TOTO WaterSense Certified Toilets: Complete List

EPA WaterSense is not a marketing label manufacturers apply themselves. It is a third-party certification program administered by the U.S. Environmental Protection Agency that requires independent testing at an accredited lab before any toilet can carry the blue WaterSense logo. To earn the label, a toilet must flush at 1.28 gallons per flush or less, clear at least 350 grams in the MaP flush performance protocol, and meet minimum bowl-cleaning standards. Those thresholds are the floor, not the ceiling, and TOTO clears them by a significant margin on every model in its current lineup.

TOTO was one of the first major toilet brands to push aggressively below 1.6 gallons per flush, and the data shows that early investment paid off. In independent MaP testing, where labs simulate real-world waste loads with a standardized soy-paste media, TOTO's G-Max, Tornado Flush, and Double Cyclone systems routinely score 800 to 1,000 grams. The WaterSense floor is 350 grams; TOTO's best models clear nearly three times that amount while using 20 percent less water than a standard 1.6-gallon toilet. For a broader look at how TOTO compares to Kohler, American Standard, and Woodbridge, see our guide to the best flushing toilets across all brands.

What Does EPA WaterSense Certification Mean for Toilets?

The WaterSense program launched in 2006 as part of EPA's broader effort to cut water demand without sacrificing product performance. For toilets, the program addressed a real historical problem: many early low-flow 1.6-gallon toilets introduced after the 1992 Energy Policy Act had poor flush performance because they simply used less water without changing the flush mechanism. WaterSense set a performance floor alongside the efficiency ceiling, so a certified toilet has to work, not just trickle.

Third-party labs that conduct the testing follow ASME A112.19.2 fixture standards and the MaP protocol published by map-testing.com. For each test, the lab packs soy-paste media into a simulated waste load and measures how many grams the toilet clears in a single flush. A toilet that fails to clear 350 grams in multiple test flushes does not qualify. TOTO's published scores, available on the MaP testing database and on the EPA WaterSense product search, consistently land at 800 grams and above, with several flagship models achieving the maximum 1,000-gram score.

Which TOTO Toilets Are EPA WaterSense Certified?

The table below lists the primary TOTO WaterSense certified models, their flush systems, MaP scores as reported in the MaP testing database, and configuration type. MaP scores shown are the full-flush test results. Scores listed as "1,000 g" indicate the toilet reached the maximum score awarded by the protocol.

TOTO also produces HET (High-Efficiency Toilet) variants in several lines that operate at 1.0 gallons per flush or 0.8 gallons per flush. These models carry the WaterSense label as well, since they fall comfortably below the 1.28-gallon ceiling. However, their MaP scores vary more than the standard 1.28-gallon models, and some of the ultra-low-GPF variants scored in the 600 to 800-gram range rather than at 1,000 grams. If you are choosing between a 1.28-gallon and a 1.0-gallon TOTO, the flush-performance delta is real and worth weighing against your water-saving goals.

How Does TOTO's Flush Technology Achieve WaterSense Performance?

Understanding the three flush systems helps explain why TOTO's WaterSense toilets outperform rivals that also meet the 1.28-gallon threshold. Water volume alone does not determine flush power. What matters is how fast the water enters the bowl, how it is directed, and how efficiently the siphon trap is activated and sustained.

The G-Max system, used in the Drake and Eco Drake lines, relies on gravity and a wide 3-inch flush valve, which is larger than the 2-inch valves found in many competing toilets. A larger valve opens and closes faster, releasing the tank water in a shorter, more powerful surge. Combined with a fully glazed 2.125-inch trapway, the system creates a strong siphon that pulls waste through decisively rather than trickling it. The result in MaP testing is a 1,000-gram score, meaning the toilet cleared the maximum load the protocol allows.

The Double Cyclone system, introduced with the Drake II, replaces some of the valve-size advantage with a motor-driven pump that accelerates water through two propulsion nozzles positioned on opposite sides of the bowl rim. The cyclone pattern the water creates rinses more of the bowl surface than a conventional rim flush while still activating a siphon strong enough for a 1,000-gram MaP score.

