Looking for the most efficient water filtration solution for your home? Tankless RO systems are the latest filtration technology, combining convenience, space-saving designs, and top-notch purification.
Whether you’re dealing with hard water or simply want cleaner, safer drinking water. This guide covers the best tankless reverse osmosis systems of 2024, featuring comprehensive reviews, expert insights, and detailed pros and cons.
What is a Tankless Reverse Osmosis System?
In short, a tankless reverse osmosis system is an advanced water filtration system that purifies water without needing a storage tank. In traditional RO systems, filtered water is stored in a tank after going through the filtration process.
However, in a tankless system, water is delivered on demand, saving space and reducing the chances of bacterial growth and recontamination.
How does it work?
Water is pushed through multiple filtration stages, including a semi-permeable membrane, which removes contaminants like lead, chlorine, fluoride, and other harmful particles. Without a tank, tankless RO systems also help minimize water waste and are perfect for those who want a compact yet effective solution.
Why Choose a Tankless RO System Over Traditional RO?
Water Efficiency and Waste Reduction
One of the main reasons people are switching to tankless RO systems is their water efficiency. While traditional RO systems waste about 3 gallons of water for every gallon of purified water, tankless models often boast 1:1 or better water efficiency ratios. This means you save water and money on your water bills over time.
Compact Design for Modern Homes
Due to the bulky water storage tanks, traditional RO systems take up significant under-sink space. Tankless RO systems eliminate the need for these tanks, freeing up space and making them ideal for smaller kitchens or homes with limited cabinet space. The compact design perfectly matches modern homes, offering a sleek and efficient solution.
Maintenance and Filter Longevity
Since tankless systems don’t store water, the filters last longer, requiring less frequent replacements. Depending on your water quality, filters in a tankless system typically need to be replaced every 12 to 18 months. This longer lifespan makes tankless systems more cost-effective and easier to maintain than traditional systems.
Affiliate Disclosure: We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more›
Top 7 Best Tankless Reverse Osmosis Systems in 2024
Choosing the best tankless RO system can be tricky, but we’ve done the hard work for you. Below are detailed reviews of the top 7 models of 2024, evaluating features, pros, cons, and the best use cases for each. Before diving in, check the Tankless RO Systems reviews Comparison chart.
1. Best for Advanced Filtration: Stokk S1 Pro 8 Stage Reverse Osmosis Water Filter
The Stokk S1 pro is Ideal For Households looking for high-performance filtration with minimal water waste and a compact, space-saving design.
Pros:
- 8-stage filtration for thorough contaminant removal.
- Certified by NSF/ANSI and FCC for filtration quality.
- Tankless design, saving up to 75% of under-sink space.
- 600 GPD capacity with an efficient 2:1 water-saving ratio.
- Easy installation and automatic flushing to prevent sediment buildup.
Cons:
- Requires electrical power to operate.
- Drilling may be necessary for installation, which can be a limitation for some users.
The Stokk 8 Stage Reverse Osmosis Water Filter (S1 Pro) is a high-performance system that removes over 1,000 contaminants, including PFAS, fluoride, chlorine, TDS, and more. Its 0.0001-micron filtration precision eliminates 99.99% of harmful substances, delivering consistently safe drinking water. The 8-stage filtration includes activated carbon and coconut-shell carbon filters that improve the taste by reducing odors and chlorine.
The tankless design saves up to 75% of under-sink space, making it ideal for modern kitchens. With a 600 GPD capacity, the Stokk system offers a fast flow rate while maintaining an eco-friendly 2:1 pure-to-drain ratio, minimizing water waste. The system also features automatic flushing to prevent sediment buildup, extending the life of the filters and ensuring fresh water at all times.
Installation is quick, typically taking around 30 minutes, and the filters are designed for easy replacement with a twist-and-pull mechanism. This makes maintenance simple and hassle-free.
Price: $299.99 | Buy on Amazon
2. Best for Alkaline Water: OnlyPure Reverse Osmosis System with Alkaline Filter
OnlyPure is Ideal For Households or small businesses looking for alkaline water with enhanced hydration properties and a system that is both efficient and easy to maintain.
Pros:
- NSF/ANSI 58 & 372 certified for high water quality.
- 6-stage filtration with an alkaline enhancement for better hydration and taste.
- 600 GPD capacity for fast, uninterrupted water flow.
