The TOTO WASHLET S7 and S5 sit at the top of TOTO’s bidet seat lineup — and deciding between them could transform how clean your bathroom stays every day.
You’re about to get a straight-shooting, feature-by-feature breakdown of both seats so you can pick the one that’s actually right for you.
| Feature | TOTO WASHLET S5 (SW3446) | TOTO WASHLET S7 (SW4726) |
|---|---|---|
| Image |  |
 |
| Dimensions (L x W x H) | 20.5″ x 14.8″ x 5.5″ | 20.9″ x 15.0″ x 4.1″ |
| Water Heating | Instantaneous (tankless) | Instantaneous (tankless) |
| EWATER+ Coverage | Wand only | Wand + toilet bowl |
| PREMIST | Yes | Yes |
| User Presets | 4 | 4 |
| Auto Flush Compatibility | No | Yes (kit sold separately) |
| Warranty | 1 year | 2 years |
| Buy Now |  |
 |
1. TOTO WASHLET S5 Electronic Bidet Toilet Seat (SW3446)
The TOTO WASHLET S5 is TOTO’s mid-range flagship — the direct replacement for the beloved C5 and the seat that Wirecutter named its top bidet pick.
It brings instantaneous warm water, a slimmer profile than its predecessor, and TOTO’s signature hygiene technology in a package that hits an exceptional sweet spot between performance and value.
If you’ve been eyeing the TOTO S7 vs C5 comparison or weighing other options on our bidet toilet seat comparison chart, the S5 is the seat that consistently comes out on top for most buyers.
Features
- Instantaneous tankless water heating — unlimited warm water with zero wait
- PREMIST technology pre-wets the bowl before each use to reduce waste adhesion
- EWATER+ electrolyzed water self-cleans the wand before and after each use
- Four user memory presets accessible from wireless remote
- Five spray modes including rear, rear soft, front, oscillating, and pulsating
- Heated SoftClose seat with five temperature levels
- Warm air dryer and built-in air deodorizer
- Auto-sensing LED nightlight
- CLEAN RESIN seat surface that repels dirt and grime
- Available in elongated and round; Cotton White and Sedona Beige
Pros
- Named 2025 Wirecutter Best Bidet Seat — independently verified performance
- 19% slimmer than the C5 it replaces — cleaner, more modern look
- Four user presets make it ideal for multi-person households
- Instantaneous heater means you never get hit with cold water mid-session
- PREMIST + EWATER+ together keep the bowl and wand noticeably cleaner
- Easy DIY installation in under 30 minutes — no plumber needed
Cons
- EWATER+ only cleans the wand — the bowl doesn’t get post-use EWATER+ misting
- No auto-flush compatibility
- 1-year warranty is shorter than the S7’s coverage
- No skin-contact seat sensor — uses pressure-based sensor that clicks on seating
The S5 is the seat for buyers who want every premium TOTO feature that actually matters day-to-day — without paying a premium for extras you might not use.
It belongs on anyone’s shortlist alongside the Brondell Swash 1400 and the other top-rated heated bidet toilet seats on the market.
Check its current price on Amazon
2. TOTO WASHLET S7 Electronic Bidet Toilet Seat (SW4726)
The TOTO WASHLET S7 is TOTO’s premium bidet seat — replacing the S500e and sitting just below the auto-open S7A in the lineup.
It builds on everything the S5 delivers and pushes further into luxury territory with a dramatically slimmer profile, expanded EWATER+ bowl cleaning, a skin-contact seat sensor, and compatibility with TOTO’s optional auto-flush kit.
If you’re designing a high-end bathroom upgrade and want a seat that genuinely rivals the look of an integrated smart toilet, the S7 is where the TOTO lineup gets serious.
