TOTO UltraMax II vs Aquia IV

The TOTO UltraMax II and the Aquia IV are two of the toilets buyers cross-shop most often inside TOTO's mainstream lineup, and the reason is that they hit a similar price band while taking very different approaches to the same job. Both are 1.28-gallon WaterSense-eligible models built for ordinary bathrooms, both carry TOTO's CeFiONtect ceramic glaze and Universal Height bowls, and both wear the reliability reputation that makes TOTO a default recommendation. If you have narrowed your search to these two, you are not choosing between a good toilet and a weak one. You are choosing between TOTO's clean one-piece single-flush workhorse and its versatile two-piece dual-flush water saver.

The differences are real but specific. The UltraMax II is a one-piece, single-flush toilet engineered around a seamless skirted body that is easy to wipe down and a Double Cyclone flush that clears the bowl with a tight, efficient sweep. The Aquia IV is a two-piece, dual-flush toilet engineered around flexibility, with a 0.8 and 1.28 gallon button, a Dynamax Tornado flush and full compatibility with TOTO's WASHLET bidet seats. That single design philosophy ripples into water use, cleaning, price, install and style. This guide compares them head to head using published manufacturer specifications, MaP (Maximum Performance) flush-test gram scores, EPA WaterSense listings, flush valve and flush technology details, bowl heights and shapes, and aggregated owner ratings. For the broadest cross-brand ranking of flush strength, the pillar guide to the best flushing toilets covers TOTO alongside Kohler, American Standard and the rest. This page stays focused on the choice between these two TOTO lines.

Which TOTO toilet has the stronger flush?

Flushing power is measured most reliably by the independent MaP (Maximum Performance) test, which reports how many grams of solid waste a toilet clears in a single flush. Both of these TOTO models land in the same strong territory, around 800 grams on the full flush, which is comfortably above the 350-gram WaterSense minimum and well past what an average household produces in one flush. The difference is in how each one moves the water, not in the headline number.

The UltraMax II uses TOTO's Double Cyclone system, which feeds water through two angled nozzles instead of conventional rim holes, creating a centrifugal rinsing action that uses the full 1.28 gallons efficiently to sweep the bowl. The Aquia IV uses the newer Dynamax Tornado flush, which uses three nozzles to spin water around the bowl in a powerful swirl that improves rim coverage and bowl cleanliness. On paper the Tornado system has a slight edge in rinse coverage, which is why it earns the tinted cell on flush technology, but in terms of raw waste-clearing grams the two are practically even. Either toilet clears a normal load in one flush without drama.

Which TOTO toilet uses less water?

This is where the two toilets genuinely diverge. The UltraMax II is a single-flush toilet that uses a fixed 1.28 gallons every time you flush, which already beats the old 1.6-gallon federal maximum by 20 percent and earns it EPA WaterSense certification. For most homes that is plenty efficient, and the simplicity of a single lever has real appeal because there is nothing to think about and nothing for a guest to get wrong.

The Aquia IV is a dual-flush toilet with a two-button actuator on top of the tank. The light flush uses just 0.8 gallons and is meant for liquid waste, while the full flush uses 1.28 gallons for solids. Because most flushes in a typical home are liquid-only, the Aquia IV's effective average water use settles near 1.0 gallon per flush, which is meaningfully lower than the UltraMax II's flat 1.28. Over a year and across a busy household, that gap adds up on the water bill and can qualify for the same local utility rebates as any WaterSense toilet. If trimming water use is high on your list, the Aquia IV is the clear pick. For the full list of certified options across all brands, see our roundup of the best EPA WaterSense certified toilets.

Which TOTO toilet is easier to clean?

Cleaning is one of the strongest reasons buyers choose a one-piece toilet, and the UltraMax II is exactly that. Because the tank and bowl are molded as a single seamless unit, there is no gap between them where dust, hair and cleaning residue collect, and no awkward seam to scrub. Its fully skirted base hides the trapway contours that catch grime on conventional toilets, leaving a smooth outer surface you can wipe in seconds. Both toilets also carry TOTO's CeFiONtect glaze, an ultra-smooth ceramic finish that prevents particles and bacteria from adhering, so the bowl itself stays cleaner with less scrubbing on either model.

