TOTO WASHLET S5 Electronic Bidet Toilet Seat review (2026)
- Instantaneous tankless water heating — warm water never runs out mid-wash
- EWATER+ electrolyzed water auto-cleans the wand before and after every use
- PREMIST automatically mists the bowl before each use to reduce waste adhesion
- Wireless wall-mountable remote with 4 personalized user memory profiles
- Heated SoftClose seat (82–97°F) with warm air dryer (95–140°F, 3 settings)
- Built-in air deodorizer activates automatically during use
- CLEAN RESIN antimicrobial seat coating resists biofilm buildup
- Model SW3446#01 (elongated) | SW3445#01 (round) | 1-year limited warranty
The TOTO WASHLET S5 is the 2025–2026 replacement for TOTO's long-running C5, and it fixes the two complaints that followed the C5 everywhere: the tank-based water heater that went cold after 30–45 seconds, and the side-panel controls that required memorizing button combinations. The S5 switches to an instantaneous ceramic heater for continuous warm water and adds a wireless remote with four saved user profiles. Those are the right upgrades, and they move this seat to a meaningfully different tier of daily comfort.
At a street price of roughly $680–$780, the S5 sits in the middle of TOTO's current lineup — above the S2 (which trades the wireless remote and user profiles for a $200 savings) and well below the S7 and S7A (which add bowl-level EWATER+ cleaning, a slimmer profile, a longer warranty, and — in the S7A only — auto open/close lid). For most households, the S5 is where the value equation tips in TOTO's favor: you get the core luxury features that actually affect daily use without paying the $600–$700 premium to step up to the S7.
This review synthesizes published manufacturer specifications, independent retailer and expert assessments, and patterns from verified owner feedback across Amazon and retail platforms. We do not claim hands-on lab testing. We will flag known limitations honestly, because at $700 a buyer deserves a clear picture of what they are and are not getting.
Features & performance
Instantaneous Tankless Water Heating
This is the headline upgrade over the C5 and every budget bidet seat on the market. Instead of a reservoir that stores a small volume of pre-heated water and runs cold after 30–60 seconds, the S5 uses a ceramic instantaneous heater that warms water on demand — continuously, for as long as you need. Water temperature is adjustable in the 95–104°F range. Owners consistently name this feature as the single biggest quality-of-life improvement. The tradeoff is higher peak power draw (up to 1,426W during active use), but TOTO's own testing shows 38% lower standby energy consumption versus tank-type predecessors.
EWATER+ Wand Self-Cleaning
After every use, the spray wand is automatically misted with EWATER+, TOTO's electrolyzed water technology. Electrolyzing tap water produces a mild hypochlorous acid solution — safe for skin and surfaces, but effective at inhibiting bacterial growth on the wand. The wand also extends and retracts so it is covered when not in use. One important caveat: on the S5, EWATER+ applies to the wand only. The S7 and S7A extend this treatment to the bowl surface and seat as well. If bowl-level sanitation is a priority, that is an honest reason to consider stepping up.
PREMIST Bowl Pre-Wetting
Before you sit down, a sensor detects your approach and automatically mists the inside of the bowl with EWATER+. Wet ceramic surfaces resist waste adhesion significantly better than dry ones. The result is a bowl that needs less scrubbing between cleanings. This feature works in the background — you never have to activate it manually. Owners rarely call it out by name, but it contributes to the consistent feedback that the toilet simply stays cleaner.
Wireless Remote with 4-User Memory Profiles
The remote mounts to the wall and controls every function: rear wash, front wash (bidet), oscillating and pulsating spray modes, water temperature, water pressure, wand position, dryer temperature, and the deodorizer. It stores personalized settings for up to four users, so each person in a household can call up their preferences with one press. This is a real upgrade over the C5's side-panel controls and over budget seats where you re-set preferences every use. One complaint that surfaces occasionally: some users find the remote interface slightly less intuitive than expected during the initial learning curve.
Heated Seat and Warm Air Dryer
The SoftClose seat heats to a range of 82–97°F with five selectable temperature levels. The warm air dryer operates between 95–140°F across three temperature settings. The dryer does work, but it is not fast — a complete hands-free dry typically takes 2–4 minutes. Owners who want to stay fully hands-free appreciate it; others keep a small amount of toilet paper on hand for finishing. Three dryer temperature settings is also fewer than the S7 and S7A, which offer five. This is a real, if minor, tradeoff at this price point.
