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The Best Whole House Reverse Osmosis Systems of 2024

Put simply, whole house reverse osmosis (RO) is the BEST OPTION to get a large volume of ultra-purified water throughout your home.

And if you are reading this article, then you must care about the quality of your water.

Whether it’s for you, your pets, or you have children in the house, it would be nice if you could trust that the water coming out of your faucet is safe for drinking, cooking, and bathing.

The best whole house reverse osmosis systems

It can be hard to know where to start when it comes to finding a whole house filtration system because there are so many options to consider.

That’s why we’ve compiled this list of whole house reverse osmosis systems! We hope that after reading through this post, you’ll feel much more confident in choosing which one is right for your home!

Whole House Reverse Osmosis Systems Overview

ProductTop FeaturesLearn More or Buy
FilterWater Commercial Reverse Osmosis System
FilterWater Commercial Reverse Osmosis System

  • 500 GPD

  • 2 RO Membranes

  • 2 Pre-filters standard

  • Multiple sizes available

  • Tank and pump available

US Water Systems Defender Whole House RO System
US Water Systems Defender Whole House RO System

  • 2,000 GPD

  • 3 RO Membranes

  • 1 Pre-filter standard

  • Multiple sizes available

  • Tank, pump, and UV included

iSpring RCB3P Reverse Osmosis RO Water Filtration System
iSpring RCB3P Reverse Osmosis Water Filtration System

  • 300 GPD

  • 3 RO Membranes

  • 3 Pre-filters standard

  • Pump included

  • Tank purchased separately

Whole House RO System Reviews

FilterWater Commercial Reverse Osmosis System

FilterWater 500 GPD Whole House RO System
FilterWater 500 GPD Whole House RO System

This filtration system from FilterWater is labeled as a “light commercial” but makes a great whole-house reverse osmosis solution for homes.

Systems are available in versions capable of processing from 200 up to 10,000 gallons per day (GPD).

The 200 GPD option offers separate sediment filters, a carbon block for chlorine, odor and VOC removal, a 5-stage granular activated carbon filter, and a high-flow reverse osmosis membrane.

FilterWater makes it easy to upgrade to a full solution with storage tanks in several sizes and an optional upgrade kit containing a digital TDS (Total Dissolved Solids) meter and a Concentrate Recycle Valve that recycles wastewater to achieve a higher recovery rate with less water loss.

If you qualify, FilterWater offers financing so you can spread the cost of your water reverse osmosis filtering system out over time.

Buy or More Info

US Water Systems Defender Whole House RO System

The Defender Whole House RO System
US Water Systems Defender Whole House RO System

The Defender is a whole-house reverse osmosis system that was built to be long-lasting, cost-effective, and ecologically beneficial.

This system is made in the USA and is made to remove all types of water pollution, including lead, arsenic, PFOA, and thousands of other harmful contaminants. 

High-quality components and parts including stainless steel housings, industrial pumps, reinforced connections, and standard UV disinfection makes this system highly dependable and easy to maintain.

A very efficient 5:1 waste water ratio, an excellent warranty, and many possible customizations mean you can count on this system to deliver consistent clean water.

Buy or More Info

iSpring RCB3P Reverse Osmosis RO Water Filtration System

The iSpring RCB3P is a whole-home residential or light commercial reverse osmosis water filter with a capacity of 300 gallons per day. Fluoride, calcium, arsenic, chlorine, salt, lead, and asbestos are all reduced by more than 99.9% by the system.

An included booster pump will speed up the purified water production. This is helpful if your house has low water pressure. There’s no storage tank included, which means you’ll need to buy one separately.

The RCB3P design is simple and straightforward, making it easy to install and change your filters.

The system is supported by a metal hanging basket and stainless steel frame, which serves as an additional protection layer for the equipment.

Keep in mind that this system is just a series of RO membranes. If your water needs additional pre- or post-treatment, those options will have to be purchased separately.

Buy or More Info

Whole House Reverse Osmosis System Buyer’s Guide

Reverse osmosis is just one of many water filtration system types. Both undersink reverse osmosis systems and non-RO whole house systems for municipal water or well water are also available and maybe a better fit for your needs.

