If you’re deciding between the TOTO C5 and the TOTO S5, you’re looking at two of the most talked-about WASHLET bidet seats TOTO has ever made.
This comparison breaks down exactly how these two models differ so you can make the smartest choice for your bathroom.
| Feature | TOTO WASHLET C5 (SW3084) | TOTO WASHLET S5 (SW3446) |
|---|---|---|
| Image |  |
 |
| Dimensions (L x W x H) | 24″ x 17-9/16″ x 7-7/16″ | 24-3/8″ x 17-9/16″ x 7-7/16″ |
| Water Heating | Tank-type (limited warm water) | Instantaneous (endless warm water) |
| PREMIST | Yes | Yes |
| EWATER+ Wand Cleaning | Yes (wand only) | Yes (wand + CLEAN RESIN coating) |
| User Memory Settings | 2 users | 4 users |
| Night Light | No | Yes |
| Availability | Discontinued (2025) | Current model |
| Buy Now |  |
 |
1. TOTO WASHLET C5 Electronic Bidet Toilet Seat (SW3084#01)
The TOTO WASHLET C5 was a major step forward from the beloved C200, bringing EWATER+ wand self-cleaning into the mid-range TOTO lineup for the first time.
It’s a tank-type seat with a wireless remote, dual-action spray, and a slim SoftClose heated seat — everything you’d want in a reliable WASHLET at a mid-range price point.
Features
- PREMIST bowl misting before each use to help prevent waste adhesion
- EWATER+ self-cleaning wand (inside and out, before and after each use)
- Dual-action rear spray with oscillating and pulsating modes
- Front cleanse mode
- SoftClose heated seat with five temperature settings
- Warm air dryer with five temperature settings
- Built-in air deodorizer
- Wireless remote with illuminated touchpad and 2-user memory
- Tank-type water heater (warm water has a limited duration)
- Docking station for easy removal and cleaning
Pros
- Proven, reliable performance — millions of units sold
- More affordable than the S5, especially on clearance
- EWATER+ is a genuine hygiene upgrade over older C-series models
- Easy DIY installation with included hardware
Cons
- Discontinued in 2025 — no long-term manufacturer support guaranteed
- Tank-based water heating means warm water can run out during longer sessions
- Only 2 user memory slots
- No night light
If you can find the C5 at a significant discount, it’s still a very capable bidet seat — but you should go in knowing that TOTO has already moved on to the S5. For those wanting long-term peace of mind, it’s worth considering whether a discontinued model suits your needs. You can read more about how the C5 stacks up against older models in our TOTO C2 vs C5 comparison and our earlier look at the TOTO C5 vs C200 breakdown.
Check its current price on Amazon
2. TOTO WASHLET S5 Electronic Bidet Toilet Seat (SW3446#01)
The TOTO WASHLET S5 is TOTO’s current mid-range flagship, officially launched in 2025 as the direct successor to the C5.
It carries over everything that made the C5 popular — PREMIST, EWATER+, dual-action spray, heated seat, air dryer — while adding instantaneous water heating, a slimmer profile, a night light, four-user memory, and CLEAN RESIN wand coating.
Features
- Instantaneous (tankless) water heating for endless warm water
- PREMIST bowl misting before each use
- EWATER+ wand cleaning with CLEAN RESIN coating for enhanced hygiene
- Dual-action rear spray with oscillating and pulsating modes
- Front cleanse mode
- SoftClose heated seat with temperature control
- Warm air dryer with three variable temperature settings
- Automatic air deodorizer
- Night light illuminating the inside of the bowl
- Multifunction remote with 4-user memory
- Auto energy saver mode
- 19% slimmer profile than previous tank-type models
- Seamless seat design that eliminates dirt-collecting gaps
Pros
- Endless warm water — never runs out mid-use
- Slimmer, more modern design
- 4-user memory is ideal for households with multiple users
- Night light adds genuine convenience for nighttime use
- Current model — full manufacturer support and availability
- CLEAN RESIN wand coating is a meaningful hygiene upgrade
Cons
- Higher price than the discontinued C5
- Still a 1-year limited warranty (same as C5)
- No auto-open/close lid (that’s the S7A tier)
The S5 is a genuinely better product in almost every way. If you want the current generation of TOTO quality — with endless warm water and a slimmer build — this is where to put your money. It’s a strong pick whether you’re new to bidets or upgrading from an older seat. If you’re exploring what makes TOTO special, our guide on the best bidet brands gives helpful context, and you can also compare this tier to a premium option in our highest rated bidet toilet roundup.
Check its current price on Amazon
Water Heating: Tank vs. Tankless
This is the biggest functional difference between the C5 and the S5, and it matters more than you might think.
The C5 uses a tank-type water heater, which means it pre-heats a small reservoir of water.
That warm water supply is finite — in most cases, you get around 30–60 seconds of warm water before it starts cooling off.
The S5’s instantaneous water heater changes that completely.
It heats water on demand, so you get continuous warm water for as long as you need it — no time limit.
If longer cleansing sessions are important to you, or if multiple household members use the seat back-to-back, the S5 wins this category without question.