CLEAN RESIN Antimicrobial Seat Coating
The seat surface uses TOTO's CLEAN RESIN material, which incorporates antimicrobial agents directly into the resin at the molecular level. This resists the biofilm and staining that accumulates on standard plastic toilet seats over time. The seamless underside design — one of the visible changes from the C5's seamed seat — also eliminates the gap where grime traditionally collects. Owners who have switched from standard seats consistently note that the S5 stays looking cleaner with less effort.
Night Light and Automatic Deodorizer
A soft LED night light illuminates the bowl — useful for middle-of-the-night trips without full bathroom lights. One reviewer notes the S5's nightlight is actually brighter and more practical than the side-panel light on the S7, which is an interesting edge-case win for the lower-tier seat. The automatic deodorizer activates when you sit down and filters air through a carbon filter. It is not marketed as a whole-room deodorizer; it addresses bowl-level odor at the source.
Installation and Compatibility
The S5 replaces your existing toilet seat using standard mounting hardware included in the box. Installation takes most people 20–40 minutes with basic tools — remove the old seat, install the mounting bracket, snap the WASHLET on, connect the T-valve to the water supply, and plug in. The critical requirement is a GFCI-protected electrical outlet within approximately 4 feet of the toilet. The power cord is 3.9 feet. If your bathroom lacks a nearby GFCI outlet — which is common in older construction — you will need an electrician to install one, adding $100–$250 to the total cost. This is the most commonly cited barrier in owner feedback.
Pros
- Endless warm water is a genuine upgrade — no cold cutoff mid-wash, which is the top complaint about every tank-based bidet seat
- EWATER+ wand cleaning runs automatically every time, requiring no maintenance habit from the owner
- PREMIST keeps the bowl noticeably cleaner between cleanings
- Wireless remote with 4-user memory profiles is practical for multi-person households
- Seamless seat design with CLEAN RESIN coating is easier to keep clean than standard seats
- 19% slimmer profile than the C5 fits more toilet configurations and looks less bulky
- 38% reduction in standby energy vs. prior generation despite higher peak draw
- Fits elongated and round toilets (separate model numbers)
Cons
- EWATER+ covers the wand only — no bowl or seat surface treatment (that requires stepping up to the S7 or S7A)
- Warm air dryer is slow — expect 2–4 minutes for a hands-free dry; most owners keep minimal toilet paper on hand
- Only 3 dryer temperature settings vs. 5 on the S7 and S7A
- No auto open/close lid or auto-flush — those features are exclusive to the S7A
- Pressure sensor for seat occupancy detection produces an audible click that bothers some owners; S7A uses a touch sensor instead
- 1-year warranty is short for a $700+ product; the S7 and S7A carry 2-year coverage
- Requires a GFCI outlet within 4 feet of the toilet — a genuine installation barrier in older bathrooms that may add electrician cost
- A small number of owners have reported water line connection issues; monitor the T-valve connection after installation
What owners say
Owners praise
- The switch from tank heating to instant heating is consistently called out as the biggest practical improvement — owners who upgraded from C5 or budget seats describe the consistent warm water as 'transformative'
- The PREMIST and EWATER+ combination is repeatedly credited for keeping the toilet visibly cleaner with no additional effort from the user
- The wireless remote and 4-user memory profiles get strong praise in households with multiple users — no re-setting preferences each visit
- Build quality and material feel are frequently described as solid and professional-grade, clearly a step above budget bidet seats in the $150–$300 range
- Owners who had to install an outlet note that once that barrier was cleared, installation itself was straightforward and the result was worth the effort
Common complaints
- The GFCI outlet requirement catches buyers off guard — owners in older homes or apartments frequently discover they need an electrician before the unit can even be plugged in
- The warm air dryer is functional but slow; owners expecting to go fully paper-free often end up using a small amount of toilet paper to finish drying and save time
- The audible click from the pressure-based seat occupancy sensor annoys a subset of owners, particularly in quiet bathrooms at night
- A minority of owners have reported recurring moisture or seepage at the water line connection point; checking and re-tightening the T-valve fitting after the first week is worth the effort
- Some buyers feel the 1-year warranty is insufficient at this price tier, especially compared to Brondell's 3-year coverage on comparable-priced seats
Who it's for
Buy it if: ">Homeowners who want to replace a standard toilet seat with a genuine upgrade — continuous warm water, self-cleaning wand, PREMIST, and a wireless remote with user memory — and have a GFCI outlet already in place or are willing to have one installed. Strong fit for multi-person households (4 user profiles), anyone who has been frustrated by a tank-based bidet seat running cold, and buyers who want TOTO quality without the $1,300–$1,400 jump to the S7."
