One Piece vs Two Piece Toilet. Which Is Better?

One Piece vs Two Piece Toilet – A Comparison Review

One Piece vs Two Piece Toilet

One-Piece Good But Two-Piece Isn’t Necessarily Bad

When a one-piece and a two-piece toilet are placed side by side, which will you choose? Without getting into the cost and features, the one-piece is always the winner.

Why is that so?

Looks are everything. Yes, the one-piece toilet is better in appearance; it has a modern feel. That’s why.

But that is hardly the case for the pragmatic toilet hunters. Appearance may be the last thing on their list, they see beyond looks, sometimes even beyond cost. They see only benefits and value for their hard earn money.

So what are the benefits and value between the two?

It will depend on how you prioritize your needs and which one benefits you the most.

Both designs have their drawbacks even though they may have the same performance level. So understanding the pros and cons will help you decide on a toilet that’s right for your home and your budget.

In a hurry? You may skip straight to the summary.

Difference In Construction

Two Piece Toilet
TOTO Drake II Two Piece Toilet
It’s easy to differentiate between the two design with their construction.

The common two-piece toilet consists of a separate tank and bowl whereas the one-piece toilet will have the tank molded with the bowl as one whole unit.

You can tell the difference by looking at the joint between the tank and the bowl. A clear seam is visible on the two-piece toilet, and there’s none for the one-piece toilet.

What are the advantages and disadvantages of the two constructions?

The main advantage of the two-piece design is you can replace the tank and bowl separately. If the tank is broken, you will need to replace the tank, likewise for the bowl.

One Piece Toilet
KOHLER Santa Rosa One Piece Toilet
But if you broke either part of a one-piece toilet, you will need to replace the whole toilet. Perhaps, this is the only drawback of the one-piece toilet, besides cost.

And since the tank is fused with the bowl, there is no need to make provision to support the tank. That’s where some space can be saved and make the overall construction more compact, which explains why most of the space saver toilets are of the one-piece design.

However, for a siphonic toilet, there is a physical limit to the bowl length, unlike the washdown design.

Besides looking great, the one-piece toilet is very easy to clean and maintain. That’s the best advantage above all.

Keeping The Toilet Clean

The one-piece toilet is easier to clean because there is no gaps or joint between the toilet tank and the bowl. And its a lot more hygienic since there is no place for dirt and grime to gather. Most people choose one-piece design mainly for this reason.

The joint area of the two-piece toilet can be a breeding ground for mold and bacteria if left unclean over time. And it is difficult to clean the area thoroughly without removing the tank. Besides, there is the risk of leaks between the tank and bowl if the tank is not installed back properly.


Which performs better? One-piece or two-piece toilet.

Performance-wise, there is no difference between the one-piece and two-piece toilets.

They can have the same flushing power and efficiency. The interior parts are almost identical if they are from the same manufacturer. They may even have the same features and specifications.

So whether you prefer comfort height or water-saving feature or compact toilets, you can find in both one-piece and two-piece toilets.

Installation – One-Piece vs. Two-Piece Toilet

Installing a toilet
The one-piece toilet can be a challenge to install due to its size and weight. And it can be tricky when you have a small space. Strong arms and a good back will make an easy install; otherwise getting help is not an option.

But once you get the toilet into position, the installation is almost done. The rest of the work is easy, like connecting the water supply, mounting the seat, and caulking. So in this regard, the one-piece toilet is easy to install for the experienced DIYer.

The two-piece toilet is more comfortable to install in a sense you can deal with the tank and bowl separately. With lesser weight to wrestle with, typically one person can complete the entire installation.

However, the tricky part is mounting the fragile porcelain tank onto the bowl. Always follow the manufacturer’s instructions to a T to avoid leaks later. And cracks on either the bowl or the tank can happen when you overtighten the bolts.

Regardless if it’s a one-piece or two-piece toilet, get professional help if you aren’t confident with the work. And plumbing services usually will include hauling away your old crapper. So that is one less trouble versus if you were to do it yourself.


Since the one-piece toilet is one large piece of porcelain, there are no joining parts to upkeep. From an engineering point of view, the lesser parts or connectivity, the more reliable it will be.

Hence, upkeeping a one-piece toilet is super easy. There is no worry of water leaking out of the tank to mess up your bathroom floor.

The two-piece toilet will need the extra care for leaks once the rubber gasket that seal the tank has had its day.

Besides the usual replacement of tank interior parts, both designs can last for many years under proper care and usage. But since the one-piece model does not have the joining portion, the out-leaking problem does not exist. So it is a more durable toilet over the two-piece design.

The More Expensive One Piece Toilet

In general, a two-piece toilet cost less than its one-piece counterpart, for two reasons.

According to, about 80% of toilets sold are the two-piece toilet models. The main reason being they have been around longer, and homeowners are familiar with it. So that provides the economy of scale that relatively brings down the production cost.

While the one-piece toilet doesn’t quite have the market volume like the two-piece, its production cost is higher in comparison. The more complex production process of the one-piece toilet is also a factor.

But still, the one-piece design is affordable for most consumers. The price ranges from $300 up to over $1000 for some higher-end models.


One-piece or two-piece toilet. Have you decided which one is more suitable for you?

Let’s recap what has been discussed.

