Can I Put an Elongated Toilet Seat on a Round Toilet?

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Paulk Webb


Freddie J. Hagopian

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can i put an elongated toilet seat on a round toilet

The elongated bowl takes up more space than the round one because it has two inches more on its length. Based on this fact, can I put an elongated toilet seat on a round toilet? You may be one of the many that ask themselves this question.

Fortunately, most toilets have a 12-inch rough-in, so it gives hope to this idea. If you want to put an elongated seat on a round bowl, you have to take time to get its measurement. You must get the exact product dimension. Since it’s a delicate process, you have to look at the details closely by reading this article.

Behind Elongated and Round Toilet Seats


In the United States, toilet seats are not universal as they are categorized as elongated and round. They can’t only be determined by shape but with measurements of round vs elongated toilet seats, which are the standard sizes.

Elongated toilet seats are 18.5 inches long and 14 inches wide, while the round ones are 16.5 inches long and 14 inches wide. As you can see, they differ in length. Due to the extra space on the elongated seat, many like it, especially men. This is the standard seat of toilets found in commercial and business areas like airports, hotels, and gas stations.

On the other hand, the round toilet seat is commonly seen in houses and homes. It will be your option if you have limited space in your bathroom or washroom. Moreover, it’s more compact than the elongated seat. You may also save a little money when buying the round seat as it’s smaller.

As introduced, elongated and round are the main standard sizes of toilet in the US. You should also know the parts that are linked to the measurement. First, the gap between the bolts that connect the toilet seat is measured regardless of the bowl shape.

This part is referred to as seat post holes and they are usually 5.5 inches away from each other. Secondly, you have to remember that the width of the toilet is the same despite the shape.

Thus, you can’t always say that a round toilet seat is too small for an elongated seat replacement. There may be chances that the width varies but it won’t be more than half an inch. Therefore, it’s just right to answer ‘yes’ to ‘Will elongated toilet seats fit the standard toilet?’.

Guide to Measuring the Toilet Seat


At this point, you know about standard sizes but it’s still crucial to take down measurements when planning to have a switch to an elongated seat for comfort. You have to check the length, width, and seat post holes.


It’s the most vital part to measure over the other two factors. If you don’t want to mess things up, you must be attentive to it. But still, you shouldn’t ignore width and seat post holes to ensure that you have the standard toilet seat to proceed with elongated seat replacement.

The measurement of the length starts between the seat holes up to the bowl’s end. To play it safe, you can do it until the bowl’s edge to avoid getting a shorter measurement.


As mentioned, the width is typically in a standard size of 14 inches. But there’s nothing wrong with measuring it for the sake of assurance. Check the widest part of the toilet part to get a concise measurement. Again, it’s best to do it edge to edge to not fall short on the digits.

Seat Post Holes

Another way to determine if your toilet is in a standard size is by measuring the space between the seat post holes. You only have to connect the holes to obtain the right numbers.

It’s convenient to do it when you remove the seat. But it’s fine if you don’t as long as you’re lining up your measuring tool in the center.

Putting an Elongated Toilet Seat on a Round Bowl

It’s a good thing that almost all toilets have 12-inch rough-in. Hence, it’s possible to put an elongated seat on a round toilet. You can still do it even when there’s a larger rough-in. However, plumbing configuration or moving the wall to give some more space to the toilet is required.

These procedures can be demanding but it’s all worth it if you wish for extra comfort. You’ll gain more benefits from doing so such as improvement of sanitary conditions because there will be less urine drip on the bowl.

You can check out great elongated toilet seats like BEMIS 1500EC 390 Lift-off Wood Elongated Toilet Seat, Kohler K-4636-0 Cachet Elongated White Toilet Seat, Mayfair 1847SLOW 000 Kendall Slow-Close Wood Toilet Seat, and TOTO Transitional SoftClose Elongated Seat.

Read more: Bemis vs Kohler toilet seat: which is better?


Can I put an elongated toilet seat on a round toilet? The answer to this question is in this article with a guide on how to take measurements properly. You may not completely replace your round toilet and just modify its seat for an elongated one for extra comfort and sanitary improvement.

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