The Aquia IV is a skirted two-piece, which is a genuinely clean design by two-piece standards because its sides are smooth and the trapway is concealed. The one cleaning compromise is the tank-to-bowl seam, the joint where the separate tank meets the bowl, which is the spot most buyers think about when they picture wiping down a two-piece toilet. It is a minor difference in practice, but if effortless cleaning is a top priority, the seamless UltraMax II has the edge. For more on this trade-off across the catalog, our guide to one-piece vs two-piece toilets walks through the cleaning, price and install differences in detail.

Which TOTO toilet offers the best value?

On value, the Aquia IV is usually the winner. Two-piece toilets are generally less expensive to manufacture and ship than one-piece models, and the Aquia IV follows that pattern, typically landing below the UltraMax II on price while still delivering a strong 800-gram flush, dual-flush efficiency and TOTO's reliability. Add in the WASHLET+ design that conceals supply and power connections for a clean bidet upgrade later, and the Aquia IV gives you more flexibility per dollar. For a guest bathroom, a remodel on a budget, or any buyer who wants TOTO quality without paying the one-piece premium, it is hard to beat.

The UltraMax II costs more, and the premium buys the seamless one-piece body, the easiest cleaning of the two and the clean, modern silhouette that one-piece toilets are prized for. For a primary bathroom where look and effortless maintenance matter, many feel the step up is worth it. The choice is less about flush performance, since the two are nearly even there, and more about whether the one-piece styling and single-flush simplicity are worth the extra cost to you. We never quote prices here because they shift constantly, so check the current price on Amazon for the exact model and configuration you are considering.

What is a good MaP score for a toilet?

The MaP test was created to give buyers an objective, repeatable measure of flush strength instead of relying on marketing claims. It loads a toilet with a measured weight of test media and reports the maximum grams cleared in a single flush. WaterSense requires at least 350 grams to certify, which is the floor for an acceptable flush. In practice, anything from 600 grams upward handles a normal household with ease, 800 grams is genuinely strong, and 1,000 grams is the practical ceiling that the very best toilets reach.

Against that scale, both of these TOTO toilets are strong performers. Their roughly 800-gram full-flush scores clear a heavy load with margin to spare, which is well past what an average household produces in a single flush. The honest takeaway is that neither model will leave you disappointed on flush strength, so you should choose between them on the things that actually differ: water savings, cleaning, price and style. Both deliver the dependable single-flush clearing that has made TOTO a benchmark brand. For models that push to the 1,000-gram ceiling, see our roundup of the best 1,000-gram MaP toilets.

Which TOTO toilet is better for a bidet seat?

Bidet seats have become a major reason buyers choose TOTO specifically, since TOTO's WASHLET line is the most recognized in the category. Both of these toilets can take a bidet seat, but the Aquia IV is the one engineered around it. The WASHLET+ version of the Aquia IV is designed so that when you mount a matching TOTO WASHLET, the supply line and the power cord route discreetly behind the unit instead of dangling in view, giving you the clean, built-in look of an integrated smart toilet at a fraction of the cost. If you know a bidet seat is coming, buying the WASHLET+ Aquia IV from the start saves you a messier retrofit later.

The UltraMax II will accept a standard electric or non-electric bidet seat as well, since it uses a normal bowl mounting pattern, so you are not locked out of a bidet by choosing it. The difference is purely how tidy the finished installation looks, with the Aquia IV WASHLET+ hiding connections that remain visible on a standard UltraMax II install. If a bidet is not in your plans, this difference does not matter and you can weigh the two on price, water use and style instead. For a broader look at pairing toilets with bidet seats, our guide to the best bidet toilet seats covers compatibility and features.

How do height, comfort and dimensions compare?

