4 Best Whole House Reverse Osmosis Systems (November 2023)

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Enjoy the benefits of reverse osmosis filtration throughout your entire home.

If you’re looking for a reverse osmosis system that can provide clean, purified water throughout your home’s plumbing and appliances, you’ve come to the right place.

We’ve shared our reviews of the best whole house reverse osmosis systems based on their performance, efficiency, customer feedback, longevity, and overall value for money.

🥇 Best Whole House Reverse Osmosis System

📊 Comparison Chart of Whole House Reverse Osmosis System

SystemUS Water Systems Defender
US Water Systems Defender Whole House RO System
Crystal Quest System
Crystal Quest Whole House Reverse Osmosis System
iSpring RCB3P
iSpring RCB3P
WECO HydroSense
WECO HydroSense Light Commercial Reverse Osmosis Water Filter System
Efficiency Ratio5:11:21:21:1
Production Rate2K – 8K GPD200 – 7K GPD300 GPD500 GPD
Tank IncludedYesYesNoNo
Pump IncludedYesYesYesYes
Annual Cost$200 – $800$300 – $400$130 – $140$100 – $1,000
Warranty2 years1 year1 year1 year

⭐ Reviews – Best Whole House RO Systems 2023

There’s one major reason why this RO system is number 1 on our list: its 80% efficiency rating. This system is more efficient than any other whole house reverse osmosis system we’ve reviewed, wasting just 1 gallon of water per 5 gallons of water purified.

Key Features:

  • 5:1 efficiency ratio – The Defender Whole House RO System has a high efficiency ratio of 5:1. For every 5 gallons of purified water produced, 1 gallon of water is wasted.
  • Customizable size & flow rate – You can choose from two storage tank sizes (140 gallons and 250 gallons) and 4 production rates (from 2,000 to 8,000 GPD; 2,000 GPD will be more than enough for most residential uses).
  • Durable build & good warranty – With high-quality components, including stainless steel housings (no plastic used here), the system has a good lifespan and a relatively decent 2-year warranty.
  • Several pre-treatment optional upgrades – The manufacturer recommends using a pre-treatment to ensure the Defender can last up to 20 years. You can choose between the Anti-Scalant Injection System and the BodyGuard Plus Whole House Water Filtration System, or both.
USWS Defender OptionsPrice (140 Gallons)Price (250 Gallons)
2,000 GPD$8,595$8,895
4,000 GPD$9,195$9,495
6,000 GPD$9,795$10,095
8,000 GPD$10,395$10,695

Best For:

Anyone who has a big budget and would rather spend more money upfront for the ongoing cost and water savings of the most efficient whole house reverse osmosis system available today.


  • We think the Defender Whole House RO System is leading the pack from a design perspective. It uses a commercial centrifugal pump, which has a much longer lifespan than common RO pumps like rotary vane and diaphragm pumps. Included is a flow meter and pressure gauge, so you can better control your water and wastewater production, and the 5-micron pre-filter helps extend the lifespan of the RO membrane itself.
  • The 5:1 efficiency ratio is the biggest selling point of this system. Comparable systems waste twice, or even three times, as much water as this. Using the Defender system in your home, you’ll be able to limit your wastewater production – essential in a point-of-entry system that will process a much greater volume of water than a POU alternative.
  • Like the best whole house reverse osmosis systems, the Defender can reject up to 99% TDS (total dissolved solids) – and it comes with a TDS meter, so you can check the efficiency of the system whenever you need to.
  • We appreciate having so many easily accessible upgrades and add-ons for different scenarios and water quality issues. You can upgrade to a permeate pump to increase efficiency, choose from various storage tank sizes and flow rates, and add pre-treatment systems to your upfront purchase, depending on your situation.
Pretreatment UpgradesPriceUses
Bodyguard Plus$1,300Chemical removal
Anti-Scalant Injection$600Scale prevention
Bodyguard Plus & Anti-Scalant$1,900Chemical removal and scale prevention


  • The unit is very expensive, especially if you purchased a pre-treatment system too.
  • We couldn’t find information on filter changes.