One-Piece Toilet


  • Great aesthetics. Good match for a contemporary bathroom design in every modern home.
  • Easy to clean and up keep. More hygienic with no joining parts for dirt and bacteria to hide.
  • No worry of water leaking out of the tank and flooding the floor.
  • More durable due to no joining part to maintain.
  • More compact in size. A space saving toilet for small bathrooms.


  • Cannot replace toilet tank or bowl separately. Once you break any part of the porcelain, you need a new replacement for the whole toilet.
  • Heavy and bulky to install. But when secured to the toilet flange, the job is 90% done. So in this regard, it may also deem as an advantage to some people.
  • Higher price.
Two-Piece Toilet


  • The tank and bowl can be installed separately, so it is less bulky and lighter to handle.
  • The toilet tank and bowl can be replaced individually.
  • Lower cost.


  • Need to clean the area where the tank joins to the bowl. And it’s difficult to thoroughly clean the joining area without removing the tank.
  • Joining area attracts dirt, grime and bacteria.
  • Water will leak out of the tank when the rubber seal starts to deteriorate.
  • Not as sleek looking as the one-piece model.

So there you have it, the differences between the one-piece and two-piece toilet. If you have a point or 2 to add, feel free to leave your comments below. Thanks for reading & happy shopping!

Woodbridgebath T-0019 One Piece Toilet


  1. Hi, is it true that the 2 piece will flush better given that the tank is higher?

    • Hi.

      A higher tank with a relatively higher water level will add power to the flush, regardless of the toilet being one or two-piece.

  2. I liked that you said that one reason to buy a one-piece toilet is that it requires less maintenance. I have been thinking about getting a new toilet but I have been worried about the cost of repairs that I would have to make. I will be sure to consider this option now that I understand that it will be durable and last a long time without the need for major repair.

    • Hi Ashley. The parts that need repair or replacement are those inside the tank, just like the two-piece. Generally, these parts are not expensive to replace. Other than that there isn’t much to maintain besides cleaning. But do be careful not to break any part of the body though.

  3. How easy is it to find parts for one piece toilets (seats, flapper, fill valve)? How hard are they to replace?

    • Hi Dale.

      Most one piece are using similar parts as the two piece toilets. But there maybe some slight variation on the mounting, so always check to make sure you are buying the correct parts for your toilet. How easy to find will depend on the brand/model, like do they have a parts inventory to support or are they using 3rd party parts….etc They can be replaced just like any two piece toilets in most cases.

      I’d be more concern if they have the parts you mentioned available. So I’d check that before deciding to buy.

  4. what happens if the seat breaks? Can you replace the seat on a one piece or do you have to replace the whole toilet

    • Hi Lisa.

      The seat is a separate accessory you can replace any time. As long as the porcelain body of the toilet is not broken you are good.

    • yes you can replace the seat on a one piece toilet………

  5. We already replaced a two piece toilet with Kohler’s Santa Rosa model and love it. We went this route because of the ‘banjo’ that extends from the bathroom sink. Now the master bath is on the agenda. The toilet stands alone and yet for the $100 price difference, between Kohler’s Cimmarron and Santa Rosa, it’s a tough decision indeed. Yet I think because we already have SR and love it, we will likely get the same again. And Bud, like how the article was written and especially the summary! Helps make the decision easier!

    • Thanks Julie.

      (Your link was removed because it goes to a 404)

  6. It was quite nice how you said that there was no difference between the one-piece and two-piece toilet when it comes to performance, flushing power, and efficiency. The reason why I liked it is that of the fact that I don’t want to be torn between the two types. We just need to get the old toilet replaced with a new one because we’re nearly done remodeling the bathroom and the look of the old toilet will not fit the aesthetic of the place. Thanks. I’ll talk to my parents about this.

  7. I want to replace my older 2 piece toilet with a 1 piece. How do I measure it to be sure it covers the same floor space? I’m concerned that the vinyl flooring will not look good if it isn’t covered the same.

    • Hi Sharon thanks for dropping by.

      This can be tricky if your concern is the traces of the old toilet is not well covered. But first you got to take measurement of the existing toilet base or footprint; mainly the length and the width (widest part). And please take note of where the widest part is, it could be the front, in the middle or towards the end. Then start shopping for a new toilet with a base bigger than your existing toilet.

      And not forgetting the rough-in size of the new toilet has to match the old one.

      Depending on which one piece toilet you are looking at and you might need to ask for more details from the manufacturer. Not all will show the dimension of the toilet base. I think only Kohler shows the footprint measurement.

      If you need help, just hit the Contact link right below and give me more detail about your existing toilet. I’ll try my best to find a match for you.


  8. Thank you very much for writing this. I did not know the difference and I am buying a new toilet and the salesman is selling me a one piece and a friend told me two pieces is better because you have to replace the whole toilet if it leaks on a one piece. But I see that the two pieces is more likely to leak. The one piece fits what I want to do.

    • Hi Sandy, thanks for the kind words.

      The leaking on a one piece is usually due to an aging gasket which can be replaced easily. Unless you cracked or broke any part of the porcelain that causes the leak then you will have to replace the whole toilet. So be exceptionally careful when you are installing it.


  9. Now I know I have to buy a one piece toilet for a higher price. Thanks for the great advice.

  10. Very concise and helpful. I am replacing a two piece with a one piece and was having second thoughts. Thanks for the great information.

  11. Excellent article. ..very well organized & logically written…thanks.

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