How Does a Whole House Reverse Osmosis System Work?

Reverse Osmosis Membrane Diagram
Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane to remove ions, molecules, and larger particles from water.

A whole house RO system is installed at the point of entry (POE) for the water supply in your home, usually in the same location as your water heater.

This guarantees that all water entering your home must pass through your reverse osmosis system before it is available to the points of use (POU), such as appliances, sinks, and showers. All of the water in your home will show significant decrease in TDS, contamination, and chemicals.

The system itself consists of a series of filters, each designed to remove certain contaminants from the water.

The most important filter in an RO system is the reverse osmosis membrane. The RO membrane is an ultrafine filter that allows water to pass through but not any larger particles.

This process requires high water pressure, and the blocked contaminants are washed away in unfiltered wastewater.

Advantages of Whole House Reverse Osmosis Systems

There are many advantages to a reverse osmosis whole house water system.

Most Effective Water Filter Option

According to the Environmental Working Group (EWG), reverse osmosis water filters are the “most effective” way to filter your drinking water since they reduce or eliminate up to 99% of contaminants such as:

You may have specific water treatment goals to reduce fluoride, remove arsenic, decrease hard minerals, or protect someone who is sensitive to any contamination.

In any case, a reverse osmosis water filtration system is the most effective option!

Filters Your Entire Home

Whole house RO

As a whole-house system, you will enjoy clean, pure reverse osmosis water everywhere in your home.

Point of use (POU) reverse osmosis systems installed under the kitchen sink are a popular option if you only need filtered water for drinking and cooking.

However, if the quality of your water is low, then whole house units are a great way to get the benefit of RO water at every sink.

Improves Water Taste and Quality

Many people on city water prefer the taste of bottled water because of the chlorine taste they get from the tap.

Basic carbon filters may reduce chlorine, but RO will completely remove chlorine that will affect the taste and smell of your water supply.

Well water could be affected by many possible chemicals including organic contaminants, sulfur, or iron that make tap water less appetizing. RO will improve taste, remove water contaminants, and improve drinking water.

Improves Skin & Hair Health

Reverse osmosis purified water for bathing

Reverse osmosis systems don’t just create safe drinking water…

Chlorine and chlorinated by-products in shower and tub water can dry out skin and hair and affect people with common skin conditions.

If your main water line comes from a city water source, a whole home system will remove contaminants and water treatment by-products that affect you while bathing.

Increases Lifespan of Appliances

While whole house RO systems are not designed to handle very hard water, they will remove low to average limescale problems as well as iron and magnesium deposits.

These types of minerals and contaminants can build up over time in your washing machine, water heater, dishwasher, and plumbing fixtures. As appliances get blocked and/or corrode, they become less efficient and don’t last as long.

Disadvantages of Entire Home RO Systems


Unfortunately, whole house reverse osmosis systems are the most expensive filtration system option.

They require more parts and maintenance than standard (non-RO) whole house filters and produce waste water, which can add cost to your water bill if you rely on a municipal water supply.

Pre- or Post-treatment May be Necessary

As great as reverse osmosis systems are, they are not perfect at removing all types of contamination.

That is why they are often paired with a sediment filter, carbon filtration, a water softener, or other specialized filters that are more efficient for particular problems.

Pre-treatment of source water often includes the removal of sand, sediment, and silt that will age the RO membrane faster. Pre-filters need to be cleaned frequently when large particles are common in your water supply.

Water from wells and other natural sources may contain dangerous bacteria, viruses, or microorganisms that can make you sick. The RO membrane will block these but not destroy them.

For that, an Ultraviolet (UV) filter is installed to kill all microorganisms such as bacteria and ensure safe drinking water.

Water softeners (also known as a water conditioner or anti-scalant injection system) specialize in removing the natural minerals that create scale deposits including calcium and magnesium. A POE RO system will also remove these “hard water” minerals but is not as efficient as a water softener if the levels are high. A good water softener can be purchased separately or in combination with reverse osmosis systems.

Remineralization filters are another option if you think that the reverse osmosis system has removed TOO many healthy minerals along with the contaminants during the purification process. Adding some minerals back raises the pH and alkalinity of the water.

