How Much Does the Reverse Osmosis System Cost?

The Reverse Osmosis systems are a great way to purify water in your home. If you want to have clean and delicious water for your family, it might be the right answer for you. There are options, though. And it’s easy to get confused when looking for the right RO system. Cost is usually among the top criteria when choosing a product.

So how much do whole-home reverse osmosis systems cost? Simple, countertop RO system can cost between $130 and $400. More capable, under the sink system will cost between $190 and $400. And the most capacious, Whole house systems are somewhere between $500 and $4000.

Why such a price difference and is it worth it? Let’s examine these questions in more detail.

Cost factors for different types of RO systems

The price of RO systems varies from one system to another. It mostly depends on these factors.

 Low priceHigh price
Filtration stages – the quality of waterOne to three stagesFour to five stages
Gallons produced per day – the quantity of water10+500+
Maintenance costsFilter change about every six monthsFilter change early
BrandLess known, lesser quality, no warranty.Well known, good quality, life-time warranty, customer support.

Whole House RO systems

Generally, the whole-house system will be way more capable and suitable for supplying water to a multiple number of taps through the house. Or even the small number of apartments. The technology behind this system takes more space. Filters and RO membranes are bigger and more durable. They might last longer than small, countertop filters, but will definitely be more expensive.

How much water do you need?

Apart from water quality, which is directed by filter quality and filtration stages, the production capacity of the whole house RO system is the main point.

It’s the amount of water it can purify, usually measured in GPD (gallons per day). Another important factor is the flow rate – how fast it can do it. It’s usually measured in gallons per minute. A simple whole house system, with moderate water purification capacity, will cost around $500.

If you have higher water demands, that can be greatly expanded with an addition of an atmospheric tank and delivery pump. Which will raise the price up to $1,500. Stepping beyond a household and entering a commercial field with even greater demands for water, the price will grow from $5,000 to $10,000.

However, if the household does not use an exceptional amount of water a whole house systems can be installed without a storage tank and a pressure pump. Making it more affordable.

How good water should be?

The number of filtration stages and the quality of filters vary greatly. When making choices about these things you should first know exactly the quality of municipal water that you’re getting in the first place. That informs the requirements for main parts and subcomponents.

The Pre-Filtering unit
May consist of one or more filters. This is the stage where incoming water is treated to remove dust, rust, sand, and other relatively large sediment particles. The pre-filters are a must to protect the RO membrane and allow it to do its job properly and for a long time.

The main filtering unit
It’s usually made of two separate activated carbon filters of different sizes. These filters remove Chlorine, Chloramine, Hydrogen sulfide, organic contaminants like herbicides, and other dangerous chemicals. These pollutants can be coming from the groundwater or municipal water sources.

The Reverse Osmosis Unit.Holds back up to 99% of the impurities present in water – heavy metals, salts, Nitrate, Fluoride, and other known contaminants.

The Post-Filtering unit
Usually made of one or more carbon filters. They are called ‘polishing filters’ and eliminate any possible taste from the purified water. This is usually done if the RO system has a storage tank installed. Since the water that stays for a longer period can develop a slightly flat taste. Get to know how RO water tastes if you’re wondering.

Remineralisation unit
Generally, RO water comes slightly lower in pH and very low in TDS (Total Dissolved Solids). This is normal and does not affect much, but if needed, the pH can be further altered to the desired levels. This could be beneficial for houses or businesses where water is used to prepare exceptional food and drinks.


It might sound strange, but not all water that enters the RO system will come out through the taps. Reverse Osmosis is a water purification technology that, if done poorly, can be notorious at wasting water. Luckily, when you choose the right system, with the right components, water wastage will be minimized.

Some water waste will be present because it’s used to discard what’s left after the final purification happens in the RO membrane. To make this process as efficient as possible, a pressure pump will be needed.

Smaller Whole house RO systems can get away with a wastewater ratio of 2:1. Meaning that for every gallon of purified water, two gallons will go to waste. Of course, your price for a water gallon dictates if that’s fine with you.

However, when water amounts increase, the wastage can become an issue. This can be mitigated by using a pressurizing pump and a recycle vale. Water will still be used to wash the RO membrane but the recovery rate can increase by 50% to 75%. And the waste ratio will turn to 1:3. Meaning for 3 gallons of purified water, only 1 gallon will go to waste.

Now we’re entering the territory of powerful, commercial RO systems, capable of producing up to 4000 gallons per day. Prices for such systems can range around $5000.

After doing the calculations of water prices and usage, the cost of a powerful RO system can actually end up saving money in the long-term. Nonetheless it’s a more sustainable way of consuming water.

Why and when would you need a whole house RO system?

Unless you already have a clear idea and you’re just doing research here are few ideas when you can consider the whole house RO system.

It purifies all the water coming into your home. So you can get clean and healthy water everywhere. You can drink it safely from every faucet. You can take showers for better-looking hair and skin, and wash your clothes with soft water.

If you have any devices such as whole-house humidifiers, you can safely plug them into the system. You can use RO water for watering plants.

Apart from home, commercial RO systems can be used in coffee shops, restaurants, barbershops, beauty salons, private clinics, and such. The professional, high capacity system can be beneficial for every business that needs high-volumes of excellent quality water.

All this might sound a lot. But truly there is a perfect RO system for every situation. You just have to know your water needs and have the right expectations. It’s no wonder that more affordable options that produce uncompromised quality water are also popular.

