Dual flush toilets provide you the choice between two flush options, saving your overall water usage. The partial flush uses about half the amount of water as a full flush, resulting in water savings compared to other types of toilets.
Keep reading to get a better understanding of how the best dual flush toilets work, and reviews of our favorites!
Table of Contents
- Comparison of the Best Dual Flush Toilets in 2022
- Our Top Picks
- Dual Flushing Mechanism
- Dual Flush Button Explained
- Reviews of the 6 Top Dual Flush Toilets
- How Dual Flushing Works
- Introduced to the Market
- EPA Rating
- Single Flush vs. Dual Flush
- Advantages of Dual Flush Toilets
- Choosing the Best Dual Flush Toilet
- Installing a Dual Flush Toilet
- Bottom Line
Comparison of the Best Dual Flush Toilets in 2022
Our Top Picks
| • | Kohler Wellworth | |
| • | Most Water Efficient: | TOTO Drake |
| • | TOTO Drake + Washlet S500 | |
| • | Budget Friendly: | American Standard H2Option |
| • | Most Reviewed: | Swiss Madison St. Tropez |
| • | Runner Up: | TOTO Aquia IV |
Dual Flushing Mechanism
All toilets with dual flush technology have an improved system for flushing, allowing them to achieve very powerful and effective flushes with minimal water usage. Within the dual-flush toilets, there are two types of flushing technologies available – in other words, you could have a dual-flush toilet with either one of these types of structures:
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Pressure-Assisted Flushing
The first option is a pressure-assisted flushing structure, which uses a mixture of water and highly pressurized air. These systems are often more expensive and louder, but also more powerful.
-
Gravity Flushing System
The second option is a gravity flush system, which is more common than the pressurized ones. Such systems use gravity with water weight to produce the pressure for each flush. Gravity flush systems are also much quieter and water-saving compared to pressure-assisted options.
Dual Flush Button Explained
Reviews of the 6 Top Dual Flush Toilets
1. Kohler Wellworth – Editor’s Choice
- Flushing Score:
- Water Consumption: 1.1/1.6
- Bowl Shape: Round Front
- Flushing System:
- Flush Type:
- Style: Two-Piece
- Certifications: WaterSense
- Dimensions (sourced from manual): Toilet (27.75″ x 18″ x 29.25″), (12″), (2.12″), (15.25″)See image with dimensions
Performance Ratings
★ Easy to Install – 4.1 out of 5
★ Value for money – 3.6 out of 5
* based on Amazon’s rating system
Seat Options
- K-4639 Cachet® Quiet-Close™
- K-5589 Purefresh®
- K-76923 Puretide® Quiet-Close™ bidet
Product Documentation
Customer Reviews
Last gathered: April 17, 2022
- High-powered bulk flush system
- No splashbacks during flush
- Poor quality anti-leak valve
- Several clog complaints
Summary of Recent Reviews
This one has a powerful flush, according to several reviewers. For some, this was their first dual flush toilet and they wish they had bought it sooner. Customers like the modern look of this toilet, as it adds to the overall aesthetic of their bathroom. “Works Great and Looks Great!”
2. Toto Drake – Most Water Efficient
- Flushing Score:
- Water Consumption: 0.8/1.0
- Bowl Shape:
- Flushing System:
- Flush Type:
- Style: Two-Piece
- Certifications: ADA, WaterSense, CalGreen
- Dimensions (sourced from manual): Toilet (27.38″ x 17.31″ x 30.06″), (12″), (2.5″), (17.6″)See image with dimensions
Seat Options
- WASHLET®+ S550E
Product Documentation
Customer Reviews
Last gathered: April 17, 2022
- Bidet feature for better sanitary benefit
- High-powered cyclonic flush system
- A discouraging ridge design
Summary of Recent Reviews
Customers are pleased with this splurge! For most, this is a comfortable toilet with a modern design. Users like the bidet functionality and the ability to program simple functions such as opening the lid. “This Toto is amazing and the quality is top of the line. You can’t go wrong with a setup like this.”
