Bidet Water Filters: Everything You Need To Know

By Veronica Fletcher | 
Last updated on June 29, 2021

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A bidet can be a serious investment. It’s only natural to want to prolong its lifespan and ensure it works flawlessly for many years to come.

That’s one of the reasons people choose to invest in a bidet water filter. Depending on the quality of your water supply, you may find it a good idea to invest in a filter for your bidet seat.

In this article, I help to clear up some of the confusion around bidet water filters, including:

Ready? Let’s jump right in.

What is a bidet water filter?

Bidet filters sit in-between your t-adapter and the bidet hose

Over time, mineral deposits and small sedimentary particles from your water supply can build up inside your bidet seat and clog the nozzles.

Bidet filters work to remove all of these particles from your water supply before they reach your bidet. 

They also help to reduce hard water deposits from building up in the seat. Some will remove chlorine.

The most advanced filters will even help to sterilize the water. 

Bidet filters are cheap and easy to install. They’re an inline feature, meaning you place them in between the t-adapter and the bidet hose. 

Electric and non-electric bidets can both benefit from an external filter.

Do I need a bidet water filter?

Bidets don’t need a water filter to work. But if you live in an area with hard water, or you have a natural unfiltered water supply, they’re recommended. They’re a preventative measure to help prolong the life of your bidet – sort of like a phone case.

What happens if you don’t use a bidet water filter? Over time, small particles in your water stream can damage the bidet or cause the nozzles to clog.

A quick scan of multiple bidet warranty terms and conditions highlights that they don’t cover damage due to small particles in your water – so it’s up to you to stop that from happening. The best way to do this is with a water filter.

Toto, Bio Bidet, Smart Bidet, Brondell, and Alpha Bidets all state that their warranties don’t cover:

damage or loss resulting from sediments or foreign matter contained in a water system‘.

Wording typically found in bidet warranty terms

Toto goes a step further and also includes ‘damage or loss resulting from the quality of water in the region where the product is used‘.

If you live in a city with a municipal water supply, filters aren’t super important because the water will already be pretty clean.

Also, if you already have a whole house filtration system, there’s usually no need to fit a separate bidet filter.

But if you live somewhere with:

  • old pipes
  • a natural water supply (e.g. a well)*
  • an area with known hard water

You’re much more likely to see sediment build up under these circumstances.

*Assuming you don’t already have a house filtration system.

Brand-specific information relating to external bidet filters

Different bidet brands offer different advice around the use of external filters. Toto and Bio Bidet in particular have unique issues surrounding bidet filters.

Using an external water filter with a Toto washlet

A toto quick connect t-adapter vs a standard bidet t-adapter

Toto washlets aren’t compatible with the bidet filters available to customers in North America.

Toto washlets use quick-connect fittings while the filters require standard thread fittings, so unless you come up with a DIY solution you won’t be able to connect a bidet filter to your washlet.

They don’t mention the need for an external bidet filter anywhere in their manuals or on their website.

If you know you have very hard water, it may be worth looking into other solutions such as a whole house filtration system.

Using an external water filter with a Bio Bidet bidet

Bio Bidet state in their user manual that you can only use ‘Bio Bidet Carbon & Iodine water filters‘ with their products. If you choose to install a different brand or type of external filter you will void your warranty.

They only recommend using a filter in areas with known hard water issues. However, this is only a recommendation, and using one in a different area won’t affect your warranty.

If you install one, they state that it must be replaced every 3 months.

The bidets don’t ship with an inline filter, so you’ll need to purchase one separately if you want one.

Other brands

Brondell state:

Customers with hard water, well water, and softened water can extend the life of their bidet seat by purchasing and installing an external inline water filter to be used with the Swash. The bidet filter should be changed every six months.

Brondell do sell their own brand of external bidet filters, so I would recommend getting one of those, but I couldn’t find anything to suggest you couldn’t use a different brand if you wanted to. The bidets don’t ship with an inline filter, so you need to purchase one separately.

The advice from Alpha bidet, Smart bidet and Kohler is similar. They don’t say you need a filter, but they offer one as an accessory you can buy alongside your bidet.

How long do bidet water filters last?

A clean bidet filter vs a dirty one

Bidet filters last an average of 6 months, but this ranges between 4-8 months. The harder your water and the more small particles there are, the less time the filter will last.

As the filter starts to fill up, you might notice the water pressure in your bidet drop. This is indicative that something is obstructing the water flow to your bidet, and an old external filet is a likely culprit.

What are the different kinds of bidet water filters?

There are a few different bidet water filters on the market.

The main goal of the filters is to:

  • Remove any solid particulates
  • Soften the water and stop it from causing limescale
  • Remove chlorine which can dry out skin

Each individual filter will do one or a mixture of these things.

There are three main types of water filter.

Sediment water filter

A sediment water filter removes unwanted sediment from your water stream by using a mesh material to trap it. The mesh block will stop any sand, rust, dust and other solid impurities from reaching your bidet.

A sediment only filter won’t treat the water in any way, remove chlorine, or protect against calcification from hard water.

Sediment filters are best for users who don’t suffer from hard water.

Ion water filters

Ion water filters remove solid impurities from your water and help soften the water via ion exchange. Softening the water will reduce the amount of calcium build-up in your bidet.

Some ion filters also add negative ions into the water stream that sterilize the water and discourage any sort of bacteria growth.

A few ion filters will also include a mechanism to remove chlorine from the water – but not all.

Ion water filters are best for users who suffer from hard water.

Carbon water filter

A carbon water filter uses granular carbon to remove sediments and chlorine from your water stream. It also works to soften your water and prevent calcification of your bidet. The granulated carbon adsorbs (not absorbs) the troublesome elements in your water so they never reach your bidet.

Whether you should remove chlorine from your water supply is up for debate. On one hand, it can be irritating to sensitive skin, but it also helps to keep your water sterile.

About Veronica Fletcher

Veronica has a passion for all things eco-friendly. After growing up on a farm in Ireland, she went on to study Chemistry and Environmental Sciences. Veronica has also volunteered in many sustainability roles, including conservation efforts in Bangladesh and teaching Environmental Sciences to schoolchildren in Kenya.