Are you ready to turn your tap into a fountain of purity? Welcome to the ultimate adventure in water filtration – the realm of Reverse Osmosis (RO) systems! As someone who’s not just installed dozens of these systems but also relishes the importance of drinking and using clean water.

Think of RO systems as your personal water wizard, magically banishing impurities and leaving behind nothing but pure, refreshing H2O. In this guide, I’m not just reviewing RO systems; we’re embarking on a quest to find the holy grail of hydration for your home.
So, strap in and get ready to explore the best RO systems out there. Whether you’re a family looking for the safest drinking water or a culinary enthusiast craving the purest ingredient, I’ve got the insider scoop to help you make the perfect choice. Let’s make a splash and discover the RO system that will transform your water experience at home!
Best Reverse Osmosis Water Filter Reviews
1. Waterdrop G3P600 RO Reverse Osmosis Drinking Water System – (Best Countertop RO)

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I think Waterdrop has a winner on their hands with the G3P600 they also have a G3P800 model, which can handle up to 800 gallons per day. It is an extremely user-friendly water filtration system thanks to its easy filter removal and color-coded filter labeling system.
Each filter has a dedicated job to do when it comes to filtering the water, and the filter labels identify what that is, and they each have a unique color. With five different filters, it would be easy to confuse them with one another; if that were to happen, you would not have the best filtering performance.
In addition to user-friendly attributes, the brushed nickel faucet looks modern and luxurious. The RO system has a few safety filters built-in to avoid leaks, and the included RO tank stand ensures that the tank will stay upright, avoiding massive issues.
The tank is sleek and does not take up much space under your sink. The 600 gallons of water it produces a day is massive as well. The average adult only needs around 1 gallon/day to stay fresh.
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2. Home Master TMAFC-ERP Reverse Osmosis System – (Best Under Sink)

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Reverse Osmosis (RO) water filtration systems are among the most popular choices for homeowners. The Home Master TMAFC is one of the highest-rated filters in the class. The system’s overall design will work for any kitchen; it is small and compact for a RO system while still providing all the key benefits one should expect from a RO system.
The 7-Stage filtration system greatly filters out all the common water contaminants you will find in municipal water supplies. By combining the features of Reverse Osmosis with 7 specific stages of filtering, you will notice an immediate improvement in the water’s taste, clarity, and odor.
The easy installation of the RO System is one of its most popular characteristics. Many folks get nervous about installing anything in their home, but plumbing can be something that people avoid at all costs. With the Home Master system, you should have no fear! It was designed with the consumer in mind, and we are confident that this is one of the easiest DIY water filter installations that you can find.
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3. APEC Water Systems 6-Stage Reverse Osmosis System

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I cannot say enough good things about the APEC Alkaline system. The installation is smooth, and the added instructions were detailed and very easy to follow.
The six filtration stages do an excellent job of removing various contaminants and even tackle total dissolved solids! The additional pH level from the alkaline filter was measurable in water testing and made the water taste great!
The reverse osmosis tank is small enough to fit under most sinks and quietly refreshes itself. The alkaline filter that was supposed to add minerals to the water did just that as our calcium levels grew after water testing.
There is a reason why the APEC system is so highly rated all over the world; it is a quality product and is easy to maintain.
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4. iSpring RCC7AK 6-Stage Under Sink Reverse Water Filter System

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iSpring has a long list of reverse osmosis systems for us, and the RCC7AK 6-Stage filter proved a great choice for many homes. The six unique stages of filtering re-mineralization greatly remove impurities and total dissolved solids from your water.
We especially liked that the filters are long-lasting and very easy to change in and out. Installation is made easy because the iSpring system includes multiple thread fittings so that your existing water line can easily be attached to the RO system.
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5. PureDrop Under Sink 5 Stage Reverse Osmosis Filtration

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Installing the PureDrop RO system was a joy. They took the time and detail to ensure that each word in the instruction manual made sense, and it would have been hard to screw up this install.
The quick-connect fittings are a game-changer, in my opinion. They are easy to connect, and they are going to protect against any leaks that may occur.
All the materials are made up of food-grade parts, and I feel like this will help combat bacteria build-up over time in the water lines. The five filtering stages effectively remove impurities, and the water tastes great.
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6. iSpring RCC7AK-UV 75GPDUnder-Sink Reverse Osmosis

