TOTO C5 vs S550e: Every Feature Compared

Today, we’re comparing the TOTO C5 with the S550e. To start with, I owned and used the S550e for over a year before moving (mine was round and doesn’t fit the elongated toilet I’m using now). I haven’t owned the C5 long-term but I have installed and used it for reviewing purposes.

In short, I’d actually recommend the K300 Washlet over these two since it is close in price to the C5 while having 90% of the features of the S550e. The K300 can be found here and also here. If you’d like a full K300 review, see this article.

But in comparing the S550e and C5, the main differences include: 

• Type of water heater (limited vs endless warm water). 
• Self-cleaning PREMIST function. 
• User presets. 
• Slow-close vs auto-close seat/lid function. 
• Energy savings and Eco power-saving modes. 
• Seat height and curve. 
• Contemporary vs classic designs. 
• Auto flush compatibility. 

Quick note:

• Full TOTO C5 review w/Demos
• More options in the C5 price range (under $400), see this article

TOTO C5 vs S550e: Quick Summary Table 

Feature(s)	TOTO C5	TOTO S550e
Elongated vs Round	Elongated Only	Elongated Only
Water Heater Type	Basic Tank-Type Heater (~1min of Warm Water)	Instantaneous Heater (Endless Warm Water)
Warm Air Dryer w/Adjustable Temp	Y	Y
Heated Seat w/Adjustable Temp	Y	Y
Control	Wirless Remote w/Illuminated Touchpad	Wireless Remote w/Illuminated Touchpad
Air Deodorizer	Y	Y
Wand	Single Plastic Dual-Action Nozzle	Single Plastic Dual-Action Nozzle
Adjustable Nozzle	5 Positions	5 Positions
Wand Self-Clean Function	Automatic + On-Demand Self-Cleaning	Automatic + On-Demand Self-Cleaning
EWATER+ on Wand	Before/After Each Use	Before/After Each Use
Auto Toilet Bowl Cleaning	PREMIST of Bowl w/Water Before Each Use	EWATER+ Auto Cleanse Bow Before/After Each Use (Pre- and Post-Mist)
User Presets (Save Your Preferred Settings)	Water Pressure and Temperature, Nozzle Position	Water Pressure and Temperature, Nozzle Position
Easy Auto Function (One-Push Operation)	N	N
Bowl-Illuminating Night Light	N	Y
Adjustable Water Temperature and Pressure	Y	Y
Water Pressure (Flow Rate)	0.07-0.11 gal/min (or ~ 0.27-0.43 L/min)	0.08-0.11 gal/min (or ~0.29-0.43 L/min)
Oscillation Spray Setting (Back-and-Forth Spraying)	Y	Y
Massage-Pulse Spray Mode	Y	Y
Aerated Wash (Comfort and Efficiency)	Y	Y
Seat/Lid	Slow-Close (Slam-Free)	Auto Open/Close
Quick-Release Seat/Lid	Y	Y
Power-Saving Eco Mode(s)	3 Modes	4 Modes
Warranty	1-Year	1-Year
Curve	Rear Seat Height: 5.8″ (~14.7 cm)	Rear Seat Height: 5″ (~12.7 cm)
Design	Contemporary Only (SW3084)	Contemporary (SW3056) and Classic (SW3054)
Safety Seat Sensor	Y	Y
Auto Flush Compatibility	None	SW3054AT40#01 SW3056AT40#01

Features and Specs: TOTO S550e vs C5  

The TOTO C5 Washlet 

First up, is the TOTO C5 Washlet.

There are two versions of the C5, the SW3084 (Washlet) and SW3084T40 (Washlet+), the latter being for TOTO toilets only. So, make sure to get the right one.

You can compare prices for the C5 here (Amazon) and here (Bidet King). The least expensive option can be found here.

I recommend Bidet King since they have such great customer service which will probably be needed. TOTO’s customer service is pretty bad.

The C5 is an interesting bidet. It’s like a luxury bidet with a low-tech heater. It’s not often you find a tank-type heater alongside a self-disinfecting nozzle and automatic air deodorizer.  

