How to Replace a Toilet Flapper

Download Article

Fix a running toilet within minutes with our complete guide

Co-authored by Patrick Johns and Hunter Rising

Last Updated: October 5, 2024 Fact Checked

Download Article

Removing the Old Flapper

|

Installing the New Flapper

|

Maintaining a Flapper

|

Video

|

Expert Q&A

|

Tips

When water leaks from the toilet tank into the bowl, it’s usually a sign of an old or damaged flapper, which is the large rubber seal at the bottom of your toilet tank. Because running water in your toilet can lead to costly water bills, changing out an old flapper is important for saving money. Luckily, a flapper replacement is a really simple home repair that requires no special tools. Keep reading, and we’ll walk you through fixing your toilet flapper from start to finish so your toilet runs properly again.

Things You Should Know

Turn off the toilet's water supply and flush to empty the tank. Remove the flapper by unhooking the chain from the handle and popping the rubber tabs off the overflow tube.
Get a new flapper that’s the same size as the old one. Hook the new flapper’s chain to the handle and attach the tabs to the overflow tube’s pegs.
Turn your water supply back on and flush your toilet to check the seal on the flapper. If the water stops running, then your repairs are finished.

Part 1

Part 1 of 3:

Removing the Old Flapper

Download Article

1
Turn off the water to your toilet. Locate the metal shutoff valve on the lower part of the wall behind or beside the toilet. Turn the dial clockwise until it stops moving to completely turn off the water so the toilet tank doesn’t refill while you’re working.^{[1]
X
Research source}
- If the valve does not turn by hand, spray it with a lubricant like WD-40 and let it sit for 5 minutes. Try twisting the valve back and forth to loosen it. Just avoid using a pair of pliers since this could damage the valve and cause a water leak.
- You may still hear a slight trickling sound after shutting off the water. This is just the stored water escaping from the tank, not fresh water being pumped in.
- If you’re unable to find a shutoff valve in your bathroom, you may have to disable the water to the house using a supply valve in a basement or utility room.
2
Flush your toilet to empty the tank. Lift the lid off of your toilet tank and carefully set it aside on a towel. Then, flush the toilet and hold down the handle until all the water drains out. That way, you can work unobstructed without getting wet.^{[2]
X
Research source}
- Watch the flapper as you flush the toilet. A functioning flapper will raise and lower smoothly and settle back over the flush valve without creating gaps. If it doesn’t completely close over the tank valve, you may be able to fix the flapper by lengthening the chain attached to it.
Advertisement
3
Disconnect the old flapper from the tank. First, locate the chain connecting the flapper to the toilet’s handle. Unclip the flapper’s chain from the handle lever near the top of the tank. Then, disconnect the flapper from the vertical overflow tube by pulling the rubber tabs off of the pegs.^{[3]
X
Research source}
- When you disconnect the chain, make note of which link was hooked to the handle. Then when you install the new flapper, you’ll know where to connect the new chain to the handle.
- Check for any buildup or scale around the valve after removing the flapper. Clean your toilet tank with vinegar to break up the deposits because they may cause the flapper to leak.

Part 2

Part 2 of 3:

Installing the New Flapper

Download Article

1
Purchase a new flapper matching the size of the old one. Bring the old flapper with you when shopping for a new one to ensure you get one that’s the same style and size. If you’re shopping for flapper online, measure the diameter to ensure you get the right size.^{[4]
X
Research source}
- Look for your toilet’s model number stamped on the inside of the tank. Search for a flapper that’s compatible with the model number to ensure a perfect fit.
2
Connect the new flapper to the flush valve and handle. Set the flapper over the valve opening at the bottom of the tank. Slide the tabs on either side of the rubber seal over the pegs on the valve, and then clip the lift chain to the lower end of the toilet handle lever. Lower the flapper to confirm that it sits squarely over the flush valve and makes a tight seal.^{[5]
X
Research source}
- Double-check that the flapper is secure on the valve and handle so it doesn’t accidentally come loose after a few flushes.
3
Adjust the chain length so the flapper opens and closes easily. Leave enough tension in the chain that the flapper easily lifts up when you flush the toilet, but not so much that it doesn’t seal completely. Give the handle a push and watch the flapper to see if it opens completely. To open the flapper wider, shorten the chain. If the flapper stays open, then lengthen the chain.^{[6]
X
Research source}
- A good rule of thumb is that the ring on the end of the chain should touch or hover just above the bottom of the tank.
- Avoid letting the chain have so much slack that it gets pulled under the flapper when you flush the toilet.
4
Turn the water back on and test out the new flapper. Turn the water shutoff valve on the wall counterclockwise to restore the water and refill the tank. Wait a few moments for the water level to rise well above the flush valve, then press the handle. The toilet should flush immediately and refill the tank. Listen for the water to stop running to make sure the flapper creates a watertight seal. If the flapper works well, then put the lid back on the tank to finish your repairs.^{[7]
X
Research source}
- If the water still runs after replacing the flapper, you may need to fix the fill valve or float instead.