- Smart monitoring with real-time TDS and filter life display.
- Eco-friendly 2:1 water efficiency ratio.
Cons:
- Requires electricity to function.
- It may only be suitable for very hard water with pre-filtration.
The OnlyPure Reverse Osmosis System offers a 6-stage filtration process, providing clean, pH-balanced alkaline water. The system removes sand, rust, chlorine, and odors with pre-filters. The reverse osmosis membrane then filters out up to 93% of contaminants, including TDS, arsenic, lead, and other heavy metals. Finally, the alkaline filter enriches the water with essential minerals, delivering water with a pH level of 8.5+, which is ideal for hydration and overall wellness.
The system’s 600 GPD flow rate ensures a continuous supply of filtered water, making it suitable for both home and commercial use. Its tankless design saves space under the sink, and the 2:1 pure-to-drain ratio minimizes water waste, making it an eco-friendly and cost-effective option.
Smart features like real-time monitoring via a digital display on the faucet allow users to track TDS levels and filter life status. This makes maintenance easy and ensures the system continues providing high-quality water with minimal effort.
Price: $329 | Buy on Amazon | OnlyPure Reverse Osmosis System review
3. Best Budget-Friendly with Smart Features: SMONET Tankless Reverse Osmosis System (E600WA)
The SMONET is Ideal For Homes looking for a space-efficient, high-performance RO system with advanced filtration and smart monitoring capabilities.
Pros:
- Dual NSF/ANSI 58 and 372 certifications for water safety and performance.
- 7-stage filtration removes 99.99% of contaminants.
- Tankless design, saving under-sink space.
- 600 GPD flow rate with a 2:1 water-saving ratio.
- Smart LED faucet for real-time water monitoring.
Cons:
- Requires electricity to operate.
- Installation may be challenging in very tight spaces.
The SMONET Tankless Reverse Osmosis System (E600WA) is designed with 7 stages of advanced filtration, capable of eliminating 99.99% of impurities such as TDS, fluoride, lead, PFAS, chlorine, and other contaminants. The system is certified by NSF/ANSI 58 and 372 and guarantees high filtration standards and lead-free materials, ensuring water safety.
Its tankless design is space-saving and highly efficient, making it an excellent fit for smaller kitchens with limited cabinet space. The 600 GPD capacity allows fast water filtration, filling an 8 oz cup in just 8 seconds. The 2:1 water-saving ratio ensures that only one cup of water is wasted for every two cups of purified water, making the system eco-friendly and cost-effective.
The smart LED faucet offers real-time TDS levels and filter life monitoring, ensuring users always have access to clean, safe water. The system also includes automatic shut-off and auto-flush features, making it easy to maintain without constant supervision.
Price: $329 | Buy on Amazon | SMONET RO System Review
4. Best for Health-Conscious Users: TOKIT U2 Pro UV Reverse Osmosis System
TOKIT U2 Pro is Ideal For Medium to large households seeking a high-flow, low-maintenance system with the added benefits of mineral-rich water.
Pros:
- UV sterilization and advanced RO filtration ensure maximum safety.
- A strontium-rich remineralization filter enhances water taste and adds health benefits.
- Space-saving tankless design with a 600 GPD capacity.
- 2:1 pure-to-drain ratio for water efficiency.
- Easy filter replacement with a twist-and-pull design.
Cons:
- Requires more cabinet space due to the larger unit.
- It cannot be installed horizontally—it must remain upright.
The TOKIT U2 Pro UV Reverse Osmosis System combines the benefits of advanced reverse osmosis filtration with UV sterilization and alkaline remineralization, making it a versatile solution for households looking for clean, safe, and healthy drinking water. With a 600 GPD capacity, this system can filter water quickly, filling a glass in just 8 seconds. The 2:1 pure-to-drain ratio ensures high water efficiency, using less water than traditional systems.
In addition to removing 99.99% of harmful pollutants like PFAS, fluoride, lead, and even radioactive substances such as radium, the strontium-rich remineralization filter improves water taste. It adds beneficial minerals, resulting in a refreshing, mineral water-like flavor. This system is certified by NSF/ANSI 58 & 42, SGS, and FCC, ensuring filtration quality and user safety.