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The iSpring system is back on our list, but this time it improved the final stage of water purifying. While water is in the holding tank, an ultra-bright UV light is shining down on your water, killing any sneaky little toxins that could have made their way through the filtering. This results in some of the best-tasting water we have tested.
The European-Style brushed nickel faucet looks great and is highly functional. Too often, manufacturers will include a cheaply made faucet, which ruins the experience for many people. You will not have that issue with this iSpring product or any other. You should not be concerned about installing this system; it was straightforward.
This economical water filter and softener system is America’s favorite brand of water filtration system. It is based on a 5-stage reverse osmosis system and mounted under the sink for easy storage and fitting.
It removes up to 99 % of contaminants, including lead, chloride, arsenic, asbestos etc. The system can easily be installed by yourself with all parts included and clear, easy to follow instructions and videos.
To fit, attach the tubing to quick-fitting connectors and lock. No threading pipes are needed. Water enters the system through a series of filters. The first is a PP sediment filter. Next is the Carbon KDF (GAC) filter, and finally, a carbon block (CTO) filter.
These remove large contaminants and protect the RO membrane from chlorine and other chemicals. Next, is the RO filter which removes particles down to 0.0001 microns, ensuring that your water is as pure as possible. Water then passes through a final GAC filter before arriving at the faucet. This gives you bottled quality water with no hardness and no sodium.
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7. Express Water Reverse Osmosis Water Filtration System

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When it comes to installing and inserting the filters into the Express Water System, it simply could not be easier thanks to Express’s easy-to-read and detailed filter labels. Each filter is clearly marked with an abbreviation that tells you the filter’s micron rating and a number that tells you which stage of the filtering process it goes.
The filters are easy to change out, too! An included water tank stand keeps the tank upright and safe from spills or other disasters.
In addition to simple-to-use filters, the Express system does a wonderful job of removing several contaminants found in many water supplies. In total, 108 major contaminants will be removed throughout the RO process and 5 stage filtration process.
The first 3 stages of the process do a great job removing sediment, chlorine, and other contaminants that cause odors and poor tastes. The 4ths stage is the one that does the heavy lifting; it grabs the fluoride, TDS, and other small micron elements.
The Express System can produce over 50 gallons of purified water in a day. Thanks to the dedicated faucet, this should easily accommodate the drinking water and cooking needs of everyone in your home.
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8. iSpring RCS5T 500GPD Commercial Tankless Reverse Osmosis

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For over ten years, iSpring has been a staple within the filtration community, and products like this are the reason why.
Many RO systems need holding tanks and take up a lot of space. But the iSpring RCS5T uses a pump and water discharge system, which saves space and still provides all the benefits of a RO system.
The 5-Stage filtering system has unique levels that each target a different type of contaminant. Starting with the sediment removing layer and ending with a carbon filter, your water will come out clean, odorless, and pure.
The included chrome faucet is one of the nicest optional faucets we have seen and is a great addition to your sink and countertops.
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9. Whirlpool WHER25 Reverse Osmosis (RO) Filtration System

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Whirlpool is one of the most trusted names in household appliances, and they have entered the reverse osmosis water filter game with an affordable, effective product.
The three stages of filtering are less than multiple competitors, but water testing proved that this system can still hang.
The filters are some of the easiest we have installed to this point. The twist-lock technology is simple, but it feels solid, and I do not believe that any leaks will be happening. The filters have a long lifespan and will not require changing very often. The LED indicator light gives you peace of mind, as well.
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10. Aquasana OptimH2O Reverse Osmosis Systems