Part 3

Part 3 of 3:

Maintaining a Flapper

Download Article

1
Replace your toilet flapper at the first sign of a leak. As soon as you notice your toilet is running, check the flapper and resolve the issue so you don’t have an expensive water bill. Some tell-tale signs of a failing flapper are a soft hissing sound as water refills the tank, low flushing power, or rippling water in the bowl. You may also have to jiggle the handle to get the toilet to stop running after flushing.
- Toilet flappers usually last around 2-3 years before it’s time to replace them.
Replace the flush valve seal if it appears damaged. If your flapper isn’t causing the issue, look at the rubber ring around the flush valve on the bottom of the tank. If your valve seal looks worn, split, or cracked, pull it out. Then, put a new seal that’s the same size onto the valve. Reinstall the flapper and test your toilet again.
If you’ve done everything you know to do to correct a slow leak and you’re still not sure what’s causing the problem, call in a plumber. They’ll help diagnose the issue and make any repairs that you’re not able to do on your own. Just try to take care of the problem early so you don’t have to worry about more extensive and costly repairs in the future.^{[8]
X
Research source}

Expert Q&A

Search

Add New Question

Question

How do you fix a toilet flapper that won't close?

Patrick Johns
Home Improvement Specialist
Patrick Johns is a Home Improvement Specialist and the Owner of CatchAll Handyman Services. With more than 28 years of experience, he has worked on a variety of home improvement projects, such as carpentry, plumbing, and door and window installations in both commercial and residential properties.

Patrick Johns

Home Improvement Specialist

Expert Answer

Adjust the chain—you always want to make sure there's nothing obstructing it. Check where it opens up and wipe that down to make sure there's no sediment that got stuck. Also, make sure that the chain is not catching on anything.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 0 Helpful 4
Question

I can't unhook the old flapper. It's a very old toilet and seems to be screwed on. Any suggestions?

Nathan Flannery

Community Answer

Maybe a lubricant will help. But you don't want to be rough with an old flapper, since it could crumble into pieces and then the pieces might fall down the pipe and probably clog it.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 3 Helpful 9
Question

What if the water is turned on and the tank does not refill?

Nathan Flannery

Community Answer

It is likely that you need a new fill valve. What is probably happening is that the water isn't getting sufficient force, so it won't go to the pipe where it fills the toilet.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 0 Helpful 3

Ask a Question

200 characters left

Include your email address to get a message when this question is answered.

Submit

Video

Tips

If you suspect your toilet might be leaking but you’re not sure, you can test it by putting a few drops of food coloring in the tank and checking back in the morning. If the water in the bowl has changed colors, you most likely need a new flapper.^{[9]
X
Research source}

Thanks
Helpful 0 Not Helpful 0
Get in the habit of inspecting the flushing mechanisms of each toilet in your home once a year so you’re able to catch potential water flow issues.^{[10]
X
Research source}

Thanks
Helpful 0 Not Helpful 0
If you have a newer toilet that has a dual-flush mechanism, turn the entire flush valve by a quarter turn and slowly lift it up from the tank. If the rubber seals on the valve are damaged, replace them. Otherwise, replace the entire valve.^{[11]
X
Research source}

Thanks
Helpful 0 Not Helpful 0