The tankless design saves up to 75% of under-sink space, preventing secondary contamination. With features like a filter life reminder and auto-flush technology, the TOKIT U2 Pro offers hassle-free maintenance, making it an excellent choice for households that prioritize both convenience and health.
Price: $399.99 | Buy on Amazon
5. Best for Compact Spaces: Vortopt R1 Reverse Osmosis System
The Vortopt is Ideal For Health-conscious individuals and families seeking a compact RO system that offers the benefits of remineralized, alkaline water.
Pros:
- 7-stage filtration with remineralization for alkaline water.
- Tankless design, saving space under the sink.
- Efficient 2:1 pure-to-drain ratio, reducing water waste.
- High 600 GPD flow rate, delivering fast water filtration.
- User-friendly installation and maintenance.
Cons:
- Requires electricity to operate.
- Additional pre-treatment may be needed for extremely hard water.
The Vortopt Reverse Osmosis System (R1) offers a unique 7-stage filtration process, including remineralization, which provides alkaline water with a pH level of 9.0. This system removes harmful contaminants like TDS, chlorine, and heavy metals and enhances the water with beneficial minerals, improving both taste and health benefits. This makes it ideal for individuals who want to improve circulation, boost immunity, and maintain a balanced pH level.
The tankless design saves space under your sink, making it perfect for compact kitchens. With a 600 GPD capacity, the system provides high flow rates while maintaining a 2:1 pure-to-drain ratio, ensuring efficient water use. The system’s installation is simple, with detailed guides and helpful videos. Filter replacement is also hassle-free, taking just seconds, which makes it an easy and efficient choice for busy households.
Price: $399.99 | Buy on Amazon | Vortopt Alkaline RO System Review
6. Best for High Water Demand: NexTrend 600 GPD RO System
NexTrend is ideal for homes with high water consumption looking for a compact, efficient, and technologically advanced water filtration solution.
Pros:
- Certified by NSF/ANSI 58 & 372 for high filtration efficiency and lead-free materials.
- 7-stage filtration for comprehensive contaminant removal.
- Space-saving tankless design with a high 600 GPD output.
- Smart monitoring with auto-shutoff for effortless operation.
Cons:
- Requires electricity to operate.
- Some users may find the 1.6 liters per minute flow rate too low for large households.
The NexTrend Tankless Reverse Osmosis System is a 7-stage under-sink filtration system for modern households. It effectively removes contaminants like TDS, fluoride, lead, and chlorine, ensuring safer and cleaner drinking water for your family. Certified by NSF/ANSI 58 and 372, the system is built with lead-free materials and reduces TDS levels by up to 99.99%.
With a capacity of 600 GPD, the NexTrend system delivers filtered water at a high flow rate, filling an 8 oz glass in just 8 seconds. The tankless design saves up to 70% of under-sink space, reducing the risk of secondary contamination from stored water. Additionally, the system operates at a 2:1 drain ratio, meaning it wastes only one cup of water for every two cups purified, making it a cost-effective and eco-friendly choice.
For ease of use, the system has an LED display faucet showing real-time TDS levels and filter status. The automatic shut-off mechanism and built-in flushing program ensure that the system remains clog-free and provides consistently fresh water.
Price: $439.99 | Buy on Amazon
7. Best Overall: Waterdrop G3 P800 Reverse Osmosis System
Waterdrop G3 P800 is Ideal For Larger families, businesses, or homes with high water demands looking for advanced filtration.
Pros:
- High output (800 GPD), suitable for large households.
- Efficient 3:1 water ratio that reduces water waste.
- Integrated UV filter for microbial protection.
- Smart faucet with real-time water quality monitoring via a TDS meter.
Cons:
- Higher upfront cost compared to other systems.
- Requires electricity to function.
The Waterdrop G3 P800 is a powerful 7-stage tankless reverse osmosis system that delivers 800 gallons per day (GPD), making it one of the highest-output systems available. It features an integrated UV sterilization stage, perfect for eliminating harmful microorganisms and ensuring safe drinking water—especially for homes using well water. The water goes through several layers of filtration, including carbon block and reverse osmosis membranes, to effectively remove 99% of contaminants like chlorine, lead, and fluoride.
In terms of performance, the G3 P800 boasts an impressive 3:1 wastewater-to-purified-water ratio, meaning it wastes only one gallon of water for every three gallons it purifies—making it one of the most efficient systems on the market. Additionally, the smart faucet has a TDS meter that provides real-time feedback on water quality and alerts users when it’s time to change filters.
