TOTO Aimes vs Aquia IV: One Clear Winner for Your Home!

Choosing between the TOTO Aimes and the TOTO Aquia IV is one of the most common toilet dilemmas you’ll face when upgrading your bathroom.

Both are sleek, one-piece WASHLET+ ready toilets — but they serve different needs, and picking the wrong one could leave you wishing you’d gone the other way.

Feature	TOTO Aimes (MS626234CEFG)	TOTO Aquia IV (MS646234CEMFGN)
Image
Dimensions (L x W x H)	28-7/16″ x 17-5/16″ x 27-15/16″	28-1/2″ x 17-5/8″ x 28-1/8″
Flush System	TORNADO FLUSH®	DYNAMAX TORNADO FLUSH®
Flush Volume	1.28 GPF (single flush)	Dual flush: 1.28 GPF / 0.9 GPF
Flush Activation	Left-hand chrome trip lever	Chrome push-button (top of tank)
Surface Protection	CEFIONTECT® ceramic glaze	CEFIONTECT® ceramic glaze
Design Style	Bold, high-profile tank; skirted	Sleek, low-profile tank; skirted
WASHLET+ Ready	Yes (T40 compatible)	Yes (T40 compatible)
Buy Now

1. TOTO Aimes One-Piece Elongated 1.28 GPF Toilet (MS626234CEFG)

The TOTO Aimes is a bold, eye-catching one-piece toilet built around a high-profile tank that commands attention in any bathroom.

It uses TOTO’s TORNADO FLUSH system — a hole-free rim with dual nozzles that creates a powerful centrifugal cleaning action — paired with CEFIONTECT ceramic glaze to keep the bowl looking clean between scrubs.

Features

One-piece skirted design with high-profile tank — bold and modern aesthetic
TORNADO FLUSH® with hole-free rim and dual nozzles for efficient bowl cleaning
CEFIONTECT® ceramic glaze prevents waste and debris from sticking
Universal Height for comfortable seated and standing transitions
WASHLET+ ready (T40 compatible) — power cord and water line concealed in bowl channel
Left-hand chrome trip lever flush activation
12″ rough-in (10″ and 14″ adapters available separately)
ADA compliant, EPA WaterSense certified

Pros

Striking high-profile design that stands out as a bathroom focal point
TORNADO FLUSH delivers a powerful, thorough clean every time
CEFIONTECT glaze dramatically reduces how often you need to scrub the bowl
Concealed trapway is easy to wipe clean — no awkward nooks to reach around
One-piece construction eliminates the gap between tank and bowl where bacteria hides
WASHLET+ compatibility lets you add a bidet seat with hidden wiring

Cons

Single-flush only at 1.28 GPF — no water-saving 0.9 GPF option for liquid waste
High-profile tank may not suit minimalist or contemporary-style bathrooms
Trip lever flush is more traditional — no hands-free push-button option

The Aimes is the toilet for buyers who want their bathroom fixture to make a statement.

If you’ve been browsing our best toilets with bidet roundup and want a foundation that pairs beautifully with a TOTO WASHLET seat, the Aimes is one of the most visually striking options in the lineup.

Check its current price on Amazon

2. TOTO Aquia IV One-Piece Dual Flush 1.28/0.9 GPF Toilet (MS646234CEMFGN)

The TOTO Aquia IV is TOTO’s most water-efficient one-piece toilet — a sleek, low-profile design that quietly does everything right without calling attention to itself.

Its DYNAMAX TORNADO FLUSH delivers a full 360-degree cleaning sweep using 100% of the flush water, and the dual-flush push-button system puts real water conservation in your hands every time you flush.

Features

One-piece fully skirted design — sleek and understated, suits modern bathrooms
DYNAMAX TORNADO FLUSH® — 360° cleaning power reaches every part of the bowl
Dual flush: 1.28 GPF (full flush) and 0.9 GPF (light rinse)
Chrome push-button on top of tank — center-mounted for intuitive use
CEFIONTECT® ceramic glaze keeps bowl clean with less effort
Universal Height for comfort across a wide range of users
WASHLET+ ready (T40 compatible) with concealed cord and supply line channel
12″ rough-in (10″ and 14″ adapters available separately)
EPA WaterSense certified; meets CALGreen requirements

Pros

Dual flush is a genuine water saver — 0.9 GPF for liquid waste adds up to real savings
DYNAMAX TORNADO FLUSH is the more powerful, 360° evolution of the standard TORNADO FLUSH
Low-profile tank blends cleanly into contemporary and modern bathroom aesthetics
Push-button flush is intuitive and feels more refined than a trip lever
Fully skirted design with smooth base is effortless to clean
WASHLET+ compatibility for a clean, cord-free TOTO bidet seat pairing

Cons

Lower-profile tank is less visually bold — not the right pick if you want a statement piece
Dual-flush system takes a moment to learn (short press vs long press)

If water savings matter to you and you prefer a contemporary, understated design, the Aquia IV is the smarter long-term purchase.

