the reverse osmosis system with the most suitable water output.

Tank Size

If you want to get water directly from your RO system on-demand, buy one that comes with a tank.

When choosing a reverse osmosis system that comes with a tank, pay attention to tank size. The larger the tank size, the more water the system can provide to you on-demand.

Remineralization

RO water filtration systems remove minerals like calcium and magnesium to improve water quality. But some people would rather have those minerals in their water.

If you prefer retaining beneficial minerals in your drinking water even after filtration, opt for a system that has a remineralization filter.

Filtration Stages

For thoroughness, many reverse osmosis systems feature multiple filtration stages. Each stage works on specific types of impurities in the water, ensuring that nothing gets past the filters. If this type of thoroughness appeals to you, you should look out for a product with a high number of filtration stages. Having more filtration stages might just bring the water quality close to bottled water.

Talking about thoroughness, you could keep an eye out for a system that features UV light too. Having UV light in the system minimizes the chances of microbial contamination.

Pros and Cons of Using a Reverse Osmosis Water Filtration System

Pros
  • Removes a large percentage of contaminants.
  • Improves water odor and taste.
  • Provides high-quality purified water.
  • Purified water from RO is suitable for cooking and even washing.
  • The system is safe.
  • Requires minimal maintenance.
Cons
  • High water wastage.
  • Removes healthy minerals.
  • May cause a drop in water pressure.
  • Disposing of waste water is not straightforward.

Frequently Asked Questions (FAQ)

How does a reverse osmosis system work?

Reverse osmosis systems remove water contaminants by forcing contaminated water through a semi-permeable membrane. The said membrane will allow water flow through it while holding the contaminants back. With the contaminants separated from the water, you get pure water.

Is it worth getting a reverse osmosis system?

Getting a reverse osmosis system is worth it. Not only do reverse osmosis systems improve water quality, but they also help prevent various types of diseases.

Is drinking reverse osmosis water bad for you?

Reverse osmosis water is safe to drink. However, if you have a disease or condition that causes mineral deficiency, you should not drink reverse osmosis water. Reverse osmosis water typically contains less minerals than tap water. So, if you drink it, it will not help your mineral deficiency. In fact, it may even worsen the deficiency.

Conclusion

When buying a reverse osmosis system, it is okay to set your sights on filter life, water waste ratio, and storage tank capacity. But if you want true quality, ensure you prioritize TDS removal rate, multiple filtration stages, and high water water output.

About the Author

Paul Morton

Founder and Editor

Paul is a retired plumber who now spends hours on home improvement projects. From fixing toilets to leaking pipes in crawls spaces, there is nothing Paul can't do or wouldn't try. Paul was running his own plumbing company and is our expert in regard to all types of water filtration systems.

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