The system is certified by the Water Quality Association with the Gold Seal, ensuring it meets high water filtration standards. The filters have a long lifespan, with the reverse osmosis membrane lasting up to 24 months, reducing the frequency of replacements and long-term maintenance costs.
Price: $999.00 | Buy on Amazon | Waterdrop G3 Review
Key Considerations When Choosing a Tankless RO System
Water Filtration Capacity
The first thing to consider is the water filtration capacity, measured in GPD (gallons per day). A family of four will need a system with at least 600 GPD to ensure a steady supply of purified water.
Filter Replacement Costs
Filter longevity varies between models, but generally, tankless RO systems require less frequent filter changes than traditional systems. Check the cost of replacement filters before buying, as some brands may have expensive replacement kits.
Well Water Compatibility
Not all tankless RO systems are designed to handle well water without additional pre-filtration. If you use well water, ensure your chosen system is compatible with pre-filters like sediment or iron filters.
Installation Requirements
Some systems are easier to install than others. While many tankless RO systems are designed for DIY installation, others may require professional help, especially those with advanced features like UV sterilization or smart faucets.
For best results, hire professional plumber or follow the manufacturer’s manual for any system-specific steps.
Additional Features to Look for in a Tankless RO System
Remineralization and Alkaline Options
Remineralization filters add back essential minerals like calcium and magnesium, improving water taste and pH. This feature particularly appeals to those concerned about the demineralization effects of RO systems.
UV Sterilization
Some high-end tankless RO systems come with built-in UV sterilization, highly effective at killing bacteria and viruses. This feature is essential for those who rely on well water.
Smart Features and Digital Monitoring
Modern tankless RO systems come equipped with smart faucets and digital monitors that show TDS levels and notify you when to replace the filters. These features make it easier to keep track of your water quality and system maintenance.
Noise Levels and Power Consumption
Tankless RO systems typically require a pump, which may result in some noise. While the noise level is usually minimal, it’s something to consider if you plan to install the system in a quiet environment. Additionally, tankless systems often rely on electricity, so ensure your home’s power supply is stable.
Tankless RO vs. Traditional RO Systems
Water Efficiency
Tankless systems are more water-efficient, boasting a 1:1 wastewater ratio or better. In contrast, traditional systems may waste up to three gallons of water for every gallon of purified water produced.
Space and Design
Tankless systems are compact and ideal for modern kitchens. They fit snugly under the sink and save valuable cabinet space compared to traditional systems with bulky storage tanks.
Initial Cost vs. Long-term Savings
While tankless systems tend to have higher upfront costs, they offer long-term savings due to their lower water waste and longer filter life.
Conclusion: Is a Tankless RO System Right for You?
Tankless reverse osmosis systems are an excellent choice for a compact, efficient, eco-friendly water filtration solution. Whether you have a large family or live in small spaces, tankless RO systems offer plenty of options to meet your needs. With high filtration efficiency, lower water waste, and longer-lasting filters, they are a modern, eco-conscious solution for clean, fresh water.
When selecting the right system for your home, consider factors like daily water output, filter replacement costs, well water compatibility, and installation requirements. Tankless RO systems are becoming increasingly versatile and user-friendly, from advanced features like UV sterilization to the inclusion of smart faucets with TDS monitoring.
By investing in a high-quality tankless reverse osmosis system, you not only ensure better water quality for your household but also contribute to more sustainable water use, making it a smart choice both for your home and the environment.
Final Verdict
If you’re looking for a system that excels in performance, the Waterdrop G3 P800 is a top pick for large families with high water demands. If you’re on a budget but want to maintain quality, the SMONET Tankless Reverse Osmosis offers excellent value. The OnlyPure Reverse Osmosis System is the ideal choice for those who prefer demineralized water.
Regardless of your chosen model, a tankless reverse osmosis system is a worthy investment that provides cleaner, better-tasting water while saving space and minimizing water waste. So, go ahead and make the switch to a tankless system today!
Hi, I’m Engineer Hm Jamal, founder of Green Mark Engineering. With 13 years in the home improvement industry, I’m passionate about creating sustainable, high-quality solutions for homes. My focus is on making your home improvement experience smooth and successful. Whether it’s a renovation or a new project, I’m here to ensure it’s done right.