3. TOTO Drake + Washlet S500 – Strongest Flush
- Flushing Score:
- Water Consumption: 0.8/1.28
- Bowl Shape:
- Flushing System:
- Flush Type:
- Style: Two-Piece
- Certifications: WaterSense, CalGreen
- Dimensions (sourced from manual): Toilet (27.38″ x 17.31″ x 28.88″), (12″), (2.5″), (16.37″)See image with dimensions
Performance Ratings
★ Easy to Clean – 4.6 out of 5
★ Easy to Install – 4.5 out of 5
★ Softness – 4.6 out of 5
★ Comfort – 5 out of 5
★ Value for Money – 4 out of 5
* based on Amazon’s rating system
Seat Options
- WASHLET®+ S500E
Product Documentation
Customer Reviews
Last gathered: April 17, 2022
- Self-cleaning features minimize the need for manual maintenance
- Relatively quiet but effective flush
- Automatic flush system for total hands-off experience
- Relatively more expensive
- Shallow bowl with low water level
Summary of Recent Reviews
Overall, this toilet is a perfect combination of functionality and enhanced design. It comes with many high-end features such as DYNAMAX TORNADO flush technology and the CEFIONTECT glaze.
When it comes to functionality, this toilet lets you choose between 0.8 and 1.28 flush, both of which utilize a 360-degree flushing system to successfully clear the whole bowl of waste. With this system, you will save approximately 3500 gallons of water per year without compromising on performance.
4. American Standard H2Option – Budget Friendly
- Flushing Score:
- Water Consumption (GPF): 0.92/1.28
- Bowl Shape: Round
- Flushing System:
- Flush Type:
- Style: Two-Piece
- Dimensions (sourced from manual): Toilet (27.75″ x 15″ x 30″), (12″), (2″), (15.75″)See image with dimensions
Performance Ratings
★ Easy to Install – 4 out of 5
★ Value for money – 3.9 out of 5
* based on Amazon’s rating system
Seat Options
- American Standard #5259B.65C Easy Lift Seat with Slow Close hinges
Product Documentation
Customer Reviews
Last gathered: April 17, 2022
- Excellent flushing performance
- WaterSense certification helps your water bill
- Seat is not included
Summary of Recent Reviews
Customers are happy with this dual flush toilet, stating that it has a powerful flush that does not clog easily. Buyers like this affordable, option that has a modern design. The comfort height is popular among users, adding additional comfort to your bathroom experience.
5. Swiss Madison St. Tropez – Most Reviewed
- Water Consumption: 1.1/1.6
- Bowl Shape:
- Flushing System: Vortex™ flush
- Style: One-Piece
- Certifications: WaterSense
- Dimensions (sourced from manual): Toilet (27″ x 15.12″ x 31.19″), (12″), Seat Height (16.5″)See image with dimensions
Performance Ratings
★ Easy to Clean – 4.4 out of 5
★ Easy to Install – 3.6 out of 5
★ Style – 4.5 out of 5
★ Comfort – 4.2 out of 5
* based on Amazon’s rating system
Seat Options
- Swiss Madison Quick-Release Seat SM-QRS54
Product Documentation
Customer Reviews
Last gathered: April 17, 2022
- Less noisy flush yet very powerful system
- Easy to keep clean, thanks to its flush system
- Splashbacks during flush might occur
Summary of Recent Reviews
While some users had trouble with tricky installation, most of them are happy with the sleek, modern design of the toilet, especially at this price. This toilet has a modern look, and the includes a soft-close seat. Several users praised the expedience of Swiss Madison customer service.