Under the sink RO systems

It’s a middle ground between Whole house RO and the most basic countertop RO systems. Under the sink, units are usually between $200 and $350. This system stays in the kitchen area and sits, as implies, under the sink in the cabinet. However, it’s possible to mount such units elsewhere. But not too far away from the water source and plumbing. Under the sink systems usually have a dedicated RO water faucet so a sink is needed.

How much water do you need?

If you need RO water solely as drinking water for the whole family then this might be the best option for you. Although it’s possible to connect under the sink unit to the fridge ice maker. And, also, to use RO water for cooking and brewing drinks. Usually, these units produce from 50GPD to 75GPD. Under the sink units have a water tank that ensures that you have water ready.

How good the water needs to be?

Again, that depends on the brand, the number of filtration stages, and incoming water quality. The most common are four-stage filtration systems with:

• Sediment Pre-filter

• Carbon filter

• Second filter

• RO membrane

However, it’s possible to get a system with a final polishing filter that gives water even better taste after it spends some time in the tank. A remineralization unit comes with the more expensive systems or can be added as an upgrade for some cheaper ones.

Wastewater factor

Waste to water ratio is somewhere between 3:1. Often it’s acceptable for smaller households with municipal water where the price per gallon is low. Alternatively, these systems are popular when people have private wells, where you don’t really pay for water at all. Wastewater greatly depends on incoming water pressure. The higher the pressure, the lower the waste. This can be altered by a permeate pump. It requires no electricity but increases the pressure towards the RO membrane and often drops the water waste ratio to 1:1.

The maintenance costs will be discussed later on. But overall they’re not huge and wary from $30 to $90 annually. If considered the amount of bottled water that an average household consumes, RO is a way more sustainable and cheaper option.

The cost also depends on the brand. Some of the well-known manufacturers are making and assembling everything in the US. I have picked the most noteworthy under the sink systems and compared them side by side.

Countertop RO systems

You can separate countertop RO systems into two categories.

• Best for someone who moves a lot has small water needs and is looking for cheaper options. That would be tankless systems that hook up to a kitchen tap.

• Best for someone who is willing to spend more, needs to provide drinking water for a modest number of people, and wants zero installation. That would be standalone units that need to be refilled with water.

The price for such countertop RO systems vary from $130 to $400 or even more.

How much water do you need?

Countertop RO systems, that have no tank, produce purified water on demand. They need a continuous water supply and always stand near a sink. These are usually the cheapest RO systems available. Don’t get me wrong, I’m not saying they are bad. These types of systems are simple, lightweight, and bare bones. Compared to others, they have low water production capacity, but the quality of purified water will be just as good as from more expensive systems. If your water needs are small it might be the best way to go.

Other types of countertop RO systems are freestanding units that do not need to connect to the sink. They usually have a water tank that needs to be removed in order to be filled with tap water and placed back. Some countertop RO systems are a crossover between water cooler and dispenser. Some can even produce hot water for drinks on demand.

They require zero installation and are easy to maintain. Because they are designed to look good and function easily it’s often a wise choice for water drinking at home, small office, or business location.

If that sounds like something you’re looking for, I have picked the most noteworthy countertop RO systems in this review and comparison article.

Maintenance and installation costs

Maintenance costs

All that being said, a standard RO system costs anywhere between $150 to $500. But that’s not all. There are maintenance costs that arise from changing filters and RO membranes when the time comes.

Each manufacturer has recommendations and standards of how long these components last and when they need to be changed. That also depends on the incoming water quality and overall water usage.

• Whole house RO systems can be serviced by yourself. Alternatively, professional maintenance will always be available for a price. It’s hard to estimate the price of maintenance.

• Under the sink systems are also made in a simple fashion and filters can be changed without much trouble. Most often filters are changed every twelve months and RO membranes every two years. The annual cost should be from $60 to $90.

• Countertop systems are made to be maintenanced in the simplest way possible just by swapping filters. The maintenance cost will vary based on water usage and the system itself.


Countertop RO system either is installation-free or there is a need to plug in a few water tubes and screw-on adapter over the faucet. It is quick and easy.

Under the sink RO systems are made to be installed within an hour or two. The process is simple and there are clear instructions. The tools required are simple and rudimentary DIY knowledge will be enough. However, it’s always possible to get a plumber to do installation. The prices will vary but it should cost from $100 to $400. Based on what additional fitting and plumbing work is needed.

Whole house RO systems are more complicated. The setup requires more time and additional materials like valves, tubing, gauges, and sometimes electrical installation. That increases cost and labor. Of course, if you have the skills and tools you can complete the installation yourself. Otherwise, a professional will be needed.

The cost is hard to guess because such systems aren’t standardized. It could be from $200 to $500 as a minimum. It’s best to get a consultation if you can, to avoid being surprised.

Is reverse osmosis worth the cost?

When talking about RO, we have the finest quality drinking water in mind. Based on your evaluated needs and expectations you should be able to pick the best RO system for you. Hope this makes your decisions easier and you will find the perfect system for your household or any other situation, where good water is needed.


This is my blog about the ways and solutions that can help you improve your health by taking more value from drinking water. As improving health means a lot to me, I decided to create the Water On Top project with the purpose to reveal the benefits of water, the finest products to take our daily water to another level, and much more great stuff about water that I believe is on top of our nutrition.

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