IME, people often forego using the energy-saver settings. But using the Eco modes will be key if you want to save money on electrical costs with the C5. The seat takes around 15 minutes and the water ~10 minutes.  

So, without the automatic Eco mode activated, you’d have to turn the bidet seat/water heaters on 10-20min before each use of the toilet for max savings, which is impractical.  

Features and Specs of the TOTO C5 

Water Temperature: 

• Basic tank-type heater for ~1min of warm water. 
• 4 water temperature settings: “Off” (cold tap), from Low (95° F) to High (104° F)

Water Pressure: 

• Adjustable pressure w/5 settings. 
• Water flow rate between 0.07-0.11 gal (or 0.27 -0.43 L) per minute. 

Comfort, Convenience, and Design: 

• Convenient wireless remote with touchpad. 
• Warm air dryer: 3 temperature settings. 
• Heated seat: 3 temperature settings. 
• Automatic air deodorizer to keep the bathroom smelling fresh. 
• Aerated stream for added comfort. 
• With a seat height of 5.8” (14.7 cm), the C5 has a relatively continuous contour for a non-bulky appearance and plenty of room for sitting. 
• Low-profile design with minimal colors or visible decals.  

Seat and Lid: 

• Soft-close seat and lid to save wear and tear.  
• Quick-release tab and docking station for easy bidet removal and cleaning. 

Cleaning Wand and Spray Capability: 

• Single plastic dual-action nozzle for rear and frontal cleansing. 
• Nozzle adjustable to 5 positions for aiming accuracy. 
• Spray modes: Rear (regular), Rear Soft, and Front feminine. 
• Many users find the rear soft mode to be useful for soothing irritated skin (as with hemorrhoids, etc.). 
• Oscillating spray setting to have the wand moves back and forth for extra-thorough cleansing. 
• Massage/pulse mode for water pressure that pulses between strong and soft. 

Safety and Sanitation: 

• The nozzle automatically rinses before and after each use with EWATER+.  
• On-demand EWATER+ function for as-needed nozzle cleansing. 
• PREMIST function sprays the toilet with water before each use.  
• Safety sensor to prevent unwanted bidet activation. 

Water and Energy Efficiency: 

• Auto energy saver: automatically shift into low-power mode during periods of infrequent bidet use. 
• Timer energy saver: choose the hours you’d like the bidet to go into low-power mode. 
• Auto + Timer mode for max energy savings. 
• Aerated wash saves water long-term. 

The TOTO s550e Washlet 

The best bidet on the market is the TOTO S550e Washlet. You can compare prices here and here. Also, there is the open-box option which is the least expensive (found here) though availability varies.

It comes in Classic (SW3054) and Contemporary (SW3056). Both versions are available with and without Auto flush.  

If you have a TOTO toilet, get the SW3056AT40 or SW3054AT40, specifically, since they’re auto-flush compatible. If you don’t have a TOTO toilet, then get whichever is cheaper at the time of purchase. 

In the bidet community (yes, that’s a thing), the TOTO S550e is largely considered the best money can buy.  

It packs more technology in a slim flat seat than most bidets manage to fit in a bulky unit twice the size. Exaggerating a little, but not much.

You get a warm water supply that never runs out. Ten people can share the bidet back-to-back without having to worry about cold water. 

It cleans the toilet bowl and wand with a disinfecting solution (EWATER+) before AND after each use.   

The S550e is one of only two TOTO bidets that have a built-in nightlight. The light illuminates the toilet bowl and bathroom just enough so the user can navigate to and use the bidet, and remain in that semi-sleep state. 

With the S550e, you can open the toilet seat and lid with the wireless remote. Hands-free operation of the seat/lid is convenient, but enhances hygiene as well, since you don’t have to touch as many surfaces. 

Features and Specs of the TOTO S550e 

Water Temperature: 

• Instantaneous heating system for limitless warm water. 
• 4 temperature settings per wash mode: “Off” position (cold tap) and 3 levels that range from 86° F to the highest of 104° F. 