6. Toto Aquia IV – Runner Up
- Flushing Score:
- Water Consumption: 0.8/1.28
- Bowl Shape:
- Flushing System:
- Flush Type:
- Style: One-Piece
- Certifications: ADA, WaterSense, CalGreen
- Dimensions (sourced from manual): Toilet (28.25″ x 15.19″ x 28.12″), (12″), (2.5″), (17.6″)See image with dimensions
Performance Ratings
★ Easy to Install – 4.3 out of 5
* based on Amazon’s rating system
Seat Options
- SS124 SoftClose® Seat
- SS234 Slim Elongated SoftClose Seat
Product Documentation
Customer Reviews
Last gathered: April 17, 2022
- Clear instructions for ease of installation and maintenance
- Its low water level makes it difficult to maintain
Summary of Recent Reviews
Buyers love the sleek look of this one-piece toilet. Some buyers do mention that the water level is a bit too low for an effective flush, however, most customers are happy with this toilet. “Easy to clean without the molded curvatures at the base found in other models. No issues with flushing…”
How Dual Flushing Works
To understand how these systems work, we should first clarify how a siphon works, which is the main part of the dual flush toilet. A siphon is actually a flush valve that acts similarly to a plunger. When you press the flush lever to activate a full toilet flush, the siphon sucks water, sending it through a specific diaphragm into the siphon outlet. When the water reaches the outlet, gravity takes over and draws out the remaining water until the tank is empty.
So, how does a half flush work? Imagine a straw in a cup of water, but the straw only goes halfway into the cup. Once the water drops below the end of the straw, the straw won’t be able to suck any more water, and everything below that level will be unreachable. At that point, the straw will only be able to suck air instead of water, cutting off the water supply. This situation is actually very similar to how the dual flush mechanism works.
Most toilets achieve a half flush by breaking the water suction midway through the siphon action. Basically, the siphon usually has extruded cuts at the bottom which allow air to enter and break the air-tight seal. The breach in the seal results in emptying only half of the tank instead of the full tank. To understand in more detail, check out the video below.
Introduced to the Market
Dual flush toilets were designed mainly to save water. Since you only need to use 50% of the canister for a liquid flush, using a these toilets leads to significant water savings over time. And while they may seem like new technology, they were actually patented a long time ago.
The first system was developed by TOTO in 1960 and initially had two levers. It also came with a hand-washer, and the water from the hand-washer was reused for flushing.
However, the first practical implementation of a dual flush toilet was designed in 1980, with future iterations working to further decrease the water needed without compromising on flush performance.
EPA Rating
Overall, toilet companies are required to keep the flush capacity of their toilets below 1.6 gallons. Many manufacturers try to go below this requirement, with some toilets that are designed to only consume 1.28 gallons per flush. Toilets that are proven to flush effectively with 80% or less of the 1.6-gallon requirement qualify for EPA Water Sense certification. This certification ensures you save on your overall water consumption each month and can even include rebates on your water bill, depending on location. When considering a dual-flush toilet, look for EPA WaterSense certification if reducing water consumption is an important factor for you.
Single Flush vs. Dual Flush
The main difference between these two types of toilets is obvious – with a single flush toilet, you can’t choose the amount of water it uses during the flush. By comparison, they give the user the flexibility to choose a partial or full flush depending on their needs with each use.
Further, installing a dual flush toilet is an excellent long-term investment since it will save your family a decent amount of money and water over time. However, you should also know that pressing buttons on a dual flush toilet might require greater force, which might be an issue for elderly or disabled people. It also requires some initial learning to make sure everyone knows which button to use for a partial vs a full flush.
Advantages of Dual Flush Toilets
One of the main advantages of best dual flush toilets are they save money over time. It might not seem like a big difference, but imagine only needing half the resources for each flush to remove liquid waste. According to the American Water Association, an average person’s annual water expenses will reduce by about $250 by using a dual flush toilet. While toilets overall are built to consume less water with each use, they use the least amount of water when compared to any other type of toilet.Another advantage is that they are very environmentally friendly. According to the EPA, around 4,000 gallons of water can be saved each year in a standard household if a dual flush toilet is installed instead of a standard one.
Finally, another benefit that we should mention is that dual-flush toilets use gravity to force waste down a large trapway. Thanks to this design, you should experience minimal clogging with these toilets, meaning overall performance isn’t compromised even while you save on water.