This system is less efficient – its efficiency ratio is 1:2 – but it comes in a greater range of sizes, including smaller sizes that are much more affordable and better suited for residential use. Made in the USA, each Crystal Quest system undergoes extensive testing in-house before being shipped to you fully equipped and ready to go.

Key Features:

  • 1:2 efficiency ratio – The Crystal Quest Whole House Reverse Osmosis System has an efficiency ratio of 1:2. That means for every 1 gallon of water purified, 2 gallons of water are wasted.
  • 11 system sizes & multiple configurations – You can select your system flow rate (from 300 to 7,000 GPD) and upgrade to a unit with a storage tank kit (including a 165-550-gallon storage tank), so there’s something for every situation.
  • 4-stage filtration – There are four filters that make up the system, providing conventional RO water treatment as we know it:
    1. Sediment Reusable Pleated Filter Cartridge
    2. The Coconut-based Carbon Block Filter Cartridge
    3. The SMART Filter Cartridge
    4. The RO Membrane
  • Optional add ons & extras – Crystal Quest sells a few additional water treatment systems that you can tack on to your initial purchase, including a UV sterilizer to prevent microbiological contamination, and an alkalizing post-filter, which increases water’s pH.
Crystal Quest ConfigurationsPrice
(w/ 165 gal. Tank)
(w/ 220 gal. Tank)
(w/ 550 gal. Tank)
300 GPD$2,227$3,907$4,107$4,507
400 GPD$2,527$4,207$4,407$4,807
500 GPD$2,883.65$4,563.55$4,807.51$5,208.76
750 GPD$2,983.65$4,663.55$4,907.51$5,308.76
1000 GPD$3,734.30$5,414.20$5,658.16$6,059.41
1500 GPD$4,162.30$5,842.20$6,086.16$6,487.41
1800 GPD$4,312.30$5,992.20$6,236.16$6,637.41
2500 GPD$4,590.30$6,270.20$6,514.16$6,915.41
4000 GPD$6,409.30$8,089.20$8,333.16$8,734.41
5000 GPD$7,051.30$8,731.20$8,975.16$9,376.41
7000 GPD$7,693.30$9,373.20$9,617.16$10,018.41

Best For:

Anyone with a smaller budget who’s looking for a whole home reverse osmosis system with a greater range of smaller size options/flow rates within a more affordable price bracket.


  • A major benefit of the Crystal Quest Whole House Reverse Osmosis System is that there are smaller, more affordable options available for folks who want them. If you can’t afford to spend $8,000+ on the Defender unit, spending around half this price on the 300 GPD Crystal Quest with the smallest tank might give you everything you need as a more affordable alternative.
  • Though it’s naturally bulkier as a whole-home system, this Crystal Quest unit is relatively space-saving compared to other whole house reverse osmosis systems on the market. All the filter stages are housed in a single, compact unit, and the components are easily accessible, making it easy to perform maintenance and change filters.
  • If you’re reassured by third-party certifications, you’ll appreciate that this RO filtration system uses Scientific World Products ISO Certified Components.


  • The base model for this system comes without a storage tank (something that, in our eyes, you can’t go without on a whole house reverse osmosis system). So the standalone unit is deceptively cheap, because you’ll have to spend an extra $1,500+ for the storage tank.
  • The 1:2 efficiency ratio isn’t great. It means 2 gallons of water will be wasted for every 1 gallon produced – and in a whole house system, the water waste will rack up fast.

This 300 GPD tankless RO system costs under $500 – pretty incredible, since the majority of similar systems cost in the thousands. It has all the essential performance features of a quality reverse osmosis system, too, including a 1:2 efficiency rate, and an included booster pump and pressure gauge.

Key Features:

  • Tankless with tank upgrades – The iSpring RCB3P has the space-saving benefits of a tankless, compact unit. You can also purchase an 11 or 20-gallon iSpring storage tank with the unit (recommended to prevent interruptions in water flow around your home).
  • 1:2 efficiency ratio – Like the Crystal Quest unit, this iSpring system has a 1:2 efficiency ratio. That means 2 gallons of water are wasted during the RO filtration process for every 1 gallon of purified water produced.
  • 300 GPD flow rate – There’s just one flow rate option for this system: 300 GPD, meaning that the unit can produce up to 300 gallons of purified water per day.

