Brondell Circle Reverse Osmosis Review • (2024 Update)

Last updated Feb 15, 2024

Disclosure: As an Amazon Associate I earn from qualifying purchases.

Are you battling heavily-chlorinated municipal water or iron-rich well water? Perhaps you’d like to remove fluoride, chloramines, and everything under the sun from your tap water? Welcome to our Brondell Circle Reverse Osmosis Review. Reverse osmosis or “RO” systems are an excellent choice for removing everything from your water.

Standard under-sink RO systems usually come with a filtered water tank. The Brondell Circle is a unique tankless system that holds your filtered water inside the unit. Does that make it better? That’s what you’re about to find out in our review.

Let’s start by going over the core features of the Brondell H2O+ Circle RO Water Filter (RC100) before checking out what to expect from this system.

After that, we share our review and final score for the Circle. By the end, you’ll know for sure if the Circle is for you or if there are better options for your home.

Brondell H2O+ Circle RO Water Filter Overview

Model Features & Highlights
Brondell Circle Reverse Osmosis Water Filtration System (RC100)

Brondell Circle Reverse Osmosis Water Filtration System

Brondell H2O+ Circle Sediment and Carbon Replacement Filter Pack (RF-20)

Brondell H2O+ Circle RO Membrane Replacement Filter (RF-40)

  •  WQA Certified to Meet NSF/ANSI Standards 42, 53, 58, and 372 for Fluoride, Arsenic, Lead, Chlorine Removal & More!  (Lab Test Results)
  • Filter Life: Sediment Pre-Filter: 6 months, Pre-Carbon Plus Filter: 6 months, Post Carbon Block Filter: 6 months, RO Membrane: 24 Months
  • Filter Media: Activated Carbon Block, Sediment Pre-Filter, Reverse Osmosis Membrane
  • Warranty: 1-Year Warranty
  • Dimensions: 9.25” Width x 16.5” Height x 13.75” Depth
  • Weight: 14.6 lbs
  • Internal Tank Capacity: 6 liters or 1.58 gallons
  • Flow Rate: .26 to .37 gallons per minute
  • Operating Pressure: 40 – 120 psi
  • Highlights: Manufactured in South Korea (Not China) | Space-Saving Design | Installs below your sink | Includes attractive chrome faucet w/ LED filter life indicator | WQA Gold Seal Certified | Reduces wastewater by up to 10x w/ patented Smart Valve | Flexible internal reservoir for consistent filtered water flow No electricity required | A lot easier to install than a standard under-sink RO system Automatically flushes RO membrane to prolong filter life BPA-Free
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What to expect?

Before we make our final determination for all products included on our site, we examine current info to identify the pros and cons of owning a product.

Here’s what we concluded after analyzing past and present Brondell Circle info:

  • If you currently own or previously owned an RO system with a filtered water tank, you may be let down by the flow rate of the Brondell Circle. You might want to consider cutting the Circle water lines to minimize the length for an enhanced flow rate, although we don’t typically recommend cutting the included lines since it can increase the risk of leaks.
  • Brondell Circle installation is as easy as it gets for an under-sink RO system. There’s no need to mount anything. Once you install the faucet and drain line, the system is basically plug-and-play.
  • You’ll most likely enjoy the taste of filtered water from the Brondell system, especially if your tap water has any funky tastes or odors. RO systems do an excellent job of removing impurities. The Circle has a post-carbon block filter to enhance taste and give the filtered water from the RO membrane a final scrub before it hits your glass.
  • Brondell connectors and valves are of higher quality than you’ll find with a budget RO system, which eliminates the need to worry about flooding your kitchen.
  • The reduced wastewater compared to a budget RO system is one of the Circle’s greatest advantages.
  • Keep in mind, the filtered water tank size is 6 liters. Once you empty the 6-liter tank, it takes 40 minutes for it to refill.
  • We found independent lab test results for Circle filtered water. The results matched the WQA results on the Brondell website. You can’t ask for much more as far as trustworthiness goes from a water filtration company.
  • Expect a large TDS drop in your tap water after running it through the Circle.
  • The LED filter indicator on the faucet works. The reason we wanted to point this out is that we’ve come across a lot of units with faulty indicators. The Circle doesn’t have that problem.
  • The filters are indeed easy to change.
  • Overall, the Circle reverse osmosis system performs well outside of potential slow flow rate issues.