It shows up as a top pick in our TOTO Drake vs Nexus vs Aquia IV comparison, where it consistently wins on water efficiency and modern aesthetics — and it pairs brilliantly with any seat you’d find in our bidet toilet seat comparison chart.

Check its current price on Amazon

Design and Aesthetics: Which Toilet Looks Better in Your Bathroom?

The Aimes and the Aquia IV represent two different design philosophies — and the right pick depends entirely on the vibe of your bathroom.

The Aimes has a high-profile tank that sits tall and imposing behind the bowl, giving it a bold, sculptural presence.

It’s the kind of toilet that guests notice — a deliberate design statement that elevates the whole room.

The Aquia IV takes the opposite approach.

Its low-profile tank sits closer to the bowl and keeps everything sleek and horizontal, which suits contemporary or minimalist bathrooms far better.

If your bathroom has clean lines, floating vanities, and a modern tile scheme, the Aquia IV’s silhouette will feel more intentional.

Both have a fully skirted design that conceals the trapway and creates a smooth, seamless exterior — making both much easier to clean than a traditional exposed-trapway toilet.

For a deeper look at how skirted design compares across TOTO’s full lineup, see our TOTO AP vs EP wall-hung toilet comparison, which covers the same skirted design philosophy in TOTO’s wall-mount range.

Winner: Aimes for bold drama. Aquia IV for clean minimalism.

Flushing Performance: TORNADO FLUSH vs DYNAMAX TORNADO FLUSH

Both toilets use TOTO’s signature dual-nozzle, hole-free rim flushing technology — but there’s a meaningful difference between them.

The Aimes uses TORNADO FLUSH, which sends water through two powerful nozzles to create a centrifugal rinsing action that cleans the entire bowl without a rim channel.

The Aquia IV uses DYNAMAX TORNADO FLUSH — an evolution of the same system, but with a redesigned inner bowl that reduces turbulence and achieves a full 360-degree cleaning sweep.

The result is a quieter, more efficient flush that reaches every corner of the bowl with less water.

In real-world use, both are impressive and clog-free performers — but the Aquia IV’s DYNAMAX system is technically the more advanced flush.

If you want context on how TOTO’s flush technology stacks up against other brands, our best toilets with bidet guide covers the full range.

Winner: Aquia IV — DYNAMAX TORNADO FLUSH is the newer, more refined system.

Water Efficiency: Single Flush vs Dual Flush

This is where the Aquia IV wins clearly and decisively.

The Aimes flushes at a fixed 1.28 GPF every time — there’s no option to use less water for lighter loads.

The Aquia IV gives you a choice: 1.28 GPF for solid waste and 0.9 GPF for liquid waste.

That 0.4 GPF difference per light flush might sound minor, but across an average household flushing multiple times a day, it adds up to hundreds of gallons saved every year.

Both toilets are EPA WaterSense certified at their full flush volume, so neither is wasteful — but if water conservation is a priority, the Aquia IV gives you a meaningful tool the Aimes simply doesn’t have.

You can read more about the long-term water savings of efficient toilets in our bidet toilet vs bidet seat guide.

Winner: Aquia IV — dual flush is a genuine advantage for households watching their water bill.

WASHLET+ Compatibility and Bidet Pairing

Both the Aimes and Aquia IV are WASHLET+ ready at the T40 level, which means you can add any TOTO WASHLET+ compatible bidet seat and have the power cord and water supply line completely hidden inside the toilet bowl channel.

There are no visible hoses and no cable management headaches — the toilet and seat look like a single integrated unit.

Both work with the full range of TOTO WASHLET+ seats, from the entry-level S2 all the way up to the flagship S7A with auto-open lid.

If you’re pairing either toilet with a WASHLET seat, check out our TOTO C5 vs S7 washlet comparison to find the right seat for your needs, or browse the bidet toilet seat comparison chart for a broader look at what’s available.

For the cleanest installation on either toilet, the TOTO WASHLET S7 or S7A is the obvious partner — you get bowl EWATER+ misting that keeps the toilet clean between uses, which pairs naturally with the CEFIONTECT glaze on both the Aimes and Aquia IV.

Winner: Tie — both are equally WASHLET+ capable.