Best For:

Anyone who wants to spend as little as possible on a capable RO system for their whole home, and isn’t bothered about having the option of lots of configurations and add-ons.


  • Affordability is the reason why we think so many people are tempted by the iSpring RCB3P. It costs hundreds, not thousands, of dollars, and is a fraction of the price of the comparably sized Crystal Quest RO unit, while offering virtually the same features.
  • Installation is always more challenging for a whole house reverse osmosis system, but the simplicity of the RCB3P’s design definitely helps matters. The filters are combined in a single unit, which is mounted on a metal hanging basket and stainless steel frame, making it easier to install the system and change the filters.
  • The 300 GPD flow rate is more than adequate for most households with 1-4 people, and the unit’s built-in booster pump increases the speed of purified water production. This is particularly helpful in homes with low water pressure that may struggle to handle a whole-house reverse osmosis water filter.


  • Again, we’re not sure about the tankless base model for this system. We always recommend buying a whole home RO system with a tank, which for this system costs around $200-$400 extra.
  • You don’t get the convenience and flexibility of upgrades/add-ons as you do with the other reverse osmosis systems on this list.

This compact, space-saving unit removes up to 98.5% of water contaminants and has a 1:1 efficiency ratio (better than the Crystal Quest and iSpring models). Its 500 GPD flow rate makes it ideal for households of up to 6 people.

Key Features:

  • 4-stage reverse osmosis process – The four stages of filtration offered by the WECO HydroSense allow for up to 98.5% contaminant removal. Combined, these filters remove particles like silt and rust, chlorine, chloramines, chlorine byproducts such as THMs, organic contaminants like insecticides and herbicides, heavy metals, salts, radon, fluoride, bacteria, and much more.
  • 1:1 efficiency ratio – For every 1 gallon of water produced, 1 gallon is wasted. That’s better than the 1:2 ratios of the Crystal Quest and iSpring models.
  • Pumps & sensors for efficient performance – The system comes with an automatic electric booster pump and pressure sensors, which work together to ensure the highest level of operating efficiency, regardless of your home’s water pressure.
  • Pre-assembled for easier installation – You don’t have to assemble this WECO unit from scratch, so the installation is relatively simple – and you can install the entire system using basic hand tools. However, the manufacturer advises that you pay a licensed plumber to install the system.
WECO HydroSense ConfigurationsPrice

Best For:

Folks who prefer to build their own whole home reverse osmosis system and want a quality, durable filtration system that they can combine with their own tanks, pumps, and other accessories.


  • Although not the cheapest we’ve seen, the WECO HydroSense is still pretty affordable at $1,500 (which includes the cost of the filters, housing, and pump – a storage tank isn’t included).
  • The 1:1 efficiency ratio is second-best on this list. If you want to waste as little water as possible but you can’t afford the super-efficient Defender system, the WECO HydroSense is the next best thing.
  • You might prefer the fact that you can buy your own tanks, pumps, and other parts alongside this RO unit, so you can build a system exactly to your tastes.


  • The WECO HydroSense isn’t a complete whole house reverse osmosis system. You’ll need to buy your own drinking water storage tank, jet pump and any additional equipment separately, which will add on to your upfront cost.
  • Some people struggled with the installation process due to unclear instructions and mismatched parts/fittings.

🧾 Whole House Reverse Osmosis System Buyer’s Guide

In this buyer’s guide, we’ve discussed everything you should know about whole house reverse osmosis units, including what they are and how they work, their advantages and disadvantages, and what to consider when buying a POE reverse osmosis system for your home.

What Is A Whole House Reverse Osmosis System?

A whole house, or point of entry, reverse osmosis system is a multi-stage water treatment system that’s installed at the location where your water supply enters your home.

