Toilet Seat Turned Yellow After Bleaching: Why & How To Fix

Bleach is great at disinfecting and making things a bright and clean white. So, it can be confusing as to why a toilet seat turns yellow after cleaning it with bleach.

Bleach can react with other substances or materials, causing discoloration. On white surfaces, such as the toilet seat, but also a porcelain toilet bowl or fabrics, these discoloration spots can look like yellow stains. The only way to fix bleach-yellowed toilet seats is to replace or paint them. 

Read on to learn more about fixing yellow toilet seats, using bleach, and alternative cleaning options.

Why Does Bleach Turn Toilet Seats Yellow?

Sodium hypochlorite, known as chlorine bleach, can discolor plastic and a variety of other materials, turning them yellow. 

The corrosive nature of bleach can react with the polymers that the surface is made of. This chemical reaction results in an undesired change of color. 

The risk of corrosion, damaged finishes, and color changes is even higher if you repeatedly use undiluted bleach on any type of surface, including the toilet seat.

Bleach can settle into the surfaces and in cracks or blemishes, damaging the plastic, chrome, and other materials.

Whenever you use bleach, you should always refer to the product label. It will inform you of what materials you can use it on, how long to let it sit on the surface, and how to dilute it for a variety of needs. 

How To Fix A Yellowed Seat

Occasional cleaning with bleach is generally okay if you follow the instructions and ensure it will work on the surface materials. 

It is recommended that you color test an inconspicuous spot, such as the underneath of the toilet seat first.

If the yellow stain is from urine, mineral deposits, or other material, you can clean it with homemade cleaners. To determine the cause, use a cleaning solution other than bleach and see if you can scrub the yellow away. (See below for cleaning solutions.) 

If you cannot scrub away the stain, then it is likely that bleach has caused the damage.

Yellow staining from bleach cannot be fixed, since the color has been altered due to a chemical reaction, resulting in a permanent change. In this case, you will need to replace or repaint your toilet seat.

Replace The Toilet Seat

Replacing the toilet seat is the quickest and most effective way to permanently remove the yellow stains. After replacing it, do not use bleach to clean it, and opt for alternative cleaning solutions.

This video demonstrates how to remove and reinstall a toilet seat:

Repaint The Toilet Seat

If you choose to repaint the toilet seat instead of replacing it, you will need the following materials:

  • Specialty spray primer and paint (that works with the material that your toilet seat is made out of)
  • Screwdriver
  • Vinegar
  • Dish detergent
  • Spray bottle
  • Towels
  • Non-abrasive soft scrub brush or sponge
  • Fine-grit sandpaper (180-220 grit)
  • Mask
  • Dropcloth

What to do:

  1. Remove the toilet seat from the toilet. 
  2. Rinse all bleach off of the toilet seat before using any other chemicals or cleaners to avoid a reaction.
  3. Spray down and clean the toilet seat with a mixture of equal parts vinegar and dish detergent. 
    • Clean the connection points where the toilet seat joins the toilet as well.
  4. Scrub it with a scrub brush or sponge. The yellow stains will not disappear but you will create a clean surface for the paint to adhere to. 
    • Alternatively, you can use any of the alternative cleaners mentioned below in this article.
  5. Dry thoroughly before the next step.
  6. Wear a mask, and gently sand the surfaces you intend to paint, working in a circular motion. This makes the seat porous for the paint to adhere to it.
  7. Wipe and rinse the seat clean, removing all dust particles. Allow the seat to dry thoroughly.
  8. Spray and evenly coat the seat with primer. Allow it to dry according to instructions.
    • Paint your toilet seat set down on a drop cloth. Consider doing it outside to speed up the drying process. 
    • If you are painting both sides of the seat, you will need to allow each side to dry before turning it over to paint the other side.
  9. Cover the primer with the paint. Follow the use and application instructions on the label. Allow it to completely dry and add a second coat if desired.
    • The paint should be dry before reinstalling the seat back onto the toilet.

Note: Interestingly, yellowing can also result from prolonged sun exposure. UV damage can cause permanent color changes, just like bleaching. In this case, too, you will need to either paint or replace the toilet seat.

How To Avoid Bleach Stains

Once you have replaced or painted a stained toilet seat, you can take steps to avoid this problem again in the future. Other things that can cause non-bleached yellow stains are typically urine or mineral deposits from hard water.  

Limit Bleach Usage

Do not use bleach to clean the toilet. 

If you feel you must, then do not use undiluted chlorine bleach. 

To remove non-bleach stains from plastic, dilute one tablespoon of bleach in one cup of water. Test the solution in an inconspicuous area first. Let the solution sit for up to 10 minutes. Rinse and dry the spot thoroughly. 

If you purchase a commercial bleach cleaning solution, read the label to see if and how to use it on the material that your toilet seat is made out of.

You can also purchase color-safe bleach. Again, make sure it can be used on the toilet seat material, and test in an inconspicuous spot for colorfastness.

All bleach residue must be completely rinsed and off of the toilet seat when done cleaning. Any reminder can cause unsightly yellow stains.

Never mix chlorine with other chemicals, such as ammonia or vinegar. This could create chlorine gas which is dangerous to breathe in. Bleach should always be used in a well-ventilated area.

Use Alternative Cleaners

You can effectively clean your toilet seat to prevent stains and other damage.

Vinegar And Dish Detergent

As mentioned above, you can mix equal parts of vinegar and dish detergent in a spray bottle. Spray it onto the stains. Scrub and then rinse clean.

Baking Soda

Baking soda is a gentle alkaline that can remove stains and eliminate odors. 

Make a paste by mixing baking soda with a little bit of warm water. Apply it to the stains and let it sit for 30 minutes. Scrub with a soft sponge or toothbrush. Rinse clean.

You can also spray the baking soda with vinegar, hydrogen peroxide, or lemon juice before scrubbing. 

Use towels or remove the seat to avoid spills on the surrounding floor.

Coca-Cola Soda

This soda contains phosphoric acid which can help to eliminate stains and build-up. 

  1. Lay down towels around your work area, or remove the toilet seat. 
  2. Dip a clean cloth into the soda and saturate it. 
  3. Lay the soaked cloth onto the stained areas. 
  4. Let it sit for 60 minutes. 
  5. Scrub the areas and rinse clean.

Maintaining Your Toilet Seat Stain-Free

You should clean the toilet seat, especially the underside, every week. Do it more often if it is noticeably soiled. 

You can use any of the cleaning methods above, but if there is no staining, you can also use antibacterial wipes or warm soapy water.

Also, keep your toilet seat out of the direct rays of sunlight. As explained above, the UV light in the sun’s rays can break down the plastic polymers in toilet seats, causing a chemical reaction that results in color changes. 

Many new window installs have double panes to reduce the effects of UV damage. 

However, if you do not wish to install a new window, use a curtain or full window decals to cover the glass and keep the light off of the seat.

Doing this, and wiping the bleach away as quickly as possible when using it, will maintain your toilet seat like new for a long time.