TOTO K300 vs. S550e: What’s the Difference?

The TOTO K300 and S550e may be among the greatest range of TOTO’s washlets, but they have noticeable differences and similarities.

If you’re finding it difficult to choose, this article can help.

I will compare these two products in this article. And I’ll also point out their features, major differences, similarities and lastly which seems to be the best buy.

Without any further ado, let’s check out our TOTO K300 vs. S550e washlet comparison.


TOTO K300 Washlet

The TOTO K300 washlet is the model after the C5 washlet. It’s the beginning model of TOTO’s luxury bidet. Check out the latest pricing here (Amazon Link).

It comes in two colors: the cotton white and the Sedona Beige, which some might refer to as light biscuit or off-white.

There are core features available in the TOTO K300 that many users seem to miss out on when buying this bidet. Below are the core features; please read through;


There are two different styles of the TOTO K300 washlet. The TOTO SW3036R#01 K300 and the TOTO SW3036#01 K300

The SW3036R#01 K300 has a self-cleaning nozzle and the TOTO eWater+ technology. In contrast, the SW3036#01 K300 features only a self-cleaning nozzle without the eWater+ features. 

Actually, there was no eWater+ function for K300 before, but the recent upgrade from the company included this feature. 

So the style with only the self-cleaning nozzle (SW3036#01 K300) is an old-style model. Meanwhile, the style with the self-cleaning nozzle and the TOTO eWater+ technology (SW3036R#01 K300) is an upgraded model.

Don’t get confused…

Feminine Feature

Aside from the eWater+ function, the new upgrade or SW3036R#01 K300 also features a basic feminine wash absent in the old model. In fact, the upgrade TOTO made in all their basic products recently was adding a basic feminine wash to them. 

It’s a marketing strategy to increase sales because many female bidet users always look out for bidets with a front wash. 

If you’re buying the TOTO K300, it’s best to go for the new upgraded model and not the old model. However, the price of the upgraded style is a few dollars higher.

Fitting for a Round Toilet

The new and upgraded models have no round version but only in an elongated design. 

However, the elongated design may fit a round toilet but won’t properly fit perfectly. It’s also likely to prove difficult when installing it in a French curved toilet. It will fit perfectly when you install it on a standard TOTO toilet.

If you have a French curve toilet, check out this article for the best bidet for it

PREMIST Feature 

Both the old model and the upgraded version have a PREMIST feature.

TOTO S550e Washlet

The TOTO S550e is the highest and last model of all TOTO washlet. It’s an advanced model of the S500e.

 It’s packed with all the luxurious features. So you should expect all the deluxe features that make a bidet seat eloquent. The durability of this product explains its popularity in the bidet market from its many users with good reviews.

It comes in two colors: cotton white and Sedona Beige (light Beige or light biscuit color).  


This high-tech luxury bidet seat comes in a slim design and can almost pass for the usual toilet seat. Its slim design maintains a bathroom aesthetic without looking off or bulky.

Fitting for a Round Toilet 

Still, on the design, one disadvantage of this bidet seat is that it only comes in an elongated version with no round version.

Not that it won’t fit a round toilet, it might (depending on the structure of your round toilet). However, one core issue is that it will create an extra overhang on the toilet. It makes it look unpleasant to the eye.

This bidet seat can fit into almost all TOTO toilets, including the one-piece ones.

If you intend to install it for a Kohler one-piece with deep curves, you might reconsider because it tends to fit the Kohler Rialto (Model K-4007-0) more. And that’s after you might have had lots of difficulties installing it, and it will also have an extra overhang.

I made a clear list of Kohler one-piece toilets and the bidets that will fit them here in this article. Kindly check it out if you’re purchasing a bidet for a Kohler one-piece toilet.

eWater+ and PREMIST Function 

As their highest washlet, of course, these two features are available. In fact, the company made it available in this model before extending it to other models, especially the eWater+.

Similarities Between the TOTO K300 vs. S550e

As the two top range bidet seats are from the same brand, the similarities between the TOTO K300 and the s550e are more than the differences.