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It will be a quality product when a reverse osmosis system has NSF/ANSI certifications. But when it has 5 (!), you can be confident you are getting a unique product that can filter water with the best of them. It is certified by NSF/ANSI for standard P473, the only RO system that has this certification.
Standard P473 means that the water is free from any additional acid that may be in the water. This gives me peace of mind that this RO system is accounting for every little thing that could be hiding in the water.
The multiple different faucet choices are great, too. I can pick and choose which one matches my kitchen the best, making it look great while providing me with quality drinking water.
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What is a Reverse Osmosis Filtering System?
Commonly referred to as a RO System, the reverse osmosis system is a unique but highly effective way to purify and filter water in your home. It uses a combination of standard water filters and usually a large tank that contains a filtering agent that removes water impurities.
The RO system is a wildly popular choice among homeowners because it combines some of the best possible filtering solutions on the market and is an additional step that will remove even more impurities from the water supply.
How Does a Reverse Osmosis System Work?
What makes reverse osmosis systems so effective is the exhaustive filtering process that the water must go through for it to make it to your glass. Water will be forced through a series of standard water filters before it heads into the membrane section where water is further purified. The specific number of filters will vary by which model RO system you have.
The membrane section will contain resin or some agent that can help toxins and contaminants within the water be captured. This allows for the cleanest water possible to be let through and into the clean water reservoir.
As water goes through the membrane section or resin, the water will be split into two separate water streams. One is the stream of purified water and is called the permeate. This is the final product of the water and will be what comes from your faucets or out of your RO system’s dedicated faucet that you added to your countertop.
The other stream of water will not make it through to you; it is called the concentrate. It will be discharged and drained from the system after the process is over. The concentrate stream is made up of water containing all the toxins and impurities the membrane removed from the water supply.
Each RO system will have a different resin or filtering membrane, but one that is shared across all models is the need to drain the wastewater that will not be reaching your faucets. This will occur periodically throughout the day and usually takes between 5 and 15 minutes.
RO systems have a maximum amount of water they can handle daily. Once that limit is reached, water quality will be lowered. To get the system back to working at its highest capacity, the reverse osmosis system will refresh itself, and this will cause the resin and the filtering membrane to be able to remove contaminants once again.
Reverse Osmosis Water Benefits and Risks
An enormous benefit can be achieved by installing a reverse osmosis water purification system in your home. A few risks are involved, but we will discuss how many manufacturers are addressing these risks for us.
Benefits
First and foremost, a reverse osmosis water system is one of the best all-around water solutions any homeowner can buy. RO systems can remove the most difficult commonly found water contaminants. One of the biggest headaches that homeowners face is how they can remove total dissolved solids from their water supply. Total dissolved solids (TDS) are made up of chemicals that have been dissolved within a water supply.
These things can be made of organic matter that comes from the environment or inorganic matter like calcium, sodium, and sulfates. These things are especially tricky for non-RO systems to remove. They are virtually invisible because they have dissolved into the water and can be filtered in the traditional sense.
Another major benefit of the reverse osmosis process is the wonders it can do to protect your piping and household appliances. I am sure you have heard of “hard water”. Chemicals that make water hard, like calcium and magnesium, can cause limescale and mineral scale build-up into your pipes and appliances.
Faucets and showerheads are especially vulnerable to scale build-up and can cause issues with an overload of scale build-up. The membrane process that reverse osmosis possesses is the only solution to keep water “soft” and free of these toxins. Because the membrane is semi-permeable, reverse osmosis will remove these contaminants but still let clean water through the membrane.
In addition to the TDS removal and scale combatting qualities of a reverse osmosis system, RO can also remove thousands of other contaminants. Most notably, heavy metals like lead can be removed using reverse osmosis, bacteria, and cysts.
Risks
You need to address a few things that a reverse osmosis system cannot handle on its own. The most important thing is chlorine removal. The layer of the reverse osmosis membrane that removes total dissolved solids can be damaged by chlorine. Years ago, this was a concern for many homeowners because chlorine was a leading cause of tastes and odors associated with hard water. Fear not, though!
Many reverse osmosis systems are now combining the RO process with a series of filters that can specialize in removing even more contaminants. You need to remove chlorine before reaching the reverse osmosis portion of the system. Carbon filters best do this, and many reverse osmosis filters have these included on the market. Without a clean carbon filter, you will see a decrease in the water quality produced by the RO system.
Reverse Osmosis Bottled Water vs. RO Machine
People are always striving for their home water supply to be made up of “bottled water quality” water. All this means is that they have filtered water that has all the benefits of RO systems and a series of filters. It is true that bottled water is healthy and is very high-quality drinking water, but there are some things to be concerned with when it comes to comparing it to a RO system.
Firstly, bottled water is EXPENSIVE. The money you would save from installing a RO system and achieving the same water results is mind-blowing. Most filters can replace over 150 single-use plastic water bottles, and if you do the easy math, the RO system will be saving you money in just a few short months.
