TOTO WASHLET S5 Electronic Bidet Toilet Seat Review: Is It Worth the Upgrade?
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| TOTO WASHLET S5 Electronic Bidet Toilet Seat Review: Is It Worth the Upgrade? |
Personally Researched | Last Updated: August 2026 | Based on Clinical Studies & Personal Experience.
Bidet toilet seats have gone from a niche bathroom upgrade to one of the most popular home improvements in recent years, and TOTO's WASHLET line is widely considered the gold standard in the category.
The WASHLET S5↗ (model SW3446#01, elongated, Cotton White) is one of TOTO's mid-to-upper tier electronic bidet seats, combining instant water heating with a couple of standout hygiene features not commonly found at this price point.
This review breaks down what the S5 offers, how it performs, and who it's actually a good fit for.
Design and Build
The S5 is part of TOTO's redesigned S series, and it shows in the seat's slimmer, more streamlined profile compared to older WASHLET models.
Its seamless seat design removes the usual gap between the seat and lid where grime tends to collect, which makes wiping it down noticeably easier than older bidet seat designs.
At roughly 21 inches long, 15 inches wide, and about 5.5 inches at the rear, it sits a bit taller than a standard seat due to the internal components — something worth knowing if seat height matters to you.
Installation uses a quick-release docking station, so the seat lifts off easily for cleaning or maintenance without needing to detach hoses or wiring each time.
Key Features
Instantaneous water heating. Unlike tank-based bidet seats that can run out of warm water, the S5 heats water on demand, so the wash stream stays consistently warm for as long as you need it.
PREMIST. Before each use, the seat lightly mists the toilet bowl with water, which helps keep waste from sticking to the porcelain.
In practice, this tends to mean less frequent scrubbing and a cleaner bowl between cleanings.
EWATER+ wand cleaning. The spray wand is automatically rinsed with electrolyzed water before and after each use, which helps keep it sanitary without relying on harsh chemicals.
Comfort features. The S5 includes a heated seat with adjustable temperature, an adjustable warm air dryer, a built-in night light, and both front and rear wash modes with oscillating or pulsating spray options.
Wireless remote with memory presets. A slim wall-mounted remote controls wash mode, pressure, temperature, and seat position, with presets that can store settings for up to four users.
Performance
Everyday use is where the S5 stands out.
The instant heating system responds quickly, so there's no cold-water surprise at the start of a wash.
The PREMIST feature makes a real, visible difference in how much residue builds up in the bowl over time, and the EWATER+ system does a solid job keeping the wand itself free of buildup between uses.
The heated seat and warm air dryer add a noticeably more comfortable, spa-like experience, particularly in colder months.
The remote is generally easy to use, though as with many electronic bidets, there's a slight learning curve to finding your preferred pressure and position settings.
Where It Falls Short
The S5 isn't without drawbacks.
Some owners have found the memory function underwhelming, noting it doesn't fully save all personalized settings for each user despite being marketed as a multi-user preset system.
The seat height and forward slope created by the internal components has also been mentioned as noticeable by some users, and at this price point, it's worth deciding whether those features matter enough to justify the cost compared to simpler WASHLET models.
It also requires a nearby grounded (GFCI) electrical outlet and standard water line access, so installation isn't quite as simple as a basic non-electric bidet attachment.
It's a bigger project, though still manageable for most DIYers or a quick job for a plumber.
Who It's Best For
The WASHLET S5↗ makes the most sense for people who already know they want an electronic bidet seat and are looking for a step up from entry-level models — particularly if bowl cleanliness and wand hygiene are priorities.
It's a strong middle ground between TOTO's basic WASHLET seats and its flagship S7, offering most of the luxury experience without the top-tier price tag.
If you're new to bidets and just want to try the basics, a non-electric attachment is a cheaper way to start.
But if you're ready to commit to a full electronic seat, the S5's combination of PREMIST, EWATER+, and instant heating is hard to match at this level.
Frequently Asked Questions
1. Does the TOTO WASHLET S5 fit any toilet?
It's designed for elongated toilet bowls only (model SW3446#01). TOTO also sells a round-bowl version (SW3445#01), so measure your toilet before buying to confirm you get the right fit.
2. Does it require an electrical outlet?
Yes. The S5 needs a nearby grounded (GFCI) outlet for power, plus a standard water line connection.
It's not a plug-and-play install like a non-electric bidet attachment, so factor that into installation planning.
3. What is PREMIST and is it actually useful?
PREMIST automatically mists the toilet bowl with water right before use, which helps keep waste from sticking to the porcelain.
In everyday use, it noticeably reduces how often the bowl needs manual scrubbing.
4. How is EWATER+ different from a regular self-cleaning wand?
Instead of just rinsing with plain water, EWATER+ uses electrolyzed water to clean the wand before and after each use, offering a more thorough level of sanitation than a basic rinse.
5. Does the water actually stay warm the whole time?
Yes. The S5 uses instantaneous water heating rather than a limited-capacity tank, so the wash stream stays consistently warm no matter how long you use it.
6. Can multiple people in the same household use personalized settings?
The remote supports memory presets for up to four users, though some owners have noted the memory function doesn't always save every personalized setting as expected, so it's not perfectly reliable for a large household.
7. How difficult is installation?
It's more involved than a basic bidet attachment since it requires both a water line and an electrical outlet, but it uses a quick-release docking system that most DIYers can handle, or a plumber can install quickly if preferred.
8. Is the TOTO WASHLET S5 worth it compared to cheaper bidet seats?
If bowl cleanliness, wand hygiene, and consistent warm water matter to you, the S5's PREMIST and EWATER+ features offer real functional advantages over most seats in its price range.
If you just want basic bidet functionality, a simpler or non-electric model may be a better value.
TOTO WASHLET S5 Electronic Bidet Toilet Seat
Warm water wash & dry · Heated seat · Remote control operation
⭐ Trusted bathroom fixture brand · TOTO
As the full review covers, a warm-water wash is a genuinely gentler option than dry toilet paper for cleaning sensitive, irritated areas — something that matters a lot if hemorrhoids or fissures make regular wiping uncomfortable.
The adjustable water pressure and temperature let you dial in something comfortable rather than settling for a one-size-fits-all setting, and the warm air dry function means you're not left rubbing with paper afterward either.
It's a genuine quality-of-life upgrade, though as with any premium fixture, the price point means it's worth deciding how much that daily comfort is actually worth to you before buying.
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Conclusion
The TOTO WASHLET S5 delivers a genuinely upgraded bathroom experience, backed by real hygiene innovations rather than just added comfort features.
Its instant water heating, self-cleaning wand, and bowl-misting technology set it apart from most competitors in its price range, even if a few quirks — like the seat height and imperfect memory presets — keep it from being flawless.
For anyone serious about upgrading their toilet setup, it's one of the more well-rounded electronic bidet seats currently available.