Water flowing through the supply line will first pass through the reverse osmosis system before it branches out to different parts of your home.

How Does a Whole House Reverse Osmosis System Work?

Reverse osmosis works by sending water through a series of filters, including a semi-permeable reverse osmosis membrane.

Water particles are small enough to pass through the tiny membrane pores, but the majority of impurities are rejected and flushed down a drain along with a small amount of wastewater.

The water that leaves the reverse osmosis system is free from virtually all total dissolved solids, including chemicals, heavy metals, minerals, salts, microorganisms, and most other contaminants.

A whole house reverse osmosis filtration system has the benefit of being installed at the main feed water line into your home, so you can enjoy improved water quality in your pipes, fixtures, and appliances.

Closer look of the reverse osmosis membrane

👍 Advantages of POE Reverse Osmosis Systems

Let’s take a look at some of the biggest benefits of owning a whole home RO system:

  • Simple solution for entire home – Rather than buying separate filters, which will each require their own installation and maintenance, a whole house reverse osmosis system provides the benefits of multiple filters in one. You won’t need to invest in and maintain different filters at different points of use, like a shower filter for your shower water, an under-kitchen sink water filter for your drinking water, and a fridge filter for your refrigerator water.
  • Improved water taste – After installing a whole house reverse osmosis system, you’ll be able to enjoy clean, pure water from every faucet in your home. The RO purification process removes chlorine and other aesthetic impurities, eliminating poor odors that are associated with these dissolved solids.
  • Most effective filtration solution – We’ve tested dozens of different types of filters, and we can confidently say that there is no more effective filtration solution than a whole house reverse osmosis system. This water treatment unit can remove more than 99.99% of all total dissolved solids in your entire home’s water supply, greatly surpassing the contaminant removal abilities of a conventional non-RO whole-home filter system.
  • Increased appliance lifespan – By removing all trace minerals and impurities from water, a whole house reverse osmosis system can prevent the formation of limescale, sulfur, and iron deposits in your water-using appliances. This helps to sustain their performance efficiency and improve their longevity.
  • Improved skin and hair health – Whole house RO systems remove skin and scalp-irritating contaminants like chlorine, calcium, and magnesium, helping to improve your skin and hair health.

👎 Disadvantages of Whole Home RO Systems

Of course, there are also some disadvantages of whole house RO systems that you should also be aware of:

  • Expensive – Whole home reverse osmosis systems are the most expensive residential water treatment option available, with some units costing upwards of $8,000 (in comparison, a conventional non-RO whole house system costs around $1,000-$2,000). There’s also the long-term cost of filter changes and replacement parts to consider.
  • May require pre- or post-treatment – Alongside the cost of a whole house reverse osmosis system, you may also need to pay for a pre- or post-treatment system, such as a water softener before the RO system to prevent damage by hardness minerals, or a neutralizing filter installed after the system to bring the water pH back up to neutral.
ph scale
  • Wastes water – Whole house reverse osmosis units are usually more efficient than under-sink alternatives, but they still waste a lot of water. Most POE RO systems waste 1 gallon of water for every 2 gallons produced. So, if you use 300 gallons of water per day (about the average amount for an American household), your RO system would waste 150 gallons of water to produce this amount.
  • Take up a lot of space – All whole house RO water filter systems use a storage tank, which holds clean water, ready to be sent to faucets, fixtures, and appliances whenever needed. You’ll need enough room for this tank, which is usually large enough to hold 150-550 gallons of water, depending on the size you choose.
  • Requires adequate water pressure – A water PSI of at least 40 is required to install a whole house reverse osmosis system. If your water pressure is lower, you’ll need to purchase a pressure pump.

📌 Considerations When Purchasing a Point of Entry Reverse Osmosis System

Before buying a POE whole house reverse osmosis system, make sure to consider the following factors:

Your Budget

Start by considering how much you can afford to spend on a whole house reverse osmosis system.

The average upfont starting cost for a POE RO system is $1,000-$2,000 for the smallest unit. Depending on the size of your home and your required water flow rate, you may need to upgrade to a larger, more expensive system.