Another thing to consider is the amount of water you get from a RO system versus bottled water. RO systems can produce 75+ gallons of filtered water every single day. Bottled water is limited to a few ounces at best. With a RO machine, you have virtually unlimited water if you are using the standard amount of water most humans use daily.
Why Do I Need a Reverse Osmosis System?
We get this question a lot, and what it comes down to in the end is your specific water supply and its unique characteristics. Some homes have differing levels of TDS and chlorine, while others are fighting heavy metals like lead. It comes down to getting a water test and figuring out exactly what you are dealing with. I typically recommend RO systems to clients because they are one of the best options for getting the best water possible.
How Do I Choose a Reverse Osmosis System?
Water Demand and Usage
One thing to remember with reverse osmosis systems is that they are limited to a specific amount of clean water they can produce daily. You must account for this when deciding the best reverse osmosis system for you.
They say that most people will use between 1.5-2 gallons of water per day for drinking and cooking. Most RO systems can handle over 75 gallons, so this is not a worry. But if you want a whole-home RO system for showers, cleaning, and daily use, you want to ensure that your purchasing system can handle this capacity for all family members.
Storage Tank
Because the RO process separates water into two streams, that water needs to be stored somewhere. Most systems will use a tank of some size to store water when not in use. You must carefully check that the tank size fits in your home.
Under-sink RO systems designed for use with your kitchen sink must fit under the sink and be hidden unless you want a big ugly tank on the floor. When it comes to whole-home RO systems, these tanks are usually bigger, and some systems even use several smaller tanks to accomplish what one large one can. I cannot stress how important it is for you to account for this; you would be surprised how many people fail to.
Alkaline Re-Mineralizer
Many homeowners love adding an alkaline re-mineralizer to the RO filtering system. An alkaline re-mineralizer will add valuable pH levels to your water and ensure that healthy minerals found in water will be retained and restored.
When the water has a pH above 7, it is referred to as ‘alkaline’, and research shows that this is great for the human body. Many RO systems offer this included, and it is a great option if you decide to go that route.
The right amount of calcium can be safely added with an alkaline pH cartridge, softening your water. While you may not precisely want ‘mineral water,’ this feature can also help neutralize slightly acidic water.
Water at neutral pH is always the best to drink.
Water Pressure
One thing you want to ensure is that you address is the water pressure that you will get from the reverse osmosis system. Flow rate is a hot-button topic regarding water filtering, and RO systems are no exception to this conversation. You must remember that the water is being put through multiple staging levels with 0.3 Micron filters that will stop almost anything in its path. Add that to the RO process, and you must assume that water pressure may be lessened.
You may be surprised that water pressure with RO systems is better than many other purification processes. The reverse osmosis system uses force to make the water move through the semi-permeable membrane, which forces the water to speed up through filtering.
Different RO systems will be able to account for water pressure differently. You will want to be on the lookout for the term flow rate; this will tell you a lot about the RO system’s water flow rate. This will be rated by gallons per minute or GPM, for short.
Semi-Permeable Membrane
At this point, we have discussed the semi-permeable membrane that reverse osmosis systems use during the filtering process. Each RO system will have unique materials that make up this membrane, and eventually, they must be replaced. This membrane material will often be made of a special resin that can absorb toxins and water impurities.
The resin will grow, and eventually, it will need to be replaced. Some newer models will use a membrane cartridge that acts like any other standard water filter. Keep an eye on it and ensure you replace them on time, and this semi-permeable membrane will work for years without needing maintenance.
The longevity of the membrane material will depend entirely on the RO system that you decide on, but there are a few things you want to investigate. Make sure you choose a RO membrane that will last long enough to make it worthwhile. Some will last longer than others, and if you constantly replace it, you will spend money on new materials often. Speaking of money, you want to see how much replacement membrane material is or how much a replacement membrane filter is; some can be very expensive.
Water Purity
The most important thing you can explore when deciding on the best reverse osmosis system is the water purification it can achieve. You will need to know exactly what each different system can remove from your water and ensure that you choose the one that aligns closest to your water supply.
I cannot stress the importance of completing an in-depth water test showing you every toxin and contaminant in your water supply. The effectiveness of each system will be different, and instead of just looking for the “Best RO System,” you should be looking for the right one.
Leak-Free Protection Fittings
I always get calls regarding leaks within someone’s RO or standard water filtration systems. This can easily be avoided by securely fastening the fitting between all filters and water lines. Many RO systems now come with leak-free fittings that will ensure that no water leaks out and into your home Water damage can cause thousands of dollars in damage and has been known to ruin homes. Take the time to investigate the fittings and ensure you choose a water filter that comes with quality, leak-free fittings.
Ease of Installation
Most reverse osmosis systems are designed to have the homeowner install them. This saves hundreds of installation costs. But the reality is, some systems are easier to install than others. Plumbing terrifies a lot of homeowners, and if you are in that group, you will want to ensure that the reverse osmosis system that you purchase can be easily installed. Install times will vary based on the number of features your system has and if you purchase a whole-home or under-sink system.