Water Pressure: 

• 5 water pressure settings to choose from. 
• Adjust the flow rate from 0.08 to 0.11 gal (or 0.32 – 0.43 L) per minute. 

Comfort, Convenience, and Design: 

• Wireless remote control with easy-to-read controls, illuminated touchpad, and magnetic wall-mounted cradle. 
• Warm air dryer with adjustable temperature.  
• Heated seat w/adjustable temperature range: “Off”, and from ~82 – 97 °F. 
• 2 User presets for saving preferred water temp and pressure, and nozzle position 
• Automatic air deodorizing system. 
• Auto flush compatibility with select models (SW3056AT40 and SW3054AT40). 
• Slim and compact design with a rear height of 5” (~12.7) with minimal visible decals, labels, etc. 

Seat and Lid: 

• Automatic opening/closing of seat and lid via remote control, for convenience and hygiene. Not even the S500e has this feature.  
• Quick-release tab on seat for easy bidet removal and cleaning. 

Cleaning Wand and Spray Capability: 

• Single, plastic dual-action nozzle for posterior and feminine hygiene.  
• Adjustable nozzle position (5 settings) for max aiming accuracy. 
• Multiple spray options: Rear, Rear Soft, Front, Wide Front 
• The Wide Front mode is for extra-soft feminine cleansing, and the Rear Soft setting can be used for soothing sensitive skin (e.g., hemorrhoids) and for bidet-style sitz bath sessions. 
• Standard oscillating spray mode for greater coverage and more effective cleansing. 
• Massage-pulse mode for a soothing massage effect. 

Safety and Sanitation: 

• The nozzle automatically self-cleans w/EWATER+ before and after each use. 
• An on-demand EWATER+ self-clean function for nozzle sanitation as needed. 
• Pre-mist AND post-mist function with EWATER+. The toilet is sprayed with EWATER+ before and after each use to help keep the bowl clean.  
• A built-in bowl-illuminating nightlight for safe bathroom navigation in the dark.  

Water and Energy Efficiency: 

• The most energy-efficient type of heater on the market uses power only when cleansing with warm water. 
• Auto Energy Saver (AES) and Auto Energy Saver+ (AES+): the toilet seat is set to low or turned off (respectively) during periods of infrequent bidet use. 
• Timer Energy Saver (TES): you choose which hours you want the bidet to go into low-power mode. 
• TES plus AES/AES+: combines all three Eco modes for max energy savings. 

Similarities and Differences 

The S550e Has an Advanced Water Heater 

Without a doubt, the main difference between the two bidets is the type of water heater. It may not sound like a big deal but it is.  

Luxury bidets like the S550e heat water instantaneously, so that the warm water never runs out.  

The TOTO C5 has a tank-type heater, which relies on a small reservoir of water that runs out after ~1 minute of cleansing.  

Interestingly, tank-type heaters are usually found on entry-level bidets like the TOTO A100 and Brondell S300. The C5 is thought of as more of a premium (mid-tier) option, yet it comes with a low-tech heater. 

Bidets in the C5 price range usually, at least, come with hybrid heaters (the kind that uses instantaneous and tank technology).  

Keep in mind, the ~1min of warm water you’ll get from the C5 is plenty for 99% of bowel movements.  

But endless warm water comes in handy in some situations, like when the bidet is used back-to-back, when cleansing the rear and frontal areas in the same session, or when performing a long sitz bath session. 

The TOTO C5 is About Half the Price 

If you’re on a budget, you’ll want to consider the C5 or even a less expensive option. The S550e is considered the best money can buy.  

You can get most of the benefits for much less, either by getting the C5 or another lower-tier bidet. Keep in mind, this is only true if you consider the price tag, since bidets like the C5 cost more to operate long-term.

This brings us to the next point.  

Energy Efficiency (Why the S550e Saves Money Long-Term) 

This is an important feature because it relates to the overall price of using a specific bidet. The TOTO C5 is less expensive upfront but costs more per month to operate.  

