Best Scandinavian Toilets (2026)
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Clean, low-profile silhouettes with real MaP-verified flush performance and efficient dual-flush water use, sized for a minimalist Nordic bathroom without sacrificing function.
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Water Efficiency Guide
How Much Water Does a Toilet Use Per Flush
Standard toilets use 1.28 to 1.6 gallons per flush (GPF). Older models can use 3.5 to 7 GPF. Here is exactly what you need to know about toilet water usage, including real-world flush performance, MaP scores, and EPA WaterSense certification.
Why Trust Best Flushing Toilets
- Flushing power and MaP flush-test scores
- Water efficiency (GPF and EPA WaterSense)
- Aggregated owner reviews
- Clog resistance and trapway design
- Brand reliability and warranty
Research updated June 2026.
Quick Answer
Modern toilets use 1.28 GPF (WaterSense certified) or 1.6 GPF (federal standard). Older toilets use 3.5 to 7 GPF. A family of four switching from a 3.5 GPF toilet to a 1.28 GPF model saves roughly 16,000 gallons of water per year. The key is finding a toilet that flushes powerfully at low water volume, which is where MaP testing and trapway design matter most.
What Is the Standard Water Usage for a Toilet Per Flush?
The current federal standard for toilets sold in the United States is 1.6 gallons per flush (GPF). Toilets that carry the EPA WaterSense label use no more than 1.28 GPF and must pass a flush performance test.
Toilet water usage has changed dramatically over the past 30 years. In 1992, the Energy Policy Act mandated that new toilets could not use more than 1.6 GPF. Before that, standard toilets used 3.5 to 5 gallons per flush, and some older gravity models used as much as 7 gallons. The shift to 1.6 GPF was controversial at first because early low-flow toilets often failed to clear the bowl in a single flush, leading to double flushing and customer frustration. Modern engineering has solved that problem. Today, a well-designed 1.28 GPF toilet can outperform an old 3.5 GPF model in both waste removal and clog resistance.
The EPA WaterSense program, launched in 2006, certifies toilets that use 1.28 GPF or less and meet rigorous MaP (Maximum Performance) testing standards. MaP tests measure the grams of solid waste a toilet can clear in a single flush. A score of 500 grams (about 1.1 pounds) is considered excellent. Most WaterSense toilets score 600 to 1,000 grams. This means you do not have to sacrifice flushing power to save water.
| Toilet Era | Gallons Per Flush | Typical MaP Score | WaterSense Certified |
|---|---|---|---|
| Pre-1994 (old standard) | 3.5 - 7.0 GPF | Not tested | No |
| 1994-2006 (early low-flow) | 1.6 GPF | 200 - 400 grams | No |
| 2006-present (WaterSense) | 1.28 GPF | 500 - 1,000 grams | Yes |
| Modern high-efficiency | 1.0 - 1.28 GPF | 600 - 1,000 grams | Yes |
How Much Water Does a Toilet Use Per Flush by Type: Gravity vs. Pressure-Assisted vs. Dual-Flush?
Gravity-fed toilets use 1.28 to 1.6 GPF and rely on water weight and trapway siphoning. Pressure-assisted toilets use 1.0 to 1.4 GPF with compressed air to force water into the bowl. Dual-flush toilets offer a 0.8 to 1.1 GPF liquid flush and a 1.28 to 1.6 GPF solid flush.
Understanding the flush mechanism helps explain why some toilets use more or less water. Gravity toilets are the most common. Water flows from the tank into the bowl, and the weight of the water creates a siphoning action that pulls waste through the trapway. These toilets typically use 1.28 or 1.6 GPF. The best gravity models, like the TOTO Drake II and American Standard Champion 4, use a large 3-inch flush valve and a glazed trapway to maximize flow with less water.
Pressure-assisted toilets, such as the Kohler Wellworth Pressure Lite, use a sealed tank that builds air pressure. When you flush, the compressed air pushes water into the bowl at high velocity. These toilets use less water (often 1.0 to 1.4 GPF) and are very difficult to clog. The trade-off is noise. Pressure-assisted toilets are louder than gravity models, which is why they are more common in commercial settings than in homes.