The Tornado Flush system, TOTO's most recent and most widespread technology, found in the UltraMax II, Aquia IV, Carlyle II, Vespin II, and Guinevere, eliminates rim holes entirely and replaces them with two large nozzles that direct water in opposing directions. The resulting centrifugal motion covers the full interior bowl surface, reduces the bacterial load at the rim where rim holes are hardest to clean, and maintains a 1,000-gram MaP score while enabling the dual-flush configurations used in models like the Aquia IV.

Do TOTO WaterSense Toilets Qualify for Water Utility Rebates?

Water utility rebate programs are one of the most consistently overlooked sources of savings when replacing a toilet. The EPA WaterSense program maintains a searchable product database at epa.gov/watersense that lists every certified toilet by manufacturer model number. When a water district creates a rebate program for high-efficiency toilets, it typically requires the toilet to appear in that database. Because TOTO lists every WaterSense certified model with its full model number, matching a specific Drake or UltraMax II to a rebate form is straightforward.

Rebate amounts are set by the local water utility, not by EPA. In drought-prone states such as California, Arizona, Nevada, and Texas, some utilities offer rebates up to $200 per toilet or even free toilet replacement programs for households upgrading from pre-1994 3.5-gallon or pre-1980 5-gallon models. In areas with moderate water stress, rebates in the $25 to $75 range are common. A household with two or three bathrooms replacing older toilets can recover a meaningful share of the purchase cost through stacked rebates.

For a deeper look at TOTO's model-by-model differences beyond WaterSense certification, the TOTO brand guide covers the full lineup including bowl shape, rough-in dimensions, and available color options.

How Do TOTO WaterSense Toilets Compare to Kohler, American Standard, and Other Brands?

Comparing WaterSense certified toilets across brands comes down to how each brand performs above the certification floor. The floor is 350 grams, and every certified toilet clears it. The question is how much headroom the toilet has above that minimum when you flush something that is not a standardized lab test.

Kohler's WaterSense certified lineup includes the Highline Arc and Cimarron, both reaching 1,000 grams in MaP testing. The Kohler Highline is one of the most widely installed toilets in the United States and benefits from a large installed base of owner feedback. American Standard's WaterSense roster includes the Champion 4 Max and the Cadet 3, with the Champion 4 Max achieving 1,000 grams and the Cadet 3 scoring in the 800-gram range. Both are solid performers at competitive positions.

Woodbridge's T-0001 dual-flush is WaterSense certified and carries a 1,000-gram MaP score at its full-flush setting, which is strong performance for the category, but Woodbridge has a shorter manufacturing history and a narrower service network than TOTO, Kohler, or American Standard. Swiss Madison's Chateau and Cadet carry WaterSense certification but MaP data is less comprehensive in the public database. Gerber's Viper and Avalanche series are WaterSense certified with MaP scores in the 800 to 1,000-gram range, representing a solid mid-market alternative.

Where TOTO consistently differentiates itself is not just in the MaP peak score but in the breadth of models hitting that score and in long-term owner feedback on clog frequency. Aggregated reviews on TOTO models show lower rates of repeat clogging complaints compared to the category average, which aligns with the flush-power data. For a side-by-side look at how TOTO measures up to Kohler specifically, the TOTO vs Kohler comparison breaks down each system in detail.

What Are the Best TOTO WaterSense Toilets for Each Use Case?

Choosing among certified TOTO models is largely a question of matching the toilet's configuration and secondary features to your priorities. Below are the top picks within the WaterSense certified lineup, organized by use case.

How Much Water Does a WaterSense TOTO Toilet Save Per Year?

The EPA's WaterSense program uses a household model of approximately five flushes per person per day to calculate annual water savings. At that rate, a single person using a 1.6-gallon toilet flushes roughly 2,920 gallons per year from that one toilet. Switching to a 1.28-gallon TOTO reduces that to 2,336 gallons, saving 584 gallons per person per year at the per-toilet level. Scaled across a four-person household with two bathrooms, that represents a meaningful reduction in annual water bills in markets that bill by volume.

The savings increase substantially when replacing toilets older than the 1992 Energy Policy Act. Toilets manufactured before 1994 typically used 3.5 to 5 gallons per flush. Replacing a 3.5-gallon model with a 1.28-gallon TOTO saves 12,775 gallons per person per year. That level of savings is why utility rebate programs exist and why TOTO's WaterSense certified lineup is a common recommendation in water-efficiency rebate literature.