Bidets like the TOTO C5 that use a tank-type heater have to draw power 24/7 to keep the water ready for on-demand use.  

The C5 heater capacity is 225W, so the energy cost does add up over the month.  

The tankless heater of the S550e only uses power when needed, so if you use the bidet 5 times/day, it’s a few minutes max over the course of the day. 

Now, the TOTO C5 does have a few Eco modes that help reduce power consumption. Both bidets have this function. 

When activated, it memorizes when you’re least likely to use the bidet and turns the water and seat temperature down during low-use periods. More on this below. 

Bowl Auto-Clean Function 

Both bidets have the TOTO PREMIST feature. The toilet bowl is sprayed with water before each use, which keeps waste (read: poop) from sticking to the sides of the toilet.  

The S500 and S300 series bidets (including the S550e) spray the bowl before AND after each use (the post-mist function). Also, they spray with EWATER+, which is an electrolyte solution that sanitizes surfaces and further helps waste from sticking. 

The S550e Has a Wide Front Feminine Mode 

As you know by now, both bidets allow for rear and front feminine hygiene. But the TOTO S550e has a special soft feminine wash mode for extra-soft frontal cleansing.  

Softer pressure is best for frontal hygiene because over-spraying has been shown to dry out the vaginal mucosa which could potentially lead to infection (source).  

But to be clear, the lowest pressure setting on the TOTO C5 is plenty soft enough. Just use it in moderation per the bidet manual. 

The S550e Has an Auto Open/Close Function for Seat and Lid  

This feature allows you to open and close the toilet seat and lid via remote. It’s a pretty rare feature, IME.  I know Kohler has a luxury bidet with this feature, but that’s about it.  

Like most modern bidets, the TOTO C5 has slow-close hinges for slam-free closing of the bidet seat and lid.  

Seat Height and Curve (Comfort and Aesthetics) 

Generally, bidets with less of a curve are considered better-looking and more comfortable.  

For a tank-type bidet, the TOTO C5 is quite slim with a seat height of 5.8” (compare that to the TOTO A100 at over 7”).

But the S550e wins in this category..  

With a rear seat height of 5” (~12.7 cm), the TOTO S550e is among the slimmest, lowest-profile bidets on the market, second only to the S300e series bidets which are only 4” in the rear.

For reference, I’ve seen bidets as high as 7.4” (~17.8” cm) or more in the rear of the seat.

Not having a tank at the rear of the seat, creates a more streamlined, minimalistic, look and provides more room upfront.   

Contemporary vs Classic Designs 

The TOTO S550e is available in both classic and contemporary. This is hardly a selling point since the contemporary version looks much better by most standards and the C5 is available in this version.  

So, you know, TOTO bidets come styled in two ways, classic and contemporary.  

The classic version looks more like a bidet, while the contemporary version looks more like a high-end traditional toilet seat.

Again, it’s hardly worth mentioning but I want to be as thorough as possible. 

Some S550e Units Are Auto-Flush Compatible 

This won’t apply to most of you, but I know a few TOTO bidet users that have TOTO toilets. If you have a TOTO toilet with auto-flush technology, the S550e can be synced up with the toilet, to allow you to flush using the remote control. 

But, for auto-flush compatibility, you’ll have to make sure to get the right version of the bidet, the one with the “AT” in the SKU: SW3054AT40#01 or SW3056AT40#01.

Both Bidets Have These Features 

Self-Sanitizing Wand (via EWATER+) 

Video 

Most TOTO bidets use patented EWATER+ to clean the surfaces of the wand.  

EWATER+ is an electrolyte solution that forms sodium hypochlorite (NaClO).  

The solution keeps waste from sticking to the wand and helps sanitize the nozzle surface for an extra layer of protection. 

It’s similar to Brondell’s Silverando solution. The main difference is that, with TOTO, the wand is cleaned automatically before and after each use, while Brondell only has an on-demand wand sanitizing function. 

User Presets  

The C5 and S550e let 2 users save personal memory settings for preferred water pressure, water temp, and nozzle position.