Dual-flush toilets give you a choice. A button or handle lets you select a low-volume flush for liquid waste (typically 0.8 to 1.1 GPF) and a full flush for solid waste (1.28 to 1.6 GPF). The TOTO Aquia IV and American Standard H2Option are popular dual-flush models. In practice, most households use the low-volume flush 70 to 80 percent of the time, which reduces overall water consumption. However, some dual-flush toilets have lower MaP scores on the low-volume setting, so it is important to check test results before buying.
Expert Take
Pressure-assisted toilets use the least water per flush while delivering the strongest flush performance. But for most homes, a gravity-fed WaterSense toilet with a 1.28 GPF rating and a MaP score above 800 grams is the best balance of water savings, quiet operation, and reliability. The TOTO Drake II is the benchmark here.
How Much Water Does a Toilet Use Per Flush Compared to Older Models?
Replacing a 3.5 GPF toilet with a 1.28 GPF WaterSense model saves 2.22 gallons per flush. For a family of four flushing five times per day per person, that is 44.4 gallons saved per day, or roughly 16,200 gallons per year.
The water savings are substantial. According to the EPA, the average home has 1.6 toilets. If every toilet in the United States were replaced with a WaterSense model, the country would save 640 billion gallons of water per year. For an individual household, the savings show up directly on the water bill. At the national average water cost of $1.50 per 1,000 gallons, switching from a 3.5 GPF toilet to a 1.28 GPF model saves about $24 per year per toilet. That number goes up if you are on a municipal water system with higher rates.
There is also a hidden cost of older toilets: double flushing. A toilet that cannot clear the bowl in one flush effectively doubles its water usage. An old 3.5 GPF toilet that requires two flushes uses 7 gallons per use, which is more than five times the water of a single 1.28 GPF flush. This is why MaP scores matter. A toilet with a MaP score of 800 grams or higher is unlikely to need a second flush, even with heavy waste loads.
If you are on a septic system, switching to a low-flow toilet also reduces the load on your drain field. Less water going into the tank means less frequent pumping and a longer system life. However, some septic owners worry that low-flow toilets do not provide enough water to move solids through the pipes. This is generally not a concern with modern 1.28 GPF toilets, especially if you use a model with a large trapway (2 inches or wider) and a high MaP score.
Which Toilets Use the Least Water Per Flush Without Sacrificing Performance?
The most water-efficient toilets use 1.0 to 1.1 GPF on the low-volume setting and 1.28 GPF on the full flush. Models like the TOTO Aquia IV, American Standard H2Option, and Kohler Highline Classic offer excellent MaP scores at these low water volumes.
Water efficiency is not just about the number on the spec sheet. A toilet that uses 0.8 GPF but requires two flushes to clear the bowl is actually less efficient than a 1.28 GPF toilet that flushes cleanly every time. This is why the EPA WaterSense program requires both a maximum water usage of 1.28 GPF and a minimum MaP score of 350 grams (though most certified toilets score much higher).
Below is a comparison of top-performing low-water toilets based on published specifications and MaP testing. These models represent the best balance of water savings and flush power available today.
| Model | MaP Score | GPF | Flush Type | Trapway | Height | Best For |
|---|---|---|---|---|---|---|
| TOTO Drake II | 1,000g | 1.28 | Gravity | 2-1/8" | 16-1/8" | Overall power |
| TOTO Aquia IV | 800g | 0.9/1.28 | Dual-flush | 2-1/8" | 16-1/8" | Water savings |
| American Standard H2Option | 600g | 1.0/1.6 | Dual-flush | 2-3/8" | 16-1/2" | Budget dual-flush |
| Kohler Highline Classic | 700g | 1.28 | Gravity | 2" | 16-1/2" | Reliability |
| American Standard Champion 4 | 1,000g | 1.6 | Gravity | 2-3/8" | 16-1/2" | Clog resistance |
| Woodbridge T-0001 | 600g | 1.28 | Gravity | 2-1/8" | 16-1/2" | Quiet operation |
Top Pick
TOTO Drake II
The TOTO Drake II is the most reliable 1.28 GPF toilet on the market, with a MaP score of 1,000 grams and a clog-free trapway design.
