How Much Does an Under sink Reverse Osmosis Cost?

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Are you interested in purchasing an under sink reverse osmosis system? Well, with its unique design and impressive water contaminant removal capabilities, it’s worth going for.

The price of an under sink RO system depends on several factors, including the size, brand, filter replacement, contaminants removal capacity, convenience, among others.

And do you know that the initial cost of an under sink reverse osmosis isn’t the only thing you need to consider? Yearly maintenance costs should also influence your purchasing decision.

Now that you’re looking forward to getting one for your home, you have to ensure that you get the best value for your money.

In this post, we’ll help you know the price you should expect to pay for an under sink reverse osmosis system today.

The Average Cost of an Under Sink RO System

The price of an under sink RO system depends on the type of filtration process it has and other additional features included like a permeate pump or booster, modular filter design, and iron pre-filter.

Most under sink RO systems feature a 5-stage filtration process with /without a pump. The most advanced systems include additional stages like UV light sterilization stages and remineralization.

That being the case, the average cost of an under sink RO system range from around $200 to $500. Commercial under sink RO systems’ price range from $500 and may exceed $1000.

Under Sink (With Tank) Reverse Osmosis Cost

Under sink RO water filters that come with a storage tank are usually the traditional type POU reverse osmosis systems.

An under-sink RO system costs between $200-$600 when it comes with a tank. You can actually get a high-quality under-sink system at the lower end of the mentioned price range. Check out the product listed below:

iSpring RCC7AK Under Sink RO System, Check Latest Price On Amazon

The iSpring RCC7AK is a reliable water filtration system that converts your tap water into pure, clean, and healthy drinking water by removing 99% of harmful contaminants like chlorine, arsenic, fluoride, lead, asbestos, and more.

RCC7AK features a beautiful European-style faucet and transparent housing for visual inspection. It boasts a complete filter pack that helps remove contaminants from your tap water. An alkaline remineralization filter restores healthy minerals to the water and an alkaline balance.

The system features a 3.2-gallon pressurized tank with a 2.5-gallon holding capacity. It is also easy to install and fits nicely under a standard kitchen sink.

Under Sink (Tankless) Reverse Osmosis Cost

Tankless under sink RO systems come with a higher price tag. The price range between $300 and $600.

With tankless systems, you pay more for the convenience of getting clean water instantly as opposed to tank-based systems. This is because, with one, you won’t have to wait for hours to fill the storage tank.

Interested in a tankless under sink RO system? Consider this unit:

Frizzlife PD600-TAM3, Check Latest Price On Amazon

Frizzlife PD600 comes in a tankless design and features a small footprint. It gets rid of 99.9% of water contaminants and produces the greatest tasting water.

The unit features an advanced water-saving technology and can save your water by up to 450%. It has a low drain ratio of 1.5:1 and a fast water flow of 600 GPD.

The system can also fill a 330ml cup in about 10 seconds. And since reverse osmosis removes essential minerals from your water, this unit restores them using an alkaline remineralization filter.

PD600 is easy to install, and filter replacement is also a breeze.

Installation Cost of Under Sink RO Systems

How Much Does an Under sink Reverse Osmosis Cost

Although under sink RO systems are a little tricky to install, you can still hack it if you have some basic DIY skills. It’s actually an excellent option for you if working with a tight budget or trying to save some extra bucks.

If you don’t have DIY skills, you’ll have to get a professional plumber to install the system for you.

The average cost for professional installation of an under sink reverse osmosis system range between $150 and $300.This cost applies when no modifications are needed for your existing plumbing.

If repairs or modifications need to be done, be ready to pay for additional charges, which can actually push the installation cost up to $400.

The installation cost usually includes labor, equipment, and all the necessary materials.

Maintenance Cost

In addition to the initial price of the under sink RO system, you’ll have to include the maintenance and operation cost. This cost is tied to the frequency of membrane and filter replacements.

The filter replacement depends on how heavily you use the system and on the quality of the source water. For instance, if your water is very high in sediment or chlorine, you’ll need to replace the filters more often.

Under sink filters can last between 6-12 months. This means that after every 6 months to 1 year, you’ll have to spend money on replacement filters.

The annual cost of filter replacement range from $60-$200, depending on the brand. The standard range is $80 to $100.

Also, note is that if the system you get for your home boasts more filtration stages, the expenses will be a little higher. Also, if the system’s filters come in a modular design, you’ll end up spending more.

Waste Water

As long as you’re using a reverse osmosis system, you can never avoid the cost of waste water. The great news, however, is that you’ll only notice a slight difference in your water bill if using a high-volume application.

Factors Affecting the Cost of an Under Sink RO System

  • System Efficiency

The efficiency of an RO system is determined by how fast it can produce water and how much waste water it sends down the drain.

Although all RO systems waste water during the water filtration process, many are far more efficient. They waste less water, and this makes them less costly in the long term.

Traditionally, most RO systems have filtered water to waste water ratio of 1:4. This means that for every 1 gallon of pure water produced, 4 gallons of water go down the drain.

These systems come at a lower price you’ll end up spending lots of money on them in the long run. However, nowadays, you can find under sink RO systems with improved ratios of 1:2 at the cost of around $200 to $300.

  • Filtration process

An RO system will cost if it comes with an above-average number of filtration stages. The more the stages, the more the cost.

A typical reverse osmosis system features 4 stage filtration processes. Such a system is capable of removing 99.9% of contaminants from the water.

However, an under sink reverse osmosis system features more than double the amount(sometimes up to 10+ stages). The more the stages, the more the filters. And the more the filters, the more money you’ll have to spend on replacements.

  • Brand

The price of under sink RO systems vary from brand to brand. Some brands, especially those that have been in the market for long, are just more expensive than others.

  • Certifications

Certified under counter reverse osmosis systems come at a higher price simply because customers can tell they’re reliable. Customers always look for the NSF certification (NSF/ANSI 58), the national standard for RO systems.

This certification indicates that the system has been tested and verified for efficiency. Other effective NSF certifications for RO filter systems include NSF standards 42, 58, 53,401, and P473.

  • Additional Features

Under sink RO systems can be purchased with lots of additional features. These add-ons include a permeate pump that boosts pressure, increases production capacity, flow rate, efficiency, and reduces waste water.

Other popular add-ons are remineralization filters that balance water pH and increase alkalinity and UV lamps.


If you want cleaner and better-tasting water free of contaminants, an under sink RO system is a great solution. When going for one, look beyond the initial price. Consider the installation as well as the maintenance cost of the system to have a precise estimate of the money you’ll be spending.