Features
- Instantaneous tankless water heating — same as S5, no cold surprises
- EWATER+ coverage for both the wand AND the toilet bowl — post-use bowl misting included
- PREMIST bowl misting before each use
- Ultra-slim 4.1″ rear height — nearly 1.5 inches lower than the S5
- Skin-contact seat sensor (not pressure-based) — activates only when skin is detected
- Four user memory presets with wireless remote
- Five spray modes: rear, rear soft, front, oscillating, pulsating
- Wide-front cleaning mode for enhanced feminine wash
- Heated SoftClose seat, warm air dryer, power deodorizer, dual nightlights
- Auto-flush compatible with separately sold kit on select TOTO toilets
- WASHLET+ compatible — conceals power cord and water hose for integrated look
- 2-year limited warranty
Pros
- Full EWATER+ coverage — bowl stays cleaner between scrubs without any chemicals
- 4.1″ rear height is among the lowest profiles of any bidet seat available
- Skin sensor is smoother and more refined than pressure-based alternatives
- Auto-flush capability future-proofs the seat for TOTO WASHLET+ toilets
- Power deodorizer is noticeably more effective than the S5’s standard deodorizer
- 2-year warranty provides meaningful extra peace of mind at this price level
Cons
- Significantly higher price than the S5
- Auto-flush requires a compatible TOTO toilet and a separately purchased kit
- No auto open/close lid — that’s exclusive to the S7A
- WASHLET+ version (SW4726AT40) is designed for T20/T40 toilets — confirm compatibility
For buyers who want the most automated, self-maintaining bathroom experience without stepping all the way up to an integrated toilet, the S7 is the seat to get.
It pairs especially well with a TOTO WASHLET+ compatible toilet for that completely seamless, cord-free installation look.
Check its current price on Amazon
EWATER+ Coverage: The Biggest Real-World Difference
Both seats use EWATER+ — but they use it very differently, and this is the single most important distinction between the S5 and S7.
The S5 uses EWATER+ electrolyzed water to clean the wand before and after every use.
That’s excellent — the nozzle stays hygienic automatically, and you never need to manually clean it with chemicals.
The S7 does all of that, and then goes further.
After you leave the toilet, it mists the interior of the bowl with EWATER+ as well.
This passive, chemical-free bowl cleaning cycle happens automatically every time you use it — meaning the toilet bowl itself stays noticeably cleaner between your regular scrubs.
If you’ve ever been frustrated by how quickly a toilet bowl gets dingy, the S7’s bowl EWATER+ is a genuine quality-of-life upgrade that the S5 simply can’t match.
Winner: TOTO WASHLET S7 — full EWATER+ coverage on wand and bowl is a meaningful hygiene advantage.
Profile and Design: The S7 Looks Like a Different Seat
At 5.5 inches at its highest rear point, the S5 is already slimmer than the C5 it replaced — and it looks great on a modern toilet.
But the S7 sits at just 4.1 inches.
That 1.4-inch difference is more noticeable in person than it sounds on paper.
The S7 hugs the bowl and creates a profile that’s close to an integrated bidet toilet unit — especially when paired with a WASHLET+ compatible toilet where cords and hoses are fully concealed.
The S7 also features a seamless seat design with no visible gaps at the hinge, making it significantly easier to clean.
For buyers who are remodeling a bathroom or care deeply about the aesthetic, the S7’s design is a genuine differentiator.
You can see how both compare visually against other premium options in our bidet toilet seat comparison chart.
Winner: TOTO WASHLET S7 — a noticeably slimmer, more integrated look from every angle.
Seat Sensor and Controls: A Subtle but Real Upgrade
Both seats are controlled by a wireless remote with four user memory presets.
The control layout and spray options are nearly identical — you’re getting five spray modes, adjustable temperature and pressure, a dryer, a deodorizer, and a nightlight on both seats.
Where the S7 pulls ahead is the seat sensor.
The S5 uses a pressure-based sensor — you sit down, the seat compresses, a quiet click activates the seat’s functions.
It works perfectly well, but sensitive users notice the click.
The S7 uses a skin-contact sensor — it detects skin directly and activates only when someone is genuinely seated.
This makes the whole experience feel more seamless and eliminates the activation noise entirely.
It’s a subtle upgrade, but in a premium seat at this price point, the details matter.
Winner: TOTO WASHLET S7 — skin sensor is more refined and completely silent on seating.
Value and Warranty: The S5 Makes a Strong Case
The S5 comes in at a significantly lower price than the S7 while delivering most of the same day-to-day functionality.
You still get unlimited warm water, PREMIST, EWATER+ wand cleaning, four user presets, a nightlight, a dryer, and a deodorizer.