Without wasting time going into detail, the primary features in both are a heated seat, soft close lid, dryer, deodorizer, air dryer, oscillating and pulsating wands, feminine wash, instant, continuous warm water, two user settings and PREMIST function.

Having specified that, it’s important to clarify that other core similarities between these bidets can also be seen on the TOTO K300 upgraded model (SW3036R#01) and the TOTO S550e. These similarities include;

eWater+ Auto-Cleans Wand

The TOTO S550e and the upgraded version K300 (SW3036R#01) have the eWater+ technology on their bidet nozzles. You won’t find this in the K300 old version.

This feature automatically sanitizes or cleans the nozzle before and after every use. This prevents the growth of bacteria in the wands.

Auto Wand eWater+ function on Remote

The S550e and the TOTO K300 upgraded model or style (SW3036R#01) have a one-push auto eWater+ button on their remote. However, you won’t find this feature in the old version of the TOTO K300.  

This feature on the remote makes it easier for you to clean the wand without constantly customizing it.

For a quick check, you can use the comparison table below to see their similarities, including the one I didn’t mention here. 

Difference Between the TOTO K300 vs. S550e

Whether with the new model of the TOTO K300 or the old model, the difference between the TOTO K300 and the S550e is very explicit. And, of course, the TOTO S550e beats the K300 to it.

The differences you will see in them are;

Auto-Open Soft and Close Lid

The soft-close lid feature is available in the TOTO K300 bidet (in old and new models). However, this does not happen automatically.

In the TOTO S550e bidet seat, the seat and lid automatically close and open when you want to use the toilet and after using it. You don’t need to touch it for this to happen.

Wide Front Wash

Both bidets have a feminine wash feature. However, the feminine wash in the TOTO S550e has a wider opening that makes the water rush out sturdier.

This feature is not available in any of the K300.

Led Night Light

Visiting the bathroom in the middle of the night with the TOTO K300 can be very tasking because it has no led night light that illuminates the toilet.

However, for the TOTO 550e, this feature is available. It’s the only TOTO bidet seat that has this feature.

TOTO K300 vs. S550e Remote Control

Both the TOTO K300 (both models) and the S550e bidet seat come with remote controls. The remote controls have only images on them without any written words; it’s still easy to comprehend. Also, you will notice a difference between the old model K300’s old remote and the new one.

Also read: Best Bidet With Remote Control

TOTO K300 Old Model Remote
TOTO K300 New Model Remote

TOTO S550e Remote Control

TOTO K300 vs. S550e: Price

As expected, there will always be a price difference between the K300 and the S550e because of their features. The price of the old model K300 is also different from the new model K300.

The price of S550e ranges above $1000:

While the price of K300 ranges above $500:

Installation Process of TOTO K300 vs. S550e

The installation process of both these bidet seats is super easy. Any able-bodied or slightly handy adult can easily set it up without a plumber.

Which One Should You Go For?

The TOTO S550e and K300 are both great bidet seats with great features. If you don’t want to miss out and want a luxurious bidet seat that has ALL the features, then the S550e should be your best buy.

However, if you care less about having all the features in the S550e, just stick with the K300. But remember, if you’re going for the K300, it’s best to get the new version and not the old one.

Summary Table Comparison

Features K300 S550e
Style Elongated Elongated
Model SW3036R#01 and SW3036#01 SW3056#01
Air Dryer Yes Yes
Deodorizer Yes Yes
‎‎Nightlight None Yes
Adjustable Water Pressure and Temperature Setting Yes Yes
Feminine Wash Yes Yes
Wide Front  None Yes
Warranty Manufacturer One Year Limited Manufacturer One Year Limited
Soft Close Lid Yes Yes
Auto Open and Close Lid None Yes
Warm Water Provision Yes Yes
Instant Warm Water Yes Yes
PREMIST Technology Yes Yes
eWater+ Technology (for toilet bowl) Yes Yes
Heated Seat Yes Yes
Self-cleaning Wand Yes Yes
eWater+ Self Clean Wand Yes for only SW3036R#01 model but None for SW3036#01 model Yes
External Wireless Remote Yes Yes
Auto Wand eWater+ function on Remote Yes for only SW3036R#01 model but None for SW3036#01 model Yes

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