Some whole house reverse osmosis systems cost as much as $6,000-$8,000+, although these are usually intended for commercial use.

Also consider the ongoing costs of maintenance. Most reverse osmosis systems have at least two separate filter states and a semi-permeable membrane, which will need to be replaced every 6-24 months. The average annual cost of a whole house RO unit is $100-$800.

Source Water Chemistry

Your source water chemistry – i.e. its pH and the contaminants it contains – is another consideration to make.

Depending on your initial water quality, you might need to invest in additional treatment systems to protect your RO system.

For instance, if you have hard water, we strongly recommend buying a water softener to install before your RO system, which will protect the reverse osmosis membrane from scale formation. Or, if your water is sediment-heavy, install an inline pre-filter, like a sediment filter, to prevent sediment damage.

Water with an unusually low pH (a common well water issue) may also damage the membrane.

If you haven’t already, conduct a drinking water test to determine whether you need to install a pre-treatment system to protect the reverse osmosis membrane.

tap score water testing

Water Consumption

Whole house RO systems come in several sizes. Make sure to choose the right size for you based on your water consumption.

Assuming that you’re buying a reverse osmosis system for your home and not for commercial use, the smallest system will usually be fine for you.

You should still work out your average daily water consumption, which will help you determine the correct system size, storage tank size, and flow rate (discussed in more detail below).

You can use this handy water use calculator to get a rough idea of how much water you use. If you have a smart meter, simply take a reading at the end of the day for 7 days to get your average.

Water Pressure & Flow Rate

Make sure your water pressure is adequate for a whole house reverse osmosis system, and buy a system with the right flow rate for your water needs.

Normal water pressure is between 40 and 60 PSI in most US homes. 40 PSI is the minimum water pressure required to operate a whole house reverse osmosis system. You’ll need to consider a booster pump (at an extra cost of $100-$200) if your water pressure is inadequate.

As for flow rate, RO systems are measured in gallons per day (GPD). Smaller systems have a lower flow rate of 200-500 GPD, while larger systems for commercial use have flow rates from 1,000 all the way up to 8,000 GPD. For residential use, an RO water system with a 200-300 GPD flow rate is usually more than sufficient.


To effectively transport filtered drinking water from the RO storage tank to the point of use (i.e. a faucet, shower, toilet, or other water-using appliance), a demand pump is needed.

A demand pump switches on when there is “demand” for water (i.e. you switch on an appliance or open a faucet). This pump gives you fast access to water whenever you need it.

Most whole home reverse osmosis water filtration systems come with a built-in demand pump. If your RO water system doesn’t have one of these, you can buy one for less than $100.

Grundfos MQ3-45 Mark III pressure booster pump
Pressure booster pump
aquatec delivery pump
Demand pump

Filtration Stages

Take some time to learn about the different filtration stages in a whole house reverse osmosis system before you spend your money.

In a conventional reverse osmosis system, there’s a pre-filter, followed by an activated carbon filter, a reverse osmosis membrane, and a final activated carbon filter or post-filter.

Sometimes, a whole house reverse osmosis system might have several of the same filtration stages, such as two reverse osmosis membranes or two pre-filters, to provide thorough water treatment. While this is great for your water quality, it’ll increase the cost to replace filters.

Optional Remineralization Filters

Consider whether you want to install a remineralization filter downstream of your whole house reverse osmosis system.

Reverse osmosis systems filter everything out of your drinking water – and that includes healthy, taste-enhancing minerals, which can be found in most municipal water sources. You can reintroduce them to your water with a remineralization filter.

Of course, this will come at an extra cost. It’s also pretty hard to find remineralization filters that are suitable for whole-home use.

Acid neutralizing filters are more common, and they make the most sense for whole-home filtration. These water filters increase water’s pH, usually by adding dissolved calcium.

reverse osmosis remineralizing filer
Source: Walmart.com

Wastewater Ratio

An unavoidable side effect of the reverse osmosis water treatment process is water waste. Make sure to read up on a whole house RO system’s wastewater ratio before you click “buy”.

