Reverse osmosis – what is that? Put most simply, this is a process which purifies your water – typically used for house water, but can also be used on an industrial scale. Pretty easy to understand, but harder for the layman to know which of these are the best reverse osmosis systems available. For instance, how does it work and why would you need it? Well, if you live in a large city or newly developed area, you’ll especially want to consider this approach to cleaning your water.
For this review, we’ve chosen ten of the top models available, based on their number of filtration stages, the gallons which can cycle through them per day, the size and ease of installment, and the overall reduction of contaminants. Additionally, this research provides advice to distinguish between the best reverse osmosis system for you, and the rest on the market.
Our research comprises direct questions to the manufacturers, opinions from reviewers about what they liked and what they didn’t, as well as an analysis of product specs and test results. To make it more accessible and easier to understand, the products are organized in tables highlighting their features, detailed descriptions, and pros or cons. This table is followed by a buying guide to help you best make your purchase; it’s our goal to make it very easy for you to pick the best reverse osmosis system on the market.
More features: additional Alkaline Remineralization (AK) stage
This is by far the best example of a point of use filter available on the market. It mounts below the sink with moderate assembly, and then works to remove up to 99% of all water contaminants (that’s over 1000 particles from your hard water). With lead specifically (higher amounts leading to lead poisoning) this high-end filtration system removes up to 98% every time. Additionally, this can be stalled at the point of entry to your refrigerator or even your shower, guaranteeing crystal clear ice cubes for your drink or softer water as you get clean. Best of all you don’t have to worry about the first five stages through the RO membrane removing helpful minerals because the sixth stage of purification – an alkaline remineralization filter – restores all these healthy minerals to your water.
Typical assembly can take up to an hour, but the instructions are professionally lined out and easy to follow; the manufacturers also are on call for any questions or advice. This will fit under any standard kitchen sink, and it’s guaranteed to make your water taste better, feel softer, and be healthier.
More features: adds calcium and magnesium minerals twice during the purification process
This can be used as both a POU system or a POE system, meaning that the tank is large enough and the membranes are strong enough to attach at the location where water enters your house and filters all water – for your kitchen sink, bathrooms, and refrigerator. It also comes with the largest number of purifying stages, the first 5 stages which remove all chemicals, bacteria, and hard water materials. Stages 6 and 7 use patented full contact technology to reintroduce good minerals for added taste and necessary health, including additions of calcium and magnesium minerals which you need in a regular diet. Additionally, a built-in non-electronic pump can be purchased which will reduce the systems water waste by 80%. The filters are long-lasting, easy-to-change, and require no wrenches or other tools.
More features: 7 replacement filters
This NSF and ANSI rated system is designed to efficiently filter your water in five stages, first getting rid of any fibers, dust, colours, and odors. In the final stages of purification, it removes up to 99% of all contaminates in your water, extracting all heavy metals, chemicals, and bacteria. Unlike six stage RO systems which reintroduce good minerals, this system does not, but it does come with a 1-year warranty and seven extra replacement filters. Replacement filters are normally quite expensive and the cost can slowly add up, but with seven extra you don’t need to buy filters for at least 2-3 years of use. Included in your purchase is a European-made 100% lead-free faucet, and the added instructions for the entire system should make installation quite easy. In no time at all you’ll be drinking healthier, crystal clear water. Whether you get your water from the city, a well, or the local reservoir, this filtration system will do a fine job keeping your water safe from pollutants.
More features: fast flow faucet with 0.8 GPM delivery
This system will filter your water until the tank is full, rather than working every time you turn the tap, and therefore you’ll have a full tank of crystal clear water every time you need it – refills automatically without having to be reset. It comes with 5 stages of purification and the filters are coconut carbon, giving your water a natural taste. In case of any leakage, the system comes with a detector that shuts down water purification if any unwanted moisture gets out. The reason this is our budget pick is that it not only removes hard components from all your water, but it also comes at the best price for such high quality.
More features: 100% lead-free designer faucet
Another great six stage filtration system. It not only removes up to 99% of negative solids from your water but it also adds in calcium minerals to improve the taste of your soft water. For those who love mineral water, this system reintroduces good minerals in its sixth stage as well as that calcium taste; bottle your water right at home and save money. During the first stage a high-capacity polypropylene filter removes rust, particles, and dust. The next three stages eliminate chemicals, odors, cloudiness, and other unhealthy solids. These solids can be anything from deadly arsenics and leads, to bacteria and viruses. Once its done with all its stages, including the sixth one which revitalizes with water, you won’t be disappointed by what comes out of the tap: pure, good tasting, healthy water every time.
More features: free from water leaks, bursts and noises
Providing water tasting far more superior to bottled water, not only is it healthier for you, but it also saves your money in the long run on bottled water throughout a year. This top tier brand is designed with 5 contaminate-removing stages that are NSF certified and will remove up to 99% of all hard pollutants. This system is ideal for cities where tap water is full of chlorine, heavy leads, too much fluoride, bacteria, and other viruses. As an added bonus, its filters are certified to last twice as long as other brands, meaning less money spent on replacing them and more extended use of your reverse osmosis system. Very comprehensive installation manual makes it easy to install so that you can do by yourself right at home. One moment – unhealthy city water, the next – you’re sipping fresh crystal-clear water.
