Does Your Toilet Flush on Its Own? Fix the Ghost Flushing

Last Updated on January 17, 2022 by toilethaven

Why Does My Toilet Keep Flushing By Itself?

So you are home alone in the middle of the night trying to get some sleep then your toilet flushes! No need to scream or call 911. Your toilet is ghost flushing which is also known as phantom flushing. This has nothing to do with ghosts. It describes a condition where a toilet randomly flushes on its own.

A toilet flushing on its own, also known as ghost flushing happens when there is water leaking from the tank to the bowl, usually due to a worn out/warped/dirty toilet flapper. When the water level in the tank gets too low, the float triggers the fill valve to start refilling the tank.

As I have mentioned, most of the time ghost flushing is caused by a worn out/warped/dirty toilet flapper but it can also be caused by other problems like a leaking flush valve seal, leaking tank bolts or even a cracked tank. If there is water on the floor then it is an external leak but if there is no any water then it is an internal leak.

A toilet tank is designed to hold a constant amount of water. The fill valve which is responsible for refilling the tank is connected to the toilet float. The toilet float controls the opening and closing of the fill valve and therefore the water level in the tank.

Whenever the water level in the tank has dropped below a specific point, the toilet float moves down, opening the fill valve which refills the tank. This gives the impression of toilet that is flushing by itself

What Cause a Toilet to Flush By Itself?


1. A bad toilet flapper

A toilet flapper is the rubber seal at the bottom of toilet tank. It sits on the flush valve opening to ensure water does not flow down to the bowl unless during flushing. It is connected to the toilet flush handle arm by a lift chain.

When you push the flushing handle down, the lift chain which was until that moment slack gets some tension and lifts off the flapper allowing water to leave the tank and flow to the bowl via the flush valve.

If the lift chain is too tight, it will slightly unseat the flapper causing water to slowly escape to the bowl causing the toilet to flush on its own.

Hard water causes the flapper to warp and therefore compromise its integrity. Mineral deposits or debris could also be trapped under the flapper inhibiting its effective sealing. As result water will keep seeping under the flapper and cause ghost flushing.

2. The Flush Valve

The flush valve is the opening through which water leaves the tank and enters the bowl. Although not often, the flush valve could get cracked and slowly start leaking water into the bowl. After sometime the water level in the tank will get too low causing the toilet to flush on its own.

3. Leaking toilet tank

This mostly happens at the toilet tank bolts. The toilet tank bolts uses rubber washer to make a water tight seal. Just like the flapper, the rubber washers become worn out with time resulting in a leaking toilet tank.

If unfortunately you toilet tank has a small crack, it will be an expensive repair for you since porcelain will always need to replaced.

With a leaking toilet tank, you will notice water pooling around the base of the toilet.

4. Leaking Water Supply Line

A toilet water supply line is a flexible line that is connected from the shut off valve (back of the toilet) to the toilet tank.

Sometimes the coupling connecting the line to the tank will be dripping water on the flow which will gradually reduce the amount of water in the tank. When too much water has been lost, the fill valve will start to refill the tank to compensate for the lost water.

5. Refill Tube is too Long

The refill tube is a narrow piece of tube that is connected from the fill valve to the overflow tube. During a refill, the refill tube sends a little amount of water back to the bowl.

If the refill tube is too deep inside the overflow tube, it will cause a siphon effect therefore forcing the fill valve to fill the tank after a few minutes.

How to Fix a Toilet That Flushes By Itself


Since a ghost/phantom flushing toilet is not something that is caused by one defective part, the first thing to do is to identify the source of the problem.

Check on the bathroom floor to check if there is any water. If you indeed have water, it means you have a leaking toilet or water supply line.

If you floor is dry, you have an internal leak. To be sure of this, most people put food color in the tank and wait for 30 minutes. If you see the color appear in the bowl, most likely it is your flapper that is leaking. It could also be your flush valve

1. Fix the Toilet Flapper

Since this is the main culprit, we will start with it.

  • Turn off the water supply to the toilet. The shut off valve is located on the wall behind the toilet.
  • Flush the toilet and hold the handle down to remove as much water as possible.
  • Lift off the toilet tank lid. Place it in a safe place where it cannot fall off and break.
  • Check the condition of the lift chain. Is it too tight? Is it slightly unseating the flapper?
  • If the chain looks tight, increase its length a little. It should have a ½ inch slack when the handle is not being operated.Do not however make too slack. If it’s too loose it will be unable to lift the flapper all the way up resulting in a slow and ineffective flush.
  • Disconnect the lift chain from the flush handle arm.
  • Unhook the toilet flapper ears from the flush valve pegs.
  • Remove the flapper and keenly inspect it.
  • If the flapper looks warped and old you will need to replace it.
  • If it however looks to be in good condition but full of dirt and/mineral deposits you can reuse it. Clean it wist water and soft cloth in a sink till its sparkling clean. Use a cloth to also clean the top of the flush valve where the flapper sits. Put the flapper in position and connect the lift chain to the handle arm.
  • If the flapper is warped then you have to replace it. Most toilet flappers are universal and you will only need to buy the correct size according to your flush valve.
  • Install the new flapper and adjust the length of the lift chain. You might have to do this a few times to get it right.
  • Put the toilet tank lid back on and turn on the water.
  • Repeat the food color test to be sure the problem is fixed.

If the flapper was the reason why you toilet was flushing all by itself then this repair should be enough to fix it permanently.

2. Clip the Refill Tube on The Overflow Tube

The refill tube should be clipped on the overflow tube but not be inserted too dip inside. Due to the fact that toilet tanks have different heights, toilet parts manufacturers manufacture them long.

What you should do after buying one is to cut it into an appropriate size according to your toilet tank height. After tat clip it on top of the overflow tube.

3. Replace the Flush valve

If even after replacing the toilet flapper your toilet is still flushing on its own, or you have noticed the crack on the flush valve, you will need to replace the flush valve.

Replacing a flush valve takes more time since you have to remove the toilet tank the install it back. It is always advisable to take that opportunity to also replace the toilet tank to bowl gasket and also toilet tank bolts.

You can also go and extra mile and buy the complete toilet tank repair kit which will also include the fill valve, toilet float and the flapper. This is a detailed guide on how to replace a flush valve.

4. Fix a Leaking Tank

If you toilet tank is leaking, it will most likely be leaking at the tank bolts. Use an adjustable wrench or a combination of a wrench and long screwdriver to tighten the bolts. Sometimes this can stop the leak.

If the bolts are corroded and/or the rubber washers worn out, you will need to replace them with new ones. Replacing toilet tank bolts means removing the tank and reinstalling it later.

Again, while replacing toilet tank bolts you should also take the chance to also replace the tank to bowl gasket. They are sold as complete kit and are inexpensive.

Here is a guide on how to replace toilet tank bolts. If unfortunately the tank is cracked, you will need to by a new one. Make sure you buy the same model or another model compatible with your bowl.

5. Replace the Water Supply Line

If it is the water supply line that is leaking, then that will be and easy and inexpensive repair for you. Turn off the water to the toilet, flush the toilet and remove the leaking line.

As you install the new one do not use a wrench to tight the plastic coupling that connects it to the tank. This can make it to oval and start leaking immediately. It should only be hand tight.


A toilet that flushes on its own wastes a lot of water and the faster you fix it the more water you save and the less the inconveniences. As we have seen fixing a ghost flushing flushing toilet is something you can do comfortably on your own.

if you are not sure you can do it on your own you can always call in a professional plumber or a handyman to do it for you.