Both toilets use TOTO's Universal Height, which puts the seat at roughly chair height (around 17 to 17.25 inches to the seat with the lid). Comfort-height bowls are easier to sit down on and stand up from, which is why they are the default recommendation for taller adults, older users and anyone with knee or hip concerns. Because both lines share this height, your choice between the UltraMax II and the Aquia IV does not force a trade on comfort, and both come in elongated bowls, the roomier and more popular shape for most bathrooms.

Both are designed for a standard 12-inch rough-in and use a normal supply connection. The clearest physical difference is the overall form. The UltraMax II's one-piece construction gives it a lower, continuous, modern profile with a tank that flows seamlessly into the bowl, which many buyers prefer visually and which fits compact or contemporary bathrooms well. The Aquia IV is a two-piece with a separate tank, so it has a slightly taller, more traditional tank line and the familiar two-piece silhouette. Both are skirted, so both hide the trapway for a clean side profile. If a low, sleek look is part of what you are buying, the UltraMax II delivers it; if you do not mind the standard two-piece form, the Aquia IV gives you the same Universal Height comfort for less.

How do the UltraMax II and Aquia IV fit the wider brand picture?

Neither of these is the only TOTO worth knowing, and neither is your only option in its price range. Within TOTO, the UltraMax II sits alongside the two-piece Drake and Drake II as a single-flush gravity option, while the Aquia IV anchors the dual-flush side of the catalog. If you are weighing TOTO's most popular two-piece against its one-piece flush engine, the TOTO Drake vs UltraMax II comparison covers that pairing directly and explains how the same flush philosophy plays out across body styles.

If you are open to looking beyond TOTO, the same money buys you strong Kohler and American Standard options. Our TOTO vs Kohler comparison weighs TOTO's Tornado and Double Cyclone flushes against Kohler's AquaPiston and Class Five systems, and the Kohler vs American Standard comparison covers those two brands if you want to widen the field further. On the power end, the American Standard Champion 4 vs Cadet 3 comparison shows how a maximum-power gravity toilet compares to a value model, a useful contrast if raw clog-clearing force is your top concern. The pattern across every brand is the same as it is here: decide which features you actually need, then pay for exactly that. Beyond these brands, Woodbridge, Swiss Madison and Gerber also make capable one-piece and dual-flush toilets worth a look if you want more options in the value tier.

Choose the TOTO UltraMax II if

The UltraMax II is the right pick when a clean one-piece look and effortless cleaning sit at the top of your list. Choose the UltraMax II if you want a seamless body with no tank-to-bowl seam to scrub, since its molded one-piece construction and fully skirted base make it the easiest of the two to wipe down. Choose it if you prefer the simplicity of a single flush lever, with nothing for a guest to get wrong and a fixed, dependable 1.28-gallon flush every time. Choose it for a primary or guest bathroom where a low, modern silhouette matters and you want TOTO's Double Cyclone flush and CeFiONtect glaze in the tidiest possible package. Accept in return a higher price than the two-piece Aquia IV and the loss of dual-flush water savings. The premium buys a cleaner look and the simplest operation TOTO offers.

Shop it here: check the current price on Amazon for the TOTO UltraMax II.

Choose the TOTO Aquia IV if

The Aquia IV is the right pick when water savings, value and bidet-readiness matter most. Choose the Aquia IV if you want the lowest real-world water use, since its dual-flush button drops to 0.8 gallons for liquid waste and settles near a 1.0-gallon effective average over a busy week. Choose it if you want TOTO quality at a friendlier two-piece price, with the same 800-gram flush and CeFiONtect glaze as the pricier one-piece. Choose it if a WASHLET bidet seat is in your plans, because the WASHLET+ design hides the supply and power connections for a clean, integrated upgrade later. Choose it for a remodel, a guest bath or a water-conscious household where flexibility and dollars-per-flush lead the decision. The Aquia IV gives most buyers more features for less money.

Shop it here: check the current price on Amazon for the TOTO Aquia IV.

Ready to shop? Check the current price on Amazon for the seamless one-piece TOTO UltraMax II or the dual-flush TOTO Aquia IV.