Skip it if: Renters who cannot modify bathroom electrical; buyers without a GFCI outlet who are not prepared to pay an electrician; anyone whose top priority is auto-open lid or bowl-level EWATER+ (requires S7A); budget buyers — the TOTO S2 at ~$490 covers the core wash features for less
Alternatives to consider
- TOTO WASHLET S2 (SW3224#01). Same instantaneous water heating and EWATER+ wand cleaning as the S5, about $190 less — the right choice if you can live without the wireless remote, 4-user memory profiles, and night light
- Brondell Swash 1400. Costs roughly $150 less than the S5, comes with a 3-year warranty (vs. TOTO's 1-year), and has more wash modes — the top alternative if warranty length or price is a sticking point; build quality is a half-step behind TOTO
- TOTO WASHLET S7 (SW4726#01). About $600 more than the S5 but adds EWATER+ bowl-level cleaning, a power deodorizer, 5-setting dryer, slimmer profile, touch sensor (no clicking), and a 2-year warranty — justified if bowl sanitation and premium design matter to you
Our verdict
Frequently asked questions
Does the TOTO Washlet S5 fit my toilet?
The S5 comes in two versions: SW3446 for elongated bowls and SW3445 for round bowls. Verify your bowl shape before ordering — the product page on Amazon (ASIN B0FCTH1NSS) is the elongated version. Most standard two-piece and one-piece toilets are compatible, but TOTO also publishes a full compatibility list on their website. The unit requires a GFCI electrical outlet within approximately 4 feet of the toilet; this is the more common installation barrier.
How is the S5 different from the old C5?
The three biggest differences: (1) The S5 uses an instantaneous ceramic heater for continuous warm water — the C5's tank heater ran cold after 30–45 seconds. (2) The S5 includes a wireless wall-mountable remote with 4-user memory profiles — the C5 used a side-panel control. (3) The S5's seat uses CLEAN RESIN antimicrobial coating and a seamless underside design that is easier to clean. Both models include PREMIST and EWATER+ wand cleaning.
Does the S5 have an auto-open lid?
No. Auto open/close lid functionality is exclusive to the TOTO WASHLET S7A at the top of the current lineup. The S5 lid opens and closes manually. If auto-open is a must-have, you will need to budget for the S7A, which runs roughly $1,400.
What electrical outlet do I need, and what if I do not have one near the toilet?
The S5 requires a standard 120V GFCI-protected outlet within approximately 4 feet of the toilet (the power cord is 3.9 feet). GFCI outlets are required by code in bathrooms in most US states, but many older homes have a single outlet on the vanity wall — not near the toilet. If you do not have a conveniently located GFCI outlet, a licensed electrician can typically add one in 1–2 hours. Budget $100–$250 for that work depending on your location.
Is the TOTO Washlet S5 energy-efficient?
The peak draw during active wash and dry is 1,271–1,426 watts — comparable to a hair dryer, but only for the 1–2 minutes per use. In standby mode, the S5 uses far less power than the older tank-type C5; TOTO's testing shows 38% lower standby energy consumption. An energy-saver mode further reduces idle power draw during periods of low use. Monthly energy cost for most households is modest — typically a few dollars added to the electricity bill.
Why does the S5 cost more than the Brondell Swash 1400, and is TOTO worth the premium?
The Brondell Swash 1400 costs roughly $150 less and includes a 3-year warranty versus TOTO's 1-year — those are real advantages. TOTO charges a premium for its proprietary EWATER+ electrolyzed water system, PREMIST bowl pre-wetting, CLEAN RESIN antimicrobial coating, and the build quality consistency of a manufacturer that has produced bidet seats since 1980. Independent reviewers consistently rate TOTO's seat hardware, nozzle mechanics, and long-term reliability above Brondell's. If budget and warranty length are your primary criteria, Brondell is a legitimate alternative. If you want the most refined daily experience and trust the brand's track record, the S5 premium is defensible.