The more efficient the system, the less water it should waste for every gallon of water produced. Most whole house reverse osmosis systems have a 1:2 ratio, meaning that they waste 1 gallon of water per 2 gallons produced. The best systems have a 1:4 ratio, so they only waste 1 gallon of water per 4 gallons produced.

Regardless of efficiency, a POE reverse osmosis system will still waste more water than a smaller POU unit that only treats the water at one faucet. You’ll need to be comfortable with the inevitability of wasting water before buying a reverse osmosis system for your whole home.

Storage Tank Capacity

The average storage tank capacity for a whole house reverse osmosis system is 150-550 gallons. Make sure to buy a system with the right storage tank size for your water needs and your available space in the installation location.

From our own experience, we’ve found that the smallest storage tank size (usually around 150 gallons) is sufficient for the average family of 4. But if you have a large family or need the system for commercial use, you may need to size up.

The storage tank will refill with water whenever required, but the refill rate is slower than the rate at which you’ll use the water. The storage tank should be large enough to supply you with enough water to use consistently for any purpose, such as taking a shower or running a washing machine, without draining completely.

Let’s say your family of 4 uses around 300 gallons of water per day. In this scenario, a 150-gallon storage tank would only need to fully refill itself once daily.

whole house reverse osmosis water storage tank
Purified water storage tank

Installation & Maintenance

Make sure you’re aware of the installation and maintenance commitments of a whole house reverse osmosis system before you buy it.

Consider whether you want to install a POE water reverse osmosis unit yourself, or whether you’d rather hire a professional plumber. While some RO water filters are relatively easy to install, manufacturers generally recommend getting a plumber to do the job for you, to make sure you comply with your local area’s rules.

Most filters in a reverse osmosis system need to be replaced at least once a year, sometimes twice. This includes the pre- and post-filter, and the activated carbon filter(s). The RO membrane typically has a longer lifespan of 2 years.

Ongoing Costs

The biggest ongoing cost for a whole house reverse osmosis system is replacing the carbon, pre- and post-filters and the reverse osmosis membrane. On average, you’ll pay between $100 and $1,000 per year on replacement filters, depending on your system size and complexity.

Another ongoing cost to consider is the cost of water waste.

Let’s say, that your RO treatment system wastes 1 gallon of municipal water for every 2 gallons of filtered water produced.

If you used 300 gallons per day of municipal water in your home, you’d waste 150 gallons of water per day. You’d have a water bill for increased water usage – 450 gallons – even though you only used 300 gallons of that amount.

💡 Frequently Asked Questions

Can you get whole house reverse osmosis?

Yes, you can get a whole house reverse osmosis system. This is a pretty niche offering, so there aren’t many systems to choose from. However, a few manufacturers sell whole house reverse osmosis systems in various sizes for residential and commercial use.

Is a whole house reverse osmosis system worth it?

A whole house reverse osmosis system is worth it for you if you have a big budget and you want to remove as many impurities as possible from your entire home’s water supply. However, if you’re just looking to filter your drinking water or avoid the costs of drinking bottled water, you’ll get better value from a point-of-use reverse osmosis system, such as an under-sink system or a countertop unit.

How much water does a whole house reverse osmosis system waste?

The average whole house reverse osmosis system wastes 1 gallon of water for every 2 gallons of RO filtered water produced. Some systems are better than this – our top recommended pick in this guide, the US Water Systems Defender Whole House RO Water System, wastes 1 gallon of water for every 5 gallons of water purified – but they cost more upfront for this benefit.

How long does a whole house reverse osmosis system last?

The average whole house reverse osmosis system can last up to 15-20 years from installation – but only if you look after it properly. You’ll need to perform regular maintenance and protect the system with additional filters, like water softeners, to extend its lifespan.

  • Brian Campbell
    Founder, Water Treatment Specialist

    Brian Campbell is a water treatment specialist and water expert based in Denver, Colorado. He's always been obsessed with water quality, and has spent years testing all kinds of treatment devices from simple pitchers and portable devices to complex whole home systems.

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