Choosing between the TOTO WASHLET S2 and KS6 is one of the most interesting decisions in the current TOTO lineup — they share the same core DNA but serve very different buyers.
You’re about to get a clear, honest breakdown of every meaningful difference so you can decide which one is right for your bathroom.
| Feature | TOTO WASHLET S2 (SW3346) | TOTO WASHLET KS6 (SW3946) |
|---|---|---|
| Image |  |
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| Dimensions (L x W x H) | 20.9″ x 15.4″ x 5.9″ | 25.3″ x 15.3″ x 11.8″ |
| Water Heating | Instantaneous (unlimited warm water) | Instantaneous (unlimited warm water) |
| Controls | Side-arm panel (attached) | Illuminated wireless remote (handheld/wall-mount) |
| Spray Settings | 3 modes + oscillating | 5 modes + oscillating + pulsating |
| Seat / Dryer Temp Settings | 3 / 3 | 5 / 5 |
| User Presets | None | 4 memory presets |
| Hygiene Tech | PREMIST + EWATER+ + CLEAN RESIN | PREMIST + EWATER+ + CLEAN RESIN |
| Buy Now |  |
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1. TOTO WASHLET S2 (SW3346)
The TOTO WASHLET S2 is the newest entry-level model in TOTO’s redesigned S series, directly replacing the discontinued C2.
It delivers instantaneous warm water, PREMIST bowl misting, and EWATER+ wand sanitization — all in a profile that is 19% slimmer than the older generation it replaced.
For buyers who want the full TOTO hygiene stack without paying for features they don’t need, the S2 is the most sensible starting point in the lineup.
Features
- Instantaneous tankless water heating — unlimited warm water with no lag
- PREMIST function wets the bowl before each use, reducing waste adhesion
- EWATER+ electrolyzed water automatically cleans the wand inside and out before and after every use
- CLEAN RESIN wand and seat surface resist bacterial buildup
- Three wash modes: rear, rear soft, and front, with oscillating spray option
- Heated SoftClose seat with three temperature settings
- Warm air dryer with three temperature settings
- Built-in air deodorizer and nightlight
- Side-arm control panel — always within reach, no batteries needed
- WASHLET+ compatible for concealed cord and hose installation
- Available in Cotton White and Sedona Beige; elongated and round sizes
Pros
- Every core TOTO hygiene feature — PREMIST, EWATER+, CLEAN RESIN — at the entry price
- Slimmer, lighter profile than the KS6, sits lower on the bowl
- Available in two colors and two bowl shapes for maximum toilet compatibility
- Side panel is reliable — nothing to lose, no batteries to replace
- One of the most affordable TOTO seats with instantaneous water heating
Cons
- No wireless remote — reaching the side panel can be awkward for some users
- Only three spray modes and three temperature settings (less granular adjustment)
- No user memory presets — each person must reset settings manually
- No pulsating spray mode
Check its current price on Amazon
2. TOTO WASHLET KS6 (SW3946)
The TOTO WASHLET KS6 is the successor to the well-regarded K300 and sits a meaningful step above the S2 in TOTO’s current lineup.
It carries the same foundational hygiene technology — instantaneous heating, PREMIST, EWATER+ — but layers on a wireless illuminated remote, five-level seat and dryer adjustment, pulsating spray, and four user memory presets for a noticeably more premium experience.
If you’re comparing this to the best heated bidet toilet seats on the market, the KS6 holds its own firmly in the luxury mid-range category.