More features: quick connect fittings caps for easy installation
This product from iSpring uses its first three filtration stages to do away with sediment, rust, pesticide, chlorine, you name it! This POU reverse osmosis system is made to fit in most under-sink cabinets, but can also be installed in a recess of the wall where water enters toward the kitchen, or bathroom if you want to use it for baths and showers. Equipped with a high capacity polypropylene sediment filter, this product filters all hard water down to 5 microns (that’s nearly 96% filtration). These first three stages of filtration also have strong enough membranes that they don’t need replacing till at least the end of their first year being used or longer. Perfect for a family of 4 (or more depending on your water usage), the filters have the capacity to clean 100,000 gallons of water for one full year of pure water.
More features: comes with nickel all-metal faucet and clear see-through 1st stage housing
This mountable system can fit quite snuggly in a utility room – connected to pipes for your shower or bath – or in your under-sink cabinet in the kitchen. With a five-stage purification system, this takes your unfiltered water and removes the lead, chlorine, arsenic, calcium, giardia, and other hard water pollutants. It has a 99% rate of removal (that’s over 1000 contaminants), so that you can experience clean, safe, and good-tasting water every time you turn on the faucet. A trustworthy brand, this system has been certified by the NSF, ANSI, and the WQA (Water Quality Association). Rated among the best under sink water filters, it will fit under a standard sink, is leak-free, and comes with a brushed nickel all-metal faucet.
More features: 100% lead-free designer faucet
Another POU connecting system, this was built with supreme quality and moreover, it comes with a 2-year warranty. The system includes all the parts for a five-stage filtration process, removing 99% of contaminants from hard water entering your house. Its easy installation comes with instructions and even videos so that you can insert it under an average kitchen sink, or even mount it for your shower and bath. The filters included are premium and long-lasting, making it so you spend less on changes and so that your system gives you clear and healthy water longer. Making this purchase ensures top of the line quality for a medium price, excellent for nicer homes in big cities.
More features: 100% lead-free parts
When there are over 1000 water pollutants in your regular tap water, it’s hard to catch them all, but this product with its 5-stage filter system actually guarantees that it will. Eliminating chlorine, iron, arsenic, sulfates and nitrates, and any other contaminants you can name, this is a high-end system for a very low price. Fittings are used to make installation easy, and technical support is always on call for any questions. Once installed, it will filter around 99% of all contaminants without changing your water pressure or limiting how much water you regularly use a day. This point of usage system is built for installation under your kitchen sink or even where the water enters the room for your bathtub, shower, and other appliances (including the refrigerator). Stages 1-3 remove all chemicals, smells, and inorganics, and the last stages eliminate all hard water minerals. What comes out of the tap is crystal clear heaven.
If you haven’t used or even heard of a reverse osmosis system before, then you’ll probably have a lot of questions, such as when would you need one? Should you only get one for your sink, or should you get one which filtrates the whole house? In the remainder of this buying guide we provide advice on common concerns which people have about their water and how to clean it, or if they even need to clean it. We also provide advice on the type of system to buy, what dimensions will work best for your kitchen, etc.
The way reverse osmosis systems work is by using semipermeable membranes (picture a strainer), sometimes multiple membranes, attached at a water source to separate the dissolved inorganic solids (salts, irons, lead, pesticides, nitrates, and other) which are contaminating your water. With these removed, your purified water then tastes better and it actually becomes better for your health. These systems come with easy instructions and are generally very simple to install at point of use areas in your house. Devices are installed and can be attached where the water comes out (these are point of use systems; POU) at your sink, fridge, or even bathtub and shower. Some of these devices are specifically designed to attach at where the water enters the house by tying into your main water line, usually in the garage (these are point of entry systems; POE), and they purify the water throughout your entire household.
At first this might seem like it’s a matter of opinion, whether you want to purify all the water in the house or just the water in the kitchen. However, it’s not just the water from the kitchen or refrigerator that’s going to affect you. Our skin and hair also absorb the hard metals in bath and shower water, and if you live in an environment where the water is especially contaminated, then you might want to consider filtrating all hard water being used in your house. In the bathroom, you also brush your teeth, wash your face, and rinse, and all of these activities leave remaining chemicals and metals in your system.
If you don’t know the composition of your water (unfiltered) purchase PH strips and test it yourself. Safe water has a PH between 6 and 7.5, any higher or lower can mean that there are chemicals, irons, bacteria, and even pesticides. These elements seep in through ground water, breaks in pipes, or just don’t receive enough purification from the city. Also, in small amounts these might not be deadly, but when you use this water to wash a wound, or fill up a bottle to make baby formula, even the small particles can be dangerous to one’s health.
You might just want to consider a whole house filtration system.