For context on how dual-flush TOTO models like the Aquia IV extend these savings further, see our article on whether dual-flush toilets are worth it, which covers real-world average GPF calculations based on flush-type distribution in typical households.

Frequently Asked Questions

Are all TOTO toilets WaterSense certified?

Every toilet in TOTO's current North American lineup that operates at 1.28 GPF or less carries EPA WaterSense certification. TOTO discontinued its older 1.6-gallon standard-flow models in North America years ago. If you are purchasing a new TOTO toilet in the U.S. today, it will be WaterSense certified. Older TOTO models still in use that predate 1.28-gallon designs will not carry the label.

What is the MaP score requirement for WaterSense certification?

The EPA WaterSense program requires toilets to clear at least 350 grams in the MaP flush protocol. This is the minimum floor, not a performance target. TOTO's certified models consistently score 800 to 1,000 grams, which is two to three times the certification floor. A 350-gram minimum is considered barely adequate for light residential use; 800 grams and above is recommended for typical household demand.

How do I verify a TOTO model's WaterSense status before buying?

Go to epa.gov/watersense and use the WaterSense Product Search tool. Enter "TOTO" as the manufacturer and you will see a list of every certified model with its model number, GPF, and certification date. You can also search by a specific model number if you already know which toilet you are considering. This is the most reliable verification method because it pulls from the live EPA database, not manufacturer marketing materials.

Does the TOTO Aquia IV qualify for WaterSense rebates if it is a dual-flush?

Yes. Dual-flush toilets qualify for WaterSense certification if their full flush is at or below 1.28 GPF and the toilet meets the 350-gram MaP floor on the full flush. The Aquia IV's full flush is 1.28 GPF with a 1,000-gram MaP score, making it fully eligible. Most utility rebate programs that accept WaterSense certified toilets accept dual-flush models including the Aquia IV; confirm with your specific utility before purchasing.

What is the difference between TOTO G-Max and Tornado Flush in water efficiency?

Both the G-Max and Tornado Flush systems operate at 1.28 GPF in their standard configurations, so water use is identical. The difference is in how the water is used: G-Max uses a large gravity-fed flush valve, while Tornado Flush uses two angled nozzles to create a centrifugal wash pattern. Tornado Flush tends to clean the bowl more thoroughly per flush because it covers the entire interior surface, but both achieve the same WaterSense certification and 1,000-gram MaP score.

Can I get a TOTO WaterSense toilet through a utility free-replacement program?

Some water utilities in high-drought areas such as California and Arizona run free toilet replacement programs where they provide a WaterSense certified toilet at no cost to households replacing older high-flow models. TOTO models frequently appear on the approved lists for these programs because they are listed in the EPA WaterSense product database. Contact your local water utility or search for "free toilet replacement" or "WaterSense toilet rebate" on your utility's website to check eligibility.

Is the TOTO Drake or Drake II better for a WaterSense rebate?

Both the Drake and Drake II are WaterSense certified at 1.28 GPF and qualify equally for utility rebates that accept any WaterSense certified toilet. The rebate eligibility does not distinguish between flush systems or MaP scores above the certification floor. The choice between Drake and Drake II should be based on your bowl-cleaning preferences rather than rebate eligibility.

What does CeFiONtect (SanaGloss) do on TOTO WaterSense toilets?

CeFiONtect, marketed as SanaGloss in some markets, is TOTO's ion-barrier glaze applied to the ceramic bowl surface during manufacturing. It creates a microscopic smooth layer that reduces the adhesion of waste, bacteria, and mineral deposits to the bowl. Toilets with CeFiONtect require less frequent chemical cleaning to maintain a clean appearance. It is available on many TOTO WaterSense certified models including the UltraMax II, Aquia IV, and Drake II.

How does the TOTO Carlyle II compare to the UltraMax II for WaterSense performance?

Both the Carlyle II and UltraMax II use the Tornado Flush system, achieve a 1,000-gram MaP score, and carry WaterSense certification at 1.28 GPF. The primary difference is styling: the Carlyle II has a skirted trapway design with a fully concealed bowl exterior, while the UltraMax II has a more standard exposed trapway profile. Flush performance data is essentially identical between the two.

Do TOTO WaterSense toilets qualify for tax credits?