Features
- Instantaneous tankless water heating — endless warm water from the first second
- Five spray settings including rear, rear soft, front, oscillating, and pulsating modes
- PREMIST bowl misting before each use to reduce waste buildup
- EWATER+ wand sanitization with electrolyzed water — cleans between every setting change
- CLEAN RESIN surfaces on the wand and seat
- Heated SoftClose seat with five temperature settings
- Warm air dryer with five temperature settings
- Illuminated wireless remote — handheld or wall-mountable
- Four user memory presets for personalized wash settings per household member
- Built-in air deodorizer and nightlight
- Sculpted low-profile silhouette designed for a seamless, elegant look
- WASHLET+ compatible; elongated size in Cotton White
Pros
- Wireless illuminated remote is more convenient for most users, especially those with limited mobility
- Five-level seat and dryer settings give significantly more personalization than the S2’s three
- Pulsating spray adds a therapeutic option the S2 doesn’t offer
- Four user presets make it ideal for multi-person households — no resetting every time
- EWATER+ cleans the wand between every single setting change, not just before and after use
- Elegant sculpted profile designed for visual cohesion with modern bathroom aesthetics
Cons
- Only available in Cotton White elongated — no round version, no Sedona Beige option
- Higher price point than the S2
- Remote requires batteries and can be misplaced
- Slightly bulkier rear height than the ultra-slim S2
Check its current price on Amazon
Head-to-Head: S2 vs KS6
Controls: Remote vs Side Panel
This is the single biggest practical difference between these two seats.
The S2 uses a side-arm panel that is always physically attached to the seat — you never lose it, you never need batteries, and you always know where it is.
The downside is that reaching sideways to operate it can feel awkward, particularly for elderly users or anyone with limited mobility.
If you’re shopping for someone with accessibility needs, the dedicated guide to the best bidets for seniors covers why remote-controlled seats like the KS6 are generally the easier choice.
The KS6’s illuminated wireless remote can be held in your hand or wall-mounted at chest height — which is simply more ergonomic for most users.
**Winner: TOTO WASHLET KS6** — the wireless remote is more practical for the majority of households.
Wash Settings and Personalization
Both seats deliver TOTO’s full hygiene suite: PREMIST, EWATER+, and CLEAN RESIN.
Where they diverge is in how much you can fine-tune the experience.
The S2 gives you three water temperature settings, three seat heat settings, three dryer settings, and three wash modes (plus oscillating) — which is enough for most users.
The KS6 steps up to five levels across every category, adds a pulsating massage spray, and gives you four saved user presets.
For a single-occupant bathroom, the S2’s settings are probably sufficient.
For a couple or family sharing the same toilet, the KS6’s four memory presets mean each person can dial in their own settings once and never touch them again — which is a real quality-of-life upgrade over time.
**Winner: TOTO WASHLET KS6** — more settings, pulsating spray, and user presets make it meaningfully more customizable.
Hygiene Technology
Both seats are equally matched here, and that deserves to be said plainly.
The S2 and KS6 both feature PREMIST (pre-use bowl misting), EWATER+ (electrolyzed water wand cleaning), and CLEAN RESIN (antimicrobial surface coating).
This is the same core hygiene stack you’ll find on TOTO’s higher-end S5 and S7 models — and it’s genuinely the best wand-cleaning system in the bidet seat category.
One subtle advantage goes to the KS6: its EWATER+ system cleans the wand between every setting change, not just before and after a full use cycle.
If you want to dig deeper into how this technology works, the bidet toilet seat comparison chart shows how TOTO’s hygiene systems compare across the full lineup.
**Winner: Tie** — both offer the full TOTO hygiene stack. The KS6 cleans between settings changes, but this is a minor distinction in daily use.
Design and Toilet Compatibility
The S2 wins here on pure flexibility.
It is available in elongated and round bowl sizes, and in both Cotton White and Sedona Beige — which makes it compatible with a wider range of existing toilets and bathroom color schemes.
If you’re weighing the color choices, the dedicated TOTO color guide is worth a read before deciding.
The KS6 comes only in Cotton White elongated.
If your toilet is round, or if your bathroom has a warmer beige palette, the S2 is automatically the more compatible choice.