Waste Water

Unfortunately, wasting water is a normal by-product of reverse osmosis water filtration.

The exact amount of wastewater production depends on the efficiency of your system, the flow rates in your home, the strength of your water pump, and water usage.

For instance, if your system has a ratio of 4:1, this means that for every 4 gallons of pure water produced, 1 gallon of waste water containing the accumulated contaminants will be flushed down the drain. This equates to a 20% increase in water consumption not just for clean drinking water, but for everything you do in your home including running washing machines and flushing toilets.

Space Needed

A reverse osmosis water filter is not as efficient as other whole house filtration systems so they often cannot filter water as quickly as it is needed during high demand.

For this reason, RO systems require a storage tank to hold filtered water until it is needed. Since these tanks are often large enough to hold hundreds of gallons of water, you must have enough space in your basement or utility room for the reverse osmosis filter, storage tank, and possibly additional filters.

An undersink or countertop RO system with a dedicated RO faucet may be better if you don’t have the space.

Water Pressure Required

Low water pressure is a problem for an RO water filter system and a booster pump may be needed if the pressure of your water supply is less than 40 PSI.

In addition, you may need a pressure pump with a pressure gauge and a pressurized storage tank to ensure adequate flow of filtered water throughout the house.

Considerations When Purchasing a Point of Entry Reverse Osmosis System

Source Water Quality

A water test of your source water is always the ideal starting point since the chemistry of your water can vary depending on where your water comes from, how far you are from the local water treatment plant, and what sources of contamination are nearby.

Reverse osmosis can handle most contamination but if the pH level or hardness of your water is more extreme, additional filters may be necessary.

Water Consumption and System Sizing

The primary criteria for selecting an RO system is how many gallons of water per day (GPD) you expect to use for all purposes both inside and outside of your home.

Whole house reverse osmosis at all sinks

A good estimate of usage is 75 gallons per day (GPD) per person, so a family of four would want to look at options that can produce at least 300+ GPD.

However, you need to be sure to leave room for expansion or spikes of heavier than average usage. Heavy lawn watering, guests in the house, or other activities that use many gallons per day will lead to more capacity.

Many of our recommended systems can be scaled up to purify thousands of gallons per day to accommodate large homes or even support light commercial use.

These calculations will also factor into the size of the reverse osmosis water filtration system, as well as the storage tank, booster pump, and related supplies.

Water Pressure & Flow Rate

In a busy home that uses many gallons per day of tap water, you don’t want to see a large drop in water pressure after you install a reverse osmosis water filter system.

It is important to have adequate water pressure (and properly sized pumps and storage tank) to ensure that the purified RO water flows as fast as possible to the places it is needed.


Reverse osmosis systems may require a booster pump that can handle the volume of water being filtered and provide a steady flow rate to prevent pressure from dropping after initial filtration.

Booster pumps are typically rated in GPM or PSI, which stands for gallons per minute or pounds per square inch.

Filtration Stages

The number of stages in water filtration systems can vary depending on the size of the reverse osmosis water filtration system, and the unique chemistry of your water.

There are usually 2-4 core RO membranes in reverse osmosis systems and pre- and post-treatment filters will increase the total number of stages.

A water filter system with many more stages than a competing system isn’t always superior. The setup should always be selected to match the water quality and needs of your home.

Wastewater Ratio

The efficiency of reverse osmosis systems is measured in both the gallons per day it can process and in the amount of wasted water it produces.

The wastewater ratio is usually expressed as the number of gallons of purified water produced per one gallon of waste.

For example, water systems with a 5:1 ratio are more efficient than systems with a 3:1 ratio or 1:1 ratio.

If you pay per gallon for your water, this ratio is very important to the overall cost to run the system.

Storage Tanks

FilterWater Atmospheric RO Storage Tanks
FilterWater Atmospheric RO Storage Tanks

A water storage tank kit is necessary to store purified water produced by a reverse osmosis water filter system. The benefit of having a large reverse osmosis storage tank is that you will have immediate access to the purified water instead of waiting for it to filter through your reverse osmosis system in real-time.

There are two types of water storage tanks.

An atmospheric water storage tank is generally larger but has a lower GPH/gallon per hour flow rate and may require a booster pump for high-pressure delivery.