Wirecutter’s endorsement as best bidet seat isn’t a small thing — it means the S5 performed better in independent testing than virtually every other seat on the market at any price.
The S5’s 1-year warranty is shorter than the S7’s 2-year coverage, which is worth noting at this price tier.
But TOTO’s build quality across both seats is industry-leading — these seats are engineered to last well beyond the warranty period in normal household use.
For buyers who want luxury TOTO performance and have a tight budget ceiling, the S5 is genuinely one of the best bidets for existing toilets you can buy right now.
Winner: TOTO WASHLET S5 — significantly better value for buyers who don’t need full EWATER+ bowl coverage or auto-flush compatibility.
Verdict — Which One Should You Buy?
Both seats are exceptional — and you won’t be disappointed with either.
But they’re built for slightly different buyers, and understanding which camp you fall into makes the decision easy.
Buy the TOTO WASHLET S5 if:
- You want Wirecutter’s top-rated bidet seat at the most reasonable price
- EWATER+ wand cleaning is sufficient for your hygiene needs
- You don’t need auto-flush compatibility or plan to use the seat on a standard toilet
- You’re upgrading from a C5 or another tank-heater seat and want a clear performance jump
- You’re comparing it against other top-rated options like the Brondell Swash 1400
Buy the TOTO WASHLET S7 if:
- You want automatic bowl cleaning via EWATER+ — not just wand cleaning
- You’re pairing the seat with a TOTO WASHLET+ toilet for a fully integrated, cord-free look
- A 4.1″ profile that rivals an integrated unit matters to your bathroom design
- You want auto-flush capability now or as a future upgrade
- You want the 2-year warranty for added peace of mind
FAQ
Is the TOTO WASHLET S7 worth the price over the S5?
For most buyers, no — the S5 covers the core TOTO experience beautifully at a lower price, and Wirecutter agrees.
But if you want automatic bowl cleaning, a dramatically slimmer 4.1″ profile, or auto-flush compatibility for a WASHLET+ toilet setup, the S7’s upgrades are genuinely meaningful.
Browse our bidet comparisons archive if you want to explore more side-by-side breakdowns before deciding.
Do the TOTO S5 and S7 fit all toilets?
Both seats fit most standard elongated and round toilets and require a nearby GFCI outlet.
The SW4726AT40 version of the S7 is the WASHLET+ variant designed for T20/T40 TOTO toilets — it will also work on standard toilets but is optimized for concealed cord installation.
Always measure your toilet bowl before purchasing. If you need help finding the right fit, the bidet toilet seat comparison chart lists dimensions for every major model.
What is the difference between the S7 and S7A?
The S7 and S7A are otherwise identical — the only difference is that the S7A adds an automatic open and close lid with approach sensing.
If you want hands-free lid operation, the S7A is worth the step up.
If you’re happy operating the lid manually, the S7 gives you every other S7A feature at a lower cost.
Can I install either seat myself without a plumber?
Yes — both the S5 and S7 are designed for DIY installation.
You’ll need to attach the mounting plate to your toilet, connect a T-valve to the water supply line, and plug the seat into a nearby GFCI outlet.
Most installations take 15–30 minutes.
If you’re new to bidet seats, our guide on the best bidets for home use walks through what to expect from the setup process.
Conclusion
The TOTO WASHLET S5 and S7 are two of the finest bidet seats available today — both built to the same exacting TOTO standard, both delivering unlimited warm water, PREMIST bowl protection, and EWATER+ wand cleaning.
The S5 is the smarter buy for most people.
It’s Wirecutter-endorsed, independently tested, and covers every feature you’ll actually use every day.
The S7 is the right call when you want the complete hygiene package — automatic bowl misting, a 4.1″ ultra-slim profile, a refined skin sensor, and the option to add auto-flush down the line.
Either way, you’re stepping into the best of what TOTO engineering has to offer.
For more help finding your perfect seat, check out the bidet toilet seat comparison chart, our guide to the best heated bidet toilet seats, and the full bidets for existing toilets roundup.
Still on the fence? The Brondell Swash 1400 vs TOTO S5 and Brondell CL1700 vs TOTO S2 comparisons are also worth a read if you’re weighing non-TOTO alternatives before committing.