Winner: TOTO S5
Hygiene Technology: EWATER+ and CLEAN RESIN
Both seats feature PREMIST — a pre-use bowl misting that helps prevent waste from sticking — and EWATER+ wand self-cleaning using electrolyzed water.
But the S5 adds CLEAN RESIN, a specialized coating on both the wand and the seat that makes surfaces significantly harder for bacteria and residue to cling to.
It’s not just a cleaning feature — it’s a material upgrade that reduces how much cleaning is needed in the first place.
The C5’s EWATER+ is good, but the S5 takes hygiene a step further with CLEAN RESIN.
If you’re the kind of person who thinks carefully about bathroom hygiene — and frankly, that’s everyone reading a bidet comparison — this matters. Our bidet vs washlet guide explains why self-cleaning wand systems like EWATER+ are such a meaningful upgrade over standard bidet nozzles.
Winner: TOTO S5
Design and Comfort Features
Both seats share the same footprint at roughly 24″ x 17-9/16″ x 7-7/16″, so installation fit on standard elongated toilets is essentially identical.
Where they diverge is in polish.
The S5 is 19% slimmer in its tankless profile, giving it a cleaner, more modern look on the toilet.
It also adds a bowl night light, which the C5 completely lacks — a small feature that becomes surprisingly appreciated during nighttime bathroom trips.
Both seats use SoftClose lids and wireless remotes, but the S5 remote supports four-user memory versus the C5’s two, which is a practical upgrade for families.
The S5 also features a seamless seat design that eliminates the gap between seat and cover where dirt tends to collect on older bidet designs.
Winner: TOTO S5
Value for Money
The C5 was always praised for delivering a lot of TOTO quality at a reasonable price.
And if you can find one at a steep clearance discount, it’s still a functional, quality seat.
But the C5 is discontinued — TOTO transitioned fully to the S5 in 2025.
That means no new production, potentially limited parts availability down the road, and you’re buying a product at end-of-life.
The S5 costs more, but you’re buying the current generation with full manufacturer backing, better features, and a longer viable lifespan.
Unless the price difference is dramatic, the S5 is the better long-term value.
For additional context on what you should expect to spend on a quality bidet seat, our guide to best bidets for home use covers a wide range of budgets and options.
Winner: TOTO S5 (for long-term value)
Verdict — Which One Should You Buy?
The S5 is the better seat by nearly every measure — better water heating, more hygiene technology, a slimmer design, more user memory, and a night light.
It’s also the current model, which matters for long-term support.
That said, here’s how to think about it:
Buy the TOTO C5 if… you find it at a significant discount (think 40%+ off) and don’t mind owning a discontinued product. The core cleaning experience is still excellent, and if you’re a solo user with shorter sessions, the tank-based heating limitation won’t bother you much.
Buy the TOTO S5 if… you want the current generation TOTO quality with endless warm water, a slimmer profile, a night light, and support for four users. This is the right call for most households, and it’s what TOTO themselves recommend as the C5 replacement.
If you’re still exploring the broader TOTO lineup, our TOTO C5 vs C200 article shows how the C-series evolved, and our roundup of the best bidets for seniors shows why TOTO seats consistently top those lists too.
Frequently Asked Questions
Is the TOTO C5 discontinued?
Yes. TOTO officially transitioned from the C5 to the S5 in 2025. The C5 may still be available from some retailers while supplies last, but it is no longer in active production. The S5 is its direct replacement.
What is the main difference between the C5 and S5?
The most significant difference is water heating. The C5 uses a tank-based heater that provides warm water for a limited duration, while the S5 features instantaneous (tankless) heating for continuous warm water. The S5 also adds a night light, CLEAN RESIN wand coating, four-user memory, and a slimmer design.
Do both seats fit the same toilets?
Yes. Both the C5 and S5 are designed for standard elongated toilet bowls and share virtually identical footprints (approximately 24″ x 17-9/16″ x 7-7/16″). Neither is compatible with toilets that have a “French curve” design. If you’re unsure about fit, check our bidet toilet vs bidet seat guide for sizing tips.
Is the S5 worth the extra cost over the C5?
For most buyers, yes. The S5’s tankless heating alone is a meaningful upgrade that you’ll notice on every use. Add the cleaner design, better hygiene coating, night light, and four-user memory, and the S5 represents a significant improvement — not just a minor refresh. If you can find the C5 at a deep discount, it’s still decent, but the S5 is the smarter long-term purchase.
Conclusion
The TOTO C5 and S5 are more different than they might appear at first glance.
Both share the TOTO DNA — PREMIST, EWATER+, heated seat, warm air dryer — but the S5 improves on the C5 in every meaningful category: water heating, hygiene materials, design, and user capacity.
If you’re buying new today, the choice is clear: go with the TOTO S5.
It’s the current model, it’s better in nearly every way, and it’s the product TOTO wants you to own.
The C5 had a great run, but the S5 is where TOTO’s mid-range quality lives now.
Still comparing options? Check our full breakdown of the bidet toilet seat comparison chart to see how these TOTO models stack up against other top brands, or head to our best bidet brands guide if you’re still deciding whether TOTO is right for you.