Installation and Fit: What You Need to Know Before You Buy

Both toilets are one-piece elongated models designed for a standard 12-inch rough-in.

Both can be adapted for 10″ or 14″ rough-ins with separately sold TOTO adapter kits, so odd rough-in measurements aren’t a dealbreaker for either.

In terms of footprint, they’re nearly identical — the Aimes measures 28-7/16″ × 17-5/16″ and the Aquia IV comes in at approximately 28-1/2″ × 17-5/8″, so both will fit in the same bathroom layouts.

The main difference is height — the Aimes stands at 27-15/16″ while the Aquia IV is slightly taller at around 28-1/8″, but that’s negligible and primarily affects how the toilet looks against the wall, not whether it fits.

Both are Universal Height models, designed to meet ADA standards for comfortable seated position across most users.

If you’re also weighing the option of adding a bidet seat to your existing toilet rather than replacing the whole fixture, our best bidets for existing toilets guide is worth a read first.

Winner: Tie — near-identical footprint makes both equally easy to install in most bathrooms.

Verdict: Which One Should You Buy?

Both the TOTO Aimes and TOTO Aquia IV are excellent one-piece toilets built to the same high TOTO standard — CEFIONTECT glaze, WASHLET+ readiness, and Universal Height comfort come standard on both.

But they’re built for different buyers.

Buy the TOTO Aimes if… you want a visually bold toilet that makes a design statement, you prefer a traditional trip lever flush, and water savings from dual flushing aren’t a priority for your household.

It’s the right pick for bathrooms where the toilet is meant to be noticed — a classic, sculptural piece that happens to flush superbly.

Buy the TOTO Aquia IV if… you want the more advanced DYNAMAX TORNADO FLUSH, genuine water savings through dual flushing, a sleeker and more modern silhouette, and the most future-proof toilet in this price range.

For most buyers upgrading their bathroom in a contemporary home, the Aquia IV is the smarter purchase — it costs similar, flushes better by the numbers, and saves real water over time.

If you’re still deciding which TOTO ecosystem to build around, our highest-rated bidet toilet guide and our overview of the best bidet brands can help you see the full picture.

Frequently Asked Questions

Is the TOTO Aimes being discontinued?

As of now, the TOTO Aimes (MS626234CEFG) remains an active product in TOTO’s lineup and is not discontinued.

It’s part of TOTO’s Aimes collection alongside lavatories, faucets, and tubs, and continues to be available through authorized retailers.

Can I use a non-TOTO bidet seat with the Aimes or Aquia IV?

Yes — both toilets accept standard elongated bidet seats from any brand for a universal connection.

However, for the WASHLET+ concealed-cord installation (no visible hoses), you must use a TOTO WASHLET+ compatible seat (T40 designation).

Non-TOTO seats will still work perfectly, they’ll just have an external water supply hose running from the seat to the toilet’s shutoff valve.

What’s the difference between TORNADO FLUSH and DYNAMAX TORNADO FLUSH?

TORNADO FLUSH (used in the Aimes) uses two nozzles to create a centrifugal cleaning action that rinses most of the bowl efficiently.

DYNAMAX TORNADO FLUSH (used in the Aquia IV) is the evolved version — it achieves a true 360-degree sweep using the full momentum of the flush water, with a redesigned bowl shape that reduces turbulence and noise.

The DYNAMAX version is generally considered the more powerful and thorough cleaner of the two.

Which toilet is better for a household trying to reduce water usage?

The Aquia IV wins this clearly.

Its dual-flush system lets you choose 0.9 GPF for liquid waste and 1.28 GPF for solid waste — a real, measurable water savings over using 1.28 GPF every single flush as the Aimes does.

For a household of three to four people, switching to a dual-flush toilet can save several thousand gallons of water annually.

Conclusion

Both the TOTO Aimes and TOTO Aquia IV are genuinely great toilets — and you won’t be disappointed by either one.

But the better buy for most people is the Aquia IV.

You get a more advanced flush system, meaningful water savings from dual flushing, a cleaner contemporary profile, and the same WASHLET+ readiness and CEFIONTECT protection as the Aimes.

The Aimes wins on drama and bold design — if that’s what your bathroom calls for, it’s the right choice.

But if you’re building a smart, efficient, modern bathroom that can grow into a full TOTO WASHLET+ setup, the Aquia IV is the foundation worth investing in.

For your next step, check out our bidet toilet seat comparison chart to find the perfect WASHLET to pair with whichever toilet you choose — or head to our best toilets with bidet guide if you’re still weighing full integrated smart toilet options.