Our Brondell Circle Reverse Osmosis Review

After investigating current info and examining this system ourselves, we’re excited to share our thoughts and award the Circle a final score. I broke our review into two parts: our likes and our dislikes.


  • There are enough complaints about the low flow rate to make it worth mentioning and noting before you buy.
  • We love reverse osmosis because of how powerful the filtration is, however, we prefer reverse osmosis with remineralization. You may want to consider installing an inline mineral filter cartridge as the final stage in your system to make your RO water alkaline. Why do this? Most people prefer the taste of alkaline water, and demineralized RO water is usually slightly acidic.
  • The 40-minute waiting period between tank refills may be a dealbreaker for large families or if you need more water on demand.
  • 4-stage filtration is adequate, yet it’s fewer stages than quality RO systems on the market that cost less. If you have iron-rich (rusty) well water and need heavy sediment reduction, there are better options with more frequent sediment filter changes than every 6 months.


  • First, we like that the Circle system and the Circle replacement filters (RF-20 and RF-40) are manufactured in South Korea rather than China. We have a lot of experience reviewing water filtration products manufactured in South Korea. Some of the best water filters in the world are made there.
  • The connectors, valves, and all parts of the Circle system are high-quality and worth the money.
  • The coveted WQA Gold Seal is the ultimate trust badge when shopping for a water filter. Brondell didn’t skimp when it came time to test and certify the Circle system for contaminant removal. The Circle removes fluoride, chlorine, arsenic, lead, chromium, chloramines, VOCs, and cysts at impressively high rates. You can be sure you’re drinking ultra-purified water from this system.
  • The annual replacement filter cost is reasonable, especially considering the filters aren’t made in China.
  • BPA-Free
  • Installation is quite easy for anyone. You may need assistance installing the drain clamp and faucet because the job requires drilling a couple of holes. We recommend watching the installation video below to see exactly how to install the Brondell Circle.
  • The reduced wastewater compared to standard RO systems is one of the best features of this system. Save money on your water bill and reduce waste. Inferior RO systems make entirely too much wastewater.
  • The LED filter life indicator is a feature you won’t find with all RO systems.
  • The space-saving design takes up considerably less room than a standard RO system with a tank.
  • Lastly, the automatic RO membrane flushing is a nice touch to keep the system running smoothly and efficiently.
We recommend the Brondell Circle Reverse Osmosis System to people who want comprehensive contaminant removal from municipally-treated water and well water that doesn’t require heavy pre-filtration.

Final Score: 8/10

Brondell Circle Reverse Osmosis Water Filtration System

Brondell Circle Installation Video

Before we wrap up our review, we want to show you how easy it is to install the Brondell Circle below your sink. The video below demonstrates how it’s done:

Annual Replacement Filter Cost

The 4-stage Circle system requires a filter change 2x per year and 1x every 2 years to replace the RO membrane (RF-40). There are 4 filters total in the system including the membrane.

There are currently 3-packs available of the sediment and carbon filters (RF-20) at Amazon #ad:

Brondell H2O+ Circle RO Membrane Replacement Filter (RF-40)

Overall, we feel the replacement filters are fairly valued, and you’ll certainly save money compared to buying bottled water.

Bottom Line

After previously reviewing the Brondell Cypress Water Filter and now the Circle system, we’re more impressed by the Circle and highly recommend it to people who are seeking a tankless RO system. RO system installation doesn’t get much easier than this, and the quality of the materials for the price is more than fair.

Keep in mind, a lot of bottled water is reverse osmosis water with minerals added for taste. Most people love having reverse osmosis water on tap at home, and the Circle makes adding a system to your home easier than ever.