Choosing the Best Dual Flush Toilet
Here are 4 factors to consider:
Seat Height
The height of your toilet plays a very significant role when it comes to comfort and convenience. Therefore, regardless of the type or design of your toilet, always consider the height.
Most standard toilets are about 15 inches away from the ground. However, there are many comfort-height toilets out there to choose from, which are typically ADA-compliant and around 18 inches in height.
Such design makes sitting on them feel like sitting on the average chair. The increased height and comfort makes these toilets a great choice for people with movement disabilities.
Durability and Warranty
Most units that include this flush system are well-known for their durability. Still, to ensure the quality of their products, most companies offer at least a 1-year warranty. It isn’t unusual for some companies to even offer an extended warranty, depending on the brand of your toilet.
In that period, buyers can return the product back to the company if it is faulty. If that happens, you most likely will be given a fresh replacement or free repair, depending on the issue.
Look for a durable model when investing in a new toilet, and if you’re very concerned about needing repairs, look for options with longer warranties as well.
Noise
Another thing to keep in mind while making a purchasing decision is noise. If you live with elderly people or kids, noisy toilets can make sleeping difficult. Especially if you have a baby, loud toilets can be a nightmare.
Quieter toilets usually have gravity flushes, which minimize the sound of each flush. On the other hand, air-pressurized models are often significantly louder. If you’re in a noise-sensitive environment, keep the type of flush in mind before selecting your new toilet.
Size and Shape
In terms of shape, there are two common types: elongated toilets and round ones. The elongated models are well-known for the comfort they provide. Their shape provides a better sitting experience than the round ones, although they do take up more space.
In comparison, round toilets are normally about 5 inches smaller and are a better option for kids. Finally, a third option particularly if you have less space,would be a wall-mounted toilet, which you can install easily in small bathrooms to maximize space.
Installing a Dual Flush Toilet
Installing them can be pretty simple if you have the necessary knowledge and tools. always check the installation guide for your specific model, but overall, here are the main steps to follow:
- First, remove the old toilet from its current place. You can use a knife or scraper to remove the old wax ring.
- Then, put the closet bolts from the new product over the flange.
- Now, using a masonry drill bit, drill through the floor over the screw-hole marks carefully.
- After that, screw both mounting blocks into the floor.
- Put the new toilet in its place and make sure it fits perfectly over the blocks.
- Open the toilet tank and remove the flush valve.
- Install the tank on the bowl and carefully tighten the bolts.
- After connecting the water supply line, you have pretty much finished the process.
- Finally, flush the toilet a few times to make sure there is no leakage.
Be sure to check our full guide on how to install a toilet
Frequently Asked Questions
The best dual flush toilets can be confusing to maintain and sanitize. Plus, if you accidentally press the wrong side of the flush, you may need to flush again.
Moreover, since dual flushing toilets have a separate flushing mechanism for liquid and solid waste, be prepared to change the flushing system completely even if the problem of faulty flush lies only in one small part breaking. While the flush mechanism has two buttons that can be pressed, their inside mechanisms are connected with one another, so you can’t repair one type of flush without needing to fix the other as well.
Absolutely. Compared to standard models, they save up to 67% more water, which can drastically decrease your water bills in the long term.
The minimum amount of water for a partial flush is usually around 0.8 gallons per flush. The maximum amount (full flush) is mostly between 1.28 and 1.6 gallons per flush. The models with 1.6 are usually more powerful than those with 1.28, although the 1.28 gallons per flush options minimize water consumption.
Various factors such as a faulty flapper or seal can cause the toilet to keep running. One factor that is often the cause is that the rubber piece might have misaligned. However, these issues are completely normal as the years go by, and are usually easy to resolve either on your own or with the help of a professional.
Bottom Line
It can be rather difficult to find the best dual flush toilet online without some knowledge. Therefore, we hope our buying guide and overall recommendations help out before you make your purchase! Ultimately, the Toto Aquia IV is our top pick if you want the benefit of the luxury features it has to offer. Alternatively, consider one of the other models from our list if you’re looking for a more affordable option.