**Winner: TOTO WASHLET S2** — available in more sizes and colors to match a wider range of bathrooms.
Value
The S2 costs noticeably less than the KS6, and for most buyers in a single-occupant bathroom, the S2 delivers genuinely outstanding value.
It has the same TOTO reliability, the same water heating, the same hygiene tech — just fewer bells and whistles.
The KS6’s premium is worth it when the wireless remote, extra personalization, and four user presets are features you’ll actually use.
If you’re comparing either of these to other bidets for existing toilets, both TOTO models are among the most hygiene-forward options at their respective price points.
**Winner: TOTO WASHLET S2** — better value for solo users or those who don’t need the extra customization.
Verdict: Which One Should You Buy?
**Buy the TOTO WASHLET S2 if…**
You want TOTO’s full hygiene package — PREMIST, EWATER+, CLEAN RESIN, and instantaneous warm water — at the most accessible price point.
You have a single-user bathroom and the side-arm panel is not an inconvenience for you.
You need a round bowl version, or you want Sedona Beige to match your existing fixtures.
You’re upgrading from an older tank-heater seat like the C2, and you want the most cost-efficient path to the current TOTO standard.
**Buy the TOTO WASHLET KS6 if…**
You want a wireless remote for easier, more natural control from a seated position.
Your household has multiple users who each want saved personal settings — the four presets eliminate the need to adjust anything each time.
You want the pulsating spray option and five-level adjustment on seat heat and dryer for a more spa-like experience.
Your bathroom has a modern, clean aesthetic and you want a seat with a sculpted, premium silhouette to match.
For a broader view of where these seats sit within the full TOTO ecosystem, the S2 comparison with the Brondell CL1700 is a useful read if you’re also considering non-TOTO options at the same price range.
FAQ
Q: Is the TOTO WASHLET KS6 the replacement for the K300?
Yes. The KS6 (SW3946) is the direct successor to the K300 in TOTO’s current lineup.
It retains the same wireless remote format and builds on it with an illuminated remote, PREMIST, and EWATER+ cleaning between setting changes.
If you were considering the K300, the KS6 is the current version to buy.
Q: Does the TOTO WASHLET S2 fit round toilets?
Yes. The S2 is available in both elongated (SW3346) and round (SW3345) bowl sizes.
The KS6, by contrast, is only available in elongated — so if you have a round toilet, the S2 is the only option between these two.
Q: What is the difference between EWATER+ on the S2 vs the KS6?
Both use EWATER+ electrolyzed water to sanitize the wand automatically.
The KS6 adds one additional cleaning trigger: the wand is cleaned between every setting change during use, not just at the start and end of a wash cycle.
In practical terms, both provide excellent wand hygiene — the KS6’s extra cleaning step is a refinement rather than a fundamental difference.
Q: Can I use either seat with a TOTO WASHLET+ compatible toilet?
Yes, both the S2 and the KS6 are WASHLET+ compatible, meaning they can be installed with select TOTO toilet models that conceal the power cord and water supply hose inside the toilet body.
This is relevant if you want a clean, wire-free installation aesthetic.
If you are building around a full TOTO ecosystem, the bidet toilet vs bidet seat guide can help you decide whether a WASHLET+ bundle or a standalone seat makes more sense for your bathroom.
Conclusion
Both the TOTO WASHLET S2 and KS6 are excellent seats from the world’s most trusted bidet manufacturer, and neither will disappoint you.
The S2 is the smarter buy for solo users who want TOTO’s hygiene tech at the most accessible price — and the flexibility of round and Sedona Beige options makes it the more universally compatible seat.
The KS6 is the upgrade worth paying for in shared bathrooms, where the wireless remote, four user presets, pulsating spray, and finer temperature control turn a good seat into a genuinely personalized experience.
If you’re still building out your overall bathroom upgrade, the bidet toilet seat comparison chart is the best next read — it shows how both of these seats compare to the full field, including the TOTO S5 and S7 if you’re considering stepping further up the lineup.