Pressurized water storage tanks tend to be smaller in size with a higher GPH/gallon per hour flow rate on their own.

Tanks can come in sizes ranging from 15 gallons up to 2000+ gallons depending on the size of your household, amount of water consumption, storage space, and reverse osmosis filtration system output.

It is always a good idea to select a tank that is slightly larger than you need for future growth. The larger the reverse osmosis system output, the larger your storage tank will need to be.

Installation & Maintenance

Even if you order your whole house water filtration system online to get a good price and hardware you can trust, they are generally not designed for a DIY (do it yourself) installation.

Most people will need to hire a professional plumber to install the system and may even want to pay a plumber to manage the regular system maintenance that is needed.

Ongoing Costs

reverse osmosis wastewater meter
Wastewater costs can add up with an RO system

There are two costs associated with maintaining a whole house RO system:

  • Replacing filters
  • Waste water

Filter replacements can be done by following a regular maintenance schedule set by the manufacturer or by monitoring the number of gallons filtered.

The quality of your water and rate of consumption will play a big part in determining the maintenance schedule as well.

Since the reverse osmosis process produces wastewater, it is important to estimate the amount your system will waste based on your average usage.

If you pay for municipal water (often both coming and going), there will be fees to flush this waste water out of the system.

Frequently Asked Questions

How Much Does a Whole House RO System Cost?

You can purchase a simple reverse osmosis filter for less than $1000, though the cost for a typical system with all necessary parts will be several thousand dollars.

A reverse osmosis system with pre- and post-treatment filters for a large house with high output needs can cost upwards of $10,000.

All systems are completely customizable to fit your needs and the requirements dictated by your water quality.

How Long Does a Whole House Reverse Osmosis System Last?

Whole house RO filters will typically last 15-20 years if it is properly maintained.

For it to last this long, you’ll need to perform regular filter changes, periodically test your source water for any changes, and seek help if the system does not perform as expected.

Do I need a whole house RO filter if I own a water softener?

A water softener (or water conditioner) ONLY works to remove or alter the minerals in water that cause “hardness” and limescale deposits.

Reverse osmosis works to remove ALL contamination and total dissolved solids from your water including some hardness minerals.

Depending on the quality of your water, you may need a water softener, a whole house water filter (like RO), or both.

Why is reverse osmosis water bad for you?

Reverse osmosis water is not bad for you… it is actually some of the purest filtered water you can drink without chemicals or contamination.

Some people believe drinking RO water all the time could be less than ideal because all of the natural minerals have been removed from the water and because RO water has a lower pH.

Read more about water acidity and RO water.

Is a Whole House Reverse Osmosis Unit Necessary?

Your needs, goals, budget, and water quality are all considerations when choosing a water filtration system.

Better tasting water can be achieved at the kitchen sink with an undersink reverse osmosis system for less cost than whole house water filtration.

Total dissolved solids and most contaminants can be removed throughout your home by a non-RO whole house water filter system with less cost and maintenance that whole house RO.

Do I Need Reverse Osmosis If I Already Have a Whole House Filter?

If you already have a non-RO whole house water filter, then you are doing great! Many whole house systems will remove many common contaminants from municipal or well water supplies and provide cleaner water throughout your home.

A whole house reverse osmosis system will remove even more contaminants including naturally occurring minerals for the purest possible water.

However, you must balance the higher cost and complexity of the system with your clean water goals.

Next Steps

purified RO water

If you have made it this far, you must be interested in the possibility of a whole house reverse osmosis system and the benefits of the purified water you will enjoy.

Here is a quick overview of the steps to take next:

  1. Consider the up-front cost, space requirements, and maintenance costs of whole house RO systems.
  2. Get water testing from a reliable laboratory so you know exactly what problems exist in your tap water.
  3. Contact one of the recommended vendors on this page and be sure to tell them that sent you! They will help you review the results of your water test and recommend the right solution.

A whole house RO filter is not the most affordable option among filtration systems, but reverse osmosis removes more contaminants than any other whole house filter.

If you want or need clean water purification that is second to none throughout your home, then a whole house reverse osmosis system is the way to go.