Neither bidet has a one-push auto function—a feature that lets you get a generic wash/dry cycle with one push of a button.  

But they do have user presets, which is better. An auto function is like being able to order a #3 off of a menu, instead of specifying everything you want separately.  

User presets is having a waiter that memorizes your order.

Automatic Air Deodorizer 

This is a cool feature. The S550e and C5 bidets have an air deodorizer, as do most TOTO bidets (all but the A100, I believe). 

With other brands, it’s typically limited to luxury bidets.  

A small fan circulates air from the toilet bowl, through a carbon filter that breaks down molecules responsible for smelly odors. So, it removes embarrassing smells at the source, instead of just masking them as do air fresheners. 

Warm Air Dryer w/Adjustable Temp 

The TOTO C5 and S550e both come with a warm air dryer, a feature that’s pretty standard with all but the most basic of modern bidets. 

Most bidets at the $250+ price range will come with an air dryer. It’s worth every penny since having an air dryer helps the bidet pay for itself sooner.  

With a high-quality air dryer, you can ditch toilet paper altogether saving hundreds (even thousands over a lifetime of exclusive bidet use). 

It’s not absolutely necessary, since a dedicated bidet towel can be used in place of toilet paper. But the dryer remains one of the most popular bidet features for a reason. 

Slim Wireless Remote 

Both bidets come with a sleek wireless remote with an illuminated touchpad. The C5 remote is every bit as convenient and stylish as the S550e remote, just with fewer controls. 

Nozzle Oscillation Mode 

One of the most important features of an electric bidet is the nozzle oscillation function. It’s a setting that causes the nozzle to move back and forth for a better clean and wider coverage. 

Cleaning your butt with a stationary nozzle is like trying to wash your car while holding the hose in the same place.  

So, without this feature, the user has to shift and rock around to get water to the right places.  

Massage Spray Mode 

Of lesser importance is the massage mode. Massage-spray settings either have the nozzle oscillate rhythmically or pulse soft and strong water pressure.  

The pulse-massage version is more common, and that’s how the TOTO C5 and S550e operate: rotating strong and soft water pressure for a soothing massage-like effect. 

Energy Saver Modes 

As we touched on above, both bidets have energy-saver or “Eco” modes.  

The C5 Eco mode regulates both the water and seat temp.  

Since the S550e has a tankless heater, its Eco setting only has to regulate seat temperature. 

The power-saving modes include:  

• Auto Energy Saver: the bidet takes a few days to memorize periods of infrequent use and turns the water seat and/or water temp to low. 
• Auto Energy Saver +: With the S550e, the heated seat is shut off instead of set to low.  
• Timer Energy Saver: Choose a preset period of time (6 or 9 hours) to have the seat and/or water temp turned down.  
• Timer Energy Saver + Auto Energy Saver/Auto Energy Saver+: For max savings, you can use the auto Eco modes and choose a time period when you want the bidet in low-power mode.  

Aerated Spray (Comfort and Efficiency) 

Both bidets produce an aerated water stream. Microbubbles are incorporated into the outgoing water for a cleansing spray that’s both firmer and gentler.   

I’ve owned bidets with and without aerated cleansing and I can say that the water feels softer and firmer at the same time when it has microbubbles.  

Also, the air displaces some of the water, making the bidet more water-efficient.

Adjustable Everything (Water Pressure, Seat and Water Temp, Etc.) 

The wireless remotes that come with the C5 and S550e let you control everything from the temperature of the air dryer to the beeping sound of the remote.  

For example, you can adjust: 

• Water temperature and pressure. 
• Nozzle position (for aiming). 
• Various spray modes.  
• Deodorizer. 
• Flushing with certain S550e models. 
• Heated seat temperature. 

The list goes on. 

That should sum it up. Both are great options. If money isn’t a concern, go with the S550e, it’s a much better bidet overall.

If you can do without the tankless heater, I’d say go with the C5. For a full breakdown with images/vids, see the TOTO C5 Review.

Thanks for reading.