Not any filter will do, especially if you want to pick one that will suit your household and preferences and needs of those living in it. For instance, the number of stages in a reverse osmosis system can majorly affect the taste of your water as well as your meals. Most 6 stage systems will add good minerals back into your water, not only improving the taste but also improving the health value of the water. A great example of a 6-stage system is the iSpring RCC7AK, it’s actually very cheap for such a high caliber system and it not only purifies your water but adds the good minerals back in. Other features might also make a big difference to you and your family, such as how much water a system will waste making one clean gallon for a bath, or how often you’ll have to replace parts/clean your system, if the contamination reduction will go down over gradual usage. These are all factors which will make or break a decision to buy a whole house filtration system, and each one is worth considering.
As discussed above, this feature can be the most important for you to analyze. Lower filtration stages (5 or less) will usually change the texture, look, and taste of your water. Many people think the taste is clean and pure, but maybe not as natural as mineral waters you’d get from a pure water spring. Some systems think of this and add back in slight minerals or taste to improve their water, such as the very affordable Express Water RO5DX. The more expensive processors (such as the Home Master TMAFC-ERP) provide multiple stages so they don’t have to re-flavor their water, instead, the last one or two stages always add good minerals back in before letting it flow to the tank and out the tap into your cup.
What dimension works for you is going to depend on your sink. Before making a purchase, go grab your tape measure, or your neighbor’s tape measure, and go into your kitchen to the sink. Or go to wherever you intend to install the system. Next measure the space to see how much room you have. One of the most space-friendly models is the iSpring RCC7, which not only mounts to wherever you want it, but also has a large enough capacity to hold the water you need in a given moment.
Don’t just buy any filtration system that you see online, make sure first that they are rated and certified by the NSF. If you see this certification it means that the reverse osmosis system actually does a good job of purifying the water, disposing of the waste, and delivering a healthier product. Bonus certifications you can consider are from the FDA – usually for the clean holding space of the tank – and seeing them means that the product has been tested and approved to keep water fresh for long periods.
Additionally, look for systems that reduce 95% or higher of all contaminants.
Some filter replacement intervals can be very high; any systems which require you to change out filters twice yearly may end up costing more than they’re worth. Some filters can go up to $7.00 for just one, and most systems have 5-6 filters. If you have to replace each filter twice a year, that’s a lot of money which would be better spent purchasing a unit that requires less attention. One of the systems which lasts a long time without needing replacements is the APEC ESSENCE ROES-50.
Another option which might work great for you, are systems that come with replacement filters in the purchase. The less of these you have to buy, the better. Consider the great value Geekpure RO5 which comes at a cheap price but also includes 7 extra filters.
Flow rate isn’t the rate at which water pours out of your faucet, it’s actually the rate at which water passes through each membrane and is cleaned. The quicker this is, the better, because it’s that speed which forces the worst particles to get trapped behind. It also means that your tank will fill up more quickly, and that you’ll have more water available at a time.
The system with the best flow rate above (considering that most systems only have a GPD that’s 50-75) is the APEC ULTIMATE RO-90 which has a GPD of 90.
Companies which offer you a long warranty believe in their product, and that is always a good sign. For instance, Home Master TMAFC-ERP offers a five-year warranty, and so clearly, they believe that their product will hold up and purify your water for at least five years without any problem. Warranties also offers you some security in case the product shows up and breaks after a day, or some of the parts are already damaged.
Certifications are a good way to let you know that a product has been verified to work, and that it performs at or above the level it should. Check on each company’s product page to see the certifications they have.
Some extra features to consider:
Most systems are very self-explanatory and simple to install. On this list alone, none of them require the use of a wrench or threaded pipe. Instead, the majority of systems use sleeves and tube fittings. Make sure you get each tube fitting tightly coupled together to prevent leaks, and consult the instructions for the best way to position the holding tank. Tipping it sideways may gradually damage the tank and make it leak.
After installation most systems require that you test-run water through them for at least two full rotations. Most tanks hold 2.5 gallons of water, and so you’ll let tank fill and then you’ll run that water through the tap, then let the tank fill a second time.
Additionally, these eco-friendly units protect the environment from plastic waist, and extra features can be added to your system to recycle your water waste and use it for gardening. In a word, RO users will never have to purchase water bottles ever again.
Based on the parameters of our research, the best products are those which not only filter at least 99% of particles out, but also do it with little to no waste, without changing the pressure too dramatically, and without costing an arm and a leg. Therefore, the top three RO systems are:
iSpring RCC7AK For its extremely low and economic waste ratio of one pure gallon for every two waste, as well as its 99% filtration success and reintroduction of good minerals. Not only is this an amazing product, it’s comparatively cheap for its fine qualities. You will not find a better value system on the market.
Express Water RO5DX Not only is this the most budget-friendly system on the market, but it’s also extremely easy to install and will fit almost anywhere. It comes with a great 2-year limited warranty, meaning the manufacturers really trust their product, and includes four filters in the purchase. Over time this system will hold up better than others (filters only needing to be replaced once a year) and it will save you money on bottled water.
Home Master TMAFC-ERP This is the most trustworthy choice, with a 5-year warranty, and is also the best option for an entire household. It purifies larger quantities of water faster, and can be installed to filter water all over the house, including the kitchen and bathrooms. Not only does it clear 99% of hard particles and chemicals in regular tap water, but it also does so with the least amount of waste: a ratio of 1:1.5 if you purchase the additional pump.