Flush TypeGravity (3-inch flush valve)
GPF1.28
MaP Score1,000 grams
Trapway2-1/8 inches
Height16-1/8 inches (rim height)
Pros
- Highest MaP score in its class
- Widely available parts
- Quiet flush
Cons
- Higher price point
- Standard height only
The TOTO Drake II uses the company's proprietary Tornado Flush system, which relies on two nozzles to create a centrifugal rinsing action. This design allows the toilet to clear the bowl with 1.28 GPF while maintaining a trapway large enough to handle heavy waste. In aggregated owner reviews across major retailers, the Drake II consistently receives high marks for not clogging and for keeping the bowl clean after each flush. It is WaterSense certified and meets all current efficiency standards.
The Drake II is also available in an elongated bowl with a Comfort Height option, which is ADA compliant. The 3-inch flush valve opens wider than standard 2-inch valves, allowing more water to enter the bowl quickly. This is a key design feature that makes low-water toilets flush effectively. If you want the best flushing toilet at 1.28 GPF, the TOTO Drake II is the standard.
Expert Take
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The TOTO Drake II is the gold standard for 1.28 GPF toilets. Its MaP score of 1,000 grams proves that water efficiency does not require sacrificing flush power. This is the toilet we recommend most often.
Bottom Line: The TOTO Drake II delivers the best flush performance at 1.28 GPF, backed by the highest MaP score and decades of reliable engineering.
Best Dual-Flush
TOTO Aquia IV
The TOTO Aquia IV uses 0.9 GPF on the liquid flush and 1.28 GPF on the solid flush, making it the most water-efficient dual-flush toilet available.
Flush TypeDual-flush gravity
GPF0.9 / 1.28
MaP Score800 grams (full flush)
Trapway2-1/8 inches
Height16-1/8 inches
Pros
- Very low water usage
- Sleek modern design
- Quiet operation
Cons
- Dual-flush mechanism can confuse guests
- Higher cost
The Aquia IV is TOTO's most water-efficient model. The low-volume flush uses just 0.9 gallons, which is less than a third of what an old toilet uses. The full flush uses 1.28 GPF and achieves a MaP score of 800 grams. This means you get genuine water savings without the risk of clogging. The toilet uses a standard gravity flush with a 3-inch flush valve, so it shares the same reliable mechanics as the Drake II.
Owner reviews note that the Aquia IV is very quiet and that the dual-flush button is intuitive once you get used to it. The bowl is fully glazed, including the trapway, which helps prevent waste from sticking. The Aquia IV is also available with a Washlet bidet seat, which adds to its efficiency by reducing toilet paper use. If your priority is minimizing water consumption, this is the best choice.
Expert Take
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The TOTO Aquia IV is the most water-efficient toilet that still flushes reliably. The 0.9 GPF liquid flush is among the lowest you will find in a residential toilet, and the full flush is strong enough for any waste load.
Bottom Line: The TOTO Aquia IV is the best choice for households that want the lowest possible water usage without compromising flush reliability.
Best Value
American Standard H2Option
The American Standard H2Option offers a dual-flush system at a lower price point, with a 1.0 GPF liquid flush and a 1.6 GPF solid flush.
Flush TypeDual-flush gravity
GPF1.0 / 1.6
MaP Score600 grams (full flush)
Trapway2-3/8 inches
Height16-1/2 inches
Pros
- Lower price than TOTO dual-flush
- Large trapway resists clogs
- Good water savings
Cons
- Full flush uses 1.6 GPF
- MaP score is lower
The H2Option is American Standard's entry into the dual-flush market. It uses a 1.0 GPF flush for liquid waste and a 1.6 GPF flush for solid waste. The solid flush uses more water than a WaterSense toilet, but the liquid flush is very efficient. The trapway is 2-3/8 inches, which is one of the largest available and helps prevent clogs. The MaP score of 600 grams on the full flush is adequate for most households.
Owner reviews are generally positive, with many noting that the H2Option is a good value for the price. Some users report that the liquid flush occasionally requires a second flush for larger liquid loads, but this is not a widespread complaint. If you want a dual-flush toilet on a budget, the H2Option is a solid choice. However, if you can spend more, the TOTO Aquia IV offers better performance at a lower water volume.