Under-sink systems have very little water line connections to deal with, and they are typically much simpler to install than a whole-home system. Keep that in mind, when deciding on the type of RO system you would like. I like to ensure that the RO system will come with detailed instructions and support. Many companies are now offering free online tutorials to help install the system, which is a great resource for many people.
Replacement Filters
There are two important things to remember when it comes to replacement filters: longevity and cost.
Filter life will vary from system to system, and I like to find a happy medium between filters that are longer lasting but still have the best filtering capability. Ensure that your filters will be long-lasting, this keeps your RO system as maintenance-free as possible.
Before buying any RO system, you will also want to know the replacement filters’ cost. Too often people buy a filtering system only to realize later that the cost of a replacement filter is way too expensive! Knowing this information beforehand is invaluable.
Electric Booster Pumps
With some of the more expensive models that can produce over a hundred gallons daily, there is usually a device to increase water pressure.
These amazing electric pumps help keep the system working at maximum capacity. If your water is not up to the necessary pressure, these boosters will work better than a mechanical ‘permeate pump.’
Our top choice comes with as many as four pumps, greatly enhancing whole-house reverse osmosis performance.
Drain Ratio
The first hesitation people have when buying an RO system is that they will be wasting too much water.
Most RO systems produce a large amount of wastewater (several gallons) just to give you a single clean gallon. However, the best whole-house reverse osmosis water filtration systems we showcase have just a 1:1 waste to pure water ratio.
This is due to the advanced RO membranes used (for example, the dual-flow membranes for the iSpring RCS5T model) and the pressure-increasing booster and permeate pumps.
Tanked Or Tankless
Tankless models work best for smaller households that don’t have the necessary space to install a large tank under the sink.
Tap water is filtered and immediately ready to be enjoyed. Larger corporate settings will benefit from a tanked system since such systems often have a higher capacity and can store some water quantity before consumption.
Filter Size
Almost every RO filtration system comes with 10” filters, the standard size. However, a few models come with larger filters (including the 20” filters for the iSpring RCB3P).
Such ‘oversized’ filters give a larger surface area for filtering the same amount of water, trapping twice as many contaminants. This also helps reduce the waste-to-pure water ratio, so many people are concerned about it.
How Do I Install a RO Purifier?
Thankfully, most RO systems are now designed to be installed by the homeowner. Install times will vary depending on the type of system you go with. Under-sink systems can usually be installed in an hour or two, and many systems now send links to instructional videos and detailed instructions to make it simple.
For under-sink systems, you will need to link the RO system’s water supply line to your existing cold-water line. You will want to prepare the area where the faucet will be mounted to the top of the sink or counter. Feed the water and the wastewater line through that opening and connect the water line to the faucet.
The wastewater line will then connect to your existing sink’s drain line; this will be how the excess water gets removed from the system. Mount the filters to the cabinet wall or floor, and you are done! Make sure to sanitize everything after you are done!
Whole-home systems can be more advanced when it comes to installation. They are bigger and more intimidating to many homeowners. But really, the idea remains the same as any other reverse osmosis system available.
The most significant difference is that you will be connecting the main water supply of your home to the RO system rather than a single faucet and sink combination. You will want to ensure that you have enough space in your utility room or area that you will be preparing and installing the RO system. Depending on where your main water supply enters the home, you may want to investigate the possibility of soundproofing your room. RO systems need to be reset and replenished, and this can be noisy.
Frequently Asked Questions
What substances do reverse osmosis systems remove?
RO systems are one of the few filtration types that can effectively remove total dissolved solids (TDS).
Does the RO system pose any risks to your health?
As long as you are maintaining your RO system, the health risks are minimal.
Do all reverse osmosis systems remove fluoride?
Yes! A properly manufactured reverse osmosis system will remove fluoride!
Do you reverse osmosis systems waste a lot of water?
This is the most hotly debated thing surrounding reverse osmosis water systems. Because the semi-permeable membrane will capture contaminated water molecules that require draining, there is water wasted. However, many systems can produce less wastewater than others.
How long does a reverse osmosis system last?
RO systems are notorious for lasting many years. If you maintain it properly, you will enjoy years of purified water.
Can I install a reverse osmosis system myself?
Of course! Many manufacturers are supplying DIY videos, 24/7 support, and detailed instructions for homeowners to be able to install RO systems in just a few hours.
Conclusion
Reverse osmosis water filtration is one of the most popular choices among homeowners from all over the world. Each home is unique, and the water supply is no different. Reverse osmosis systems can improve water that comes from any environment. With the evolution of RO systems and water filters, you now have more options than ever to provide your family with quality, healthy drinking water.
We understand that choosing the best reverse osmosis system can be intimidating. We are confident that our step-by-step guide will point you in the right direction. There is something available for every budget, space, and style, and we are confident that the best reverse osmosis system for your home is somewhere on these pages. We sincerely thank you for taking the time to read this article, and we wish you success in finding the perfect reverse osmosis water system.
One of the most significant benefits of having a reverse osmosis system is that you’ll have cleaner and safer water to drink. Unlike traditional filtration methods, reverse osmosis systems can remove even the smallest contaminants from your water supply, including lead, arsenic, chlorine, and fluoride.