As of 2026, the U.S. federal tax code does not offer a direct residential tax credit for WaterSense certified toilet replacement. However, some state and local programs offer tax credits or deductions for water-efficient home improvements in drought-designated areas. Check with your state's department of water resources or a tax professional to confirm current availability in your area.

What GPF do TOTO's HET (High-Efficiency Toilet) models use?

TOTO's HET variants operate at 1.0 gallons per flush or 0.8 gallons per flush, both below the 1.28-gallon WaterSense ceiling. These models are also WaterSense certified. Their MaP scores vary more than the standard 1.28-gallon lineup, typically landing between 600 and 800 grams rather than at 1,000 grams, because moving less water through the same bowl geometry is physically more demanding.

How do I find TOTO WaterSense toilets that qualify for my utility's rebate?

Start at your utility's rebate page and note the specific requirements, usually WaterSense certified at 1.28 GPF or less and sometimes a minimum MaP score above 350 grams. Then cross-reference against the EPA WaterSense product search to find TOTO model numbers that match. Most utilities accept any model in the EPA database; some higher-rebate programs require 500 or 800-gram MaP scores, which narrows the field toward the Drake, UltraMax II, and Aquia IV.

Is the TOTO Vespin II WaterSense certified?

Yes. The TOTO Vespin II is WaterSense certified at 1.28 GPF and achieves a 1,000-gram MaP score using the Tornado Flush system. It is a two-piece toilet with a skirted concealed trapway design, giving it a cleaner side profile than a standard two-piece while sharing the same flush technology as the UltraMax II. It is a good option for design-focused bathrooms where a smooth exterior profile is preferred without moving to a full one-piece unit.

What rough-in dimension do most TOTO WaterSense toilets use?

The standard rough-in for most TOTO WaterSense certified toilets is 12 inches from the finished wall to the center of the drain flange. The Drake, Drake II, UltraMax II, and Aquia IV all have primary 12-inch rough-in versions, with 10-inch and 14-inch rough-in variants available for some models. Confirm the rough-in measurement of your existing toilet before ordering, as installing a 12-inch rough-in toilet in a 10-inch rough-in space is a common and avoidable installation error.

Does the WaterSense label on a TOTO toilet affect the warranty?

No. WaterSense certification is a product performance and efficiency designation; it does not alter or supplement TOTO's own manufacturer warranty. TOTO's standard warranty covers the china fixture itself for one year against defects; some components like flush valves and fill valves have separate coverage terms. Check TOTO's current warranty documentation for the specific model you are purchasing, as terms vary by product line.

How does a TOTO WaterSense toilet compare to Kohler's WaterSense models?

Both TOTO and Kohler offer WaterSense certified models with 1,000-gram MaP scores at 1.28 GPF. The Kohler Cimarron and TOTO Drake are the most direct comparisons. Both achieve the maximum MaP score and WaterSense certification. Kohler's AquaPiston flush valve technology and TOTO's G-Max produce similar real-world results, with preference often coming down to bowl shape, seat compatibility, and available colors. For a full head-to-head, see our TOTO vs Kohler comparison.

Are TOTO WaterSense toilets available in ADA-compliant heights?

Yes. The majority of TOTO's WaterSense certified lineup is available in Universal Height, with seat height of 17 to 19 inches from the floor, which meets ADA guidelines for accessible toilet height. The Drake, UltraMax II, Aquia IV, Carlyle II, Vespin II, and Entrada all have Universal Height versions. Confirm the specific model number includes the height you need, as TOTO model suffixes indicate height configuration.

How does the American Standard Champion 4 compare to TOTO Drake for WaterSense buyers?

Both the American Standard Champion 4 Max and the TOTO Drake are WaterSense certified at 1.28 GPF and achieve a 1,000-gram MaP score. The Champion 4 uses a large 4-inch flush valve versus the Drake's 3-inch valve; both produce equivalent MaP test results despite different valve sizes. The Drake has a longer service track record and broader parts availability through plumbing supply channels, while the Champion 4 is often available at slightly lower retail positions. See our best flushing toilets guide for a full multi-brand comparison.

Sources

• EPA WaterSense, epa.gov/watersense
• MaP flush testing, map-testing.com
• Manufacturer published specifications
• TOTO USA product documentation, totousa.com
• ASME A112.19.2 vitreous china plumbing fixtures standard