How to Measure for a Toilet Seat

woman lifting toilet seat lid

There are lots of reasons to buy a new toilet seat. Maybe your existing seat is broken or looking tired. Maybe you simply fancy updating your bathroom or ensuite. Either way, you’ll want a replacement that’s the right size for your loo. In the guide below, we’ll explain how to measure for a toilet seat. Read on to find out:

broken toilet seat lid

How long do loo seats last?

Loo seats are used daily, so they experience a lot of wear and tear. They tend to last about five years depending on how much they are used, what they are made from and how well they are made.

What is a standard size toilet seat?

It would be fantastic if all seats came in a standard size. Unfortunately, toilet seat sizes do vary. That’s why it's crucial to have accurate toilet seat dimensions before searching for a seat that fits.

white modern toilet with round seat

How do you measure for a new toilet seat?

To find the right size seat for your toilet pan, you will need to take three or four measurements:

  • The width of the pan at the widest point
  • The length of the pan from the fixing holes to the edge of the pan
  • The distance between the fixing holes – the standard distance is 155cm, but it's worth making sure this is the case

You may also need…

  • The distance between the fixing holes and the wall or cistern

For standard toilets, the first three measurements will probably be enough. However, certain types of seats, such as raised seats, require space between the fixing holes and the cistern or wall. That’s where the fourth measurement may come in handy.

What shape should I buy?

Take care to match the shape of your seat to the shape of your toilet pan. There are several styles available, including round, square and D-shaped toilet seats. If you choose the wrong shape – such as a square toilet seat for a round pan – the seat won't fit correctly.

What if I use a seat that isn’t the right size?

If you use a seat that isn’t the correct size for your toilet, you may face issues with its appearance or usability. At best, your loo may look a bit odd due to having an oversized or undersized seat. It might also be less comfortable than a loo with a correctly sized seat. At worst, the seat will fit so poorly that it may be awkward or unsafe to use, especially for children or people with mobility issues. You might not even be able to attach the seat at all.

We use our loos regularly, so it’s well worth investing in a seat that fits properly.

white modern toilet with square seat

Want more advice?

Once you have your measurements, you can be confident about finding a seat that fits your pan. All that’s left is to decide on a style, budget and any additional features, such as soft close hinges. Use our handy toilet seat guide to choose the best toilet seat for you. To ensure a successful fitting, check out our article on how to replace a toilet seat.

Shop the collection

Plumbworld offer a wide selection of loo seats in different colours, shapes, sizes, and materials. We also stock well-known brands including Roca, Bemis and Croydex. Shop the collection today and find the perfect option for your bathroom.

If you're looking for further information on toilet seats and toilets, take a look at the following posts - Are Toilet Seats a Standard Size? - Toilet Seat Buying Guide - How to Replace a Toilet Seat.


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