Expert Take
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The American Standard H2Option is a good budget dual-flush toilet, but the 1.6 GPF full flush means it does not qualify for WaterSense certification. For maximum water savings, the TOTO Aquia IV is a better investment.
Bottom Line: The H2Option is a capable dual-flush toilet at a lower price, but its full flush water usage is higher than the best competitors.
Frequently Asked Questions
How much water does a toilet use per flush in the US?
Federal law limits toilets to 1.6 GPF. Many modern toilets use 1.28 GPF and carry the EPA WaterSense label. Older toilets can use 3.5 to 7 GPF.
What is the average water usage per flush for a standard toilet?
The average toilet installed today uses 1.28 to 1.6 GPF. The average toilet in a home built before 1994 uses about 3.5 GPF.
How many gallons per flush does a low-flow toilet use?
A low-flow toilet uses 1.6 GPF or less. A WaterSense certified low-flow toilet uses 1.28 GPF or less.
Is 1.6 GPF considered low-flow?
Yes, 1.6 GPF is the federal standard for low-flow toilets. However, 1.28 GPF is now considered high-efficiency.
How much water does a dual-flush toilet use per flush?
A dual-flush toilet uses 0.8 to 1.1 GPF for liquid waste and 1.28 to 1.6 GPF for solid waste.
What does GPF stand for in toilets?
GPF stands for gallons per flush. It measures the volume of water used by a toilet in a single flush cycle.
How much water does a toilet use per flush if it is old?
An old toilet from the 1980s or earlier uses 3.5 to 7 GPF. Replacing it with a 1.28 GPF model saves significant water.
Does a 1.28 GPF toilet flush as well as a 1.6 GPF toilet?
Yes, if the toilet has a well-designed trapway and flush valve. The TOTO Drake II at 1.28 GPF has a MaP score of 1,000 grams, which is higher than many 1.6 GPF toilets.
How much water does a pressure-assisted toilet use per flush?
Pressure-assisted toilets typically use 1.0 to 1.4 GPF. They use less water than gravity toilets but are louder.
What is the most water-efficient toilet?
The TOTO Aquia IV uses 0.9 GPF on the liquid flush and 1.28 GPF on the solid flush, making it one of the most water-efficient residential toilets.
How much water does a toilet use per flush on a septic system?
Modern 1.28 GPF toilets work well with septic systems. The lower water volume reduces load on the drain field.
Does a toilet use more water per flush if you hold the handle down?
On most modern toilets, holding the handle down does not increase water usage. The flush valve opens fully and then closes automatically.
How much water does a toilet use per flush in a commercial building?
Commercial toilets often use 1.0 to 1.28 GPF and are frequently pressure-assisted to handle heavy usage.
What is the difference between 1.28 and 1.6 GPF toilets?
The difference is 0.32 gallons per flush. Over a year for a family of four, a 1.28 GPF toilet saves about 2,300 gallons compared to a 1.6 GPF toilet.
Sources
- EPA WaterSense, epa.gov/watersense
- MaP flush testing, map-testing.com
- Manufacturer published specifications
- American Society of Mechanical Engineers (ASME) A112.19.2 standard
- Energy Policy Act of 1992
Our Verdict
Toilet water usage has dropped from 3.5-7 GPF to 1.28 GPF without sacrificing flush power. The best toilets today combine low water volume with high MaP scores, large trapways, and reliable flush mechanisms. For most households, a 1.28 GPF WaterSense toilet like the TOTO Drake II offers the ideal balance of water savings and performance. If you want the absolute lowest water usage, the TOTO Aquia IV dual-flush model is the best choice. Replacing an old toilet with a modern high-efficiency model saves thousands of gallons of water per year and pays for itself in reduced water bills.
How we rank & our data sources
We do not run physical lab tests. Rankings are built from published, verifiable data and real owner feedback, never paid placement.
- MaP (Maximum Performance) flush scores
- EPA WaterSense certification & GPF ratings
- Manufacturer specifications (trapway size, flush-valve, rough-in)
- Verified owner reviews from Amazon, Home Depot & Lowe’s
Researched by Marcus Bell · Last updated June 30, 2026 · Our review method
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