Why won't my toilet stop running?
A continuously running toilet is typically caused by a faulty fill valve or a flapper that isn't sealing properly, allowing water to constantly leak into the bowl. This persistent flow wastes water and creates a loud, non-stop noise that disrupts sleep and daily quiet.
What the numbers show
Counted from the threads quoted below. How we count
- Most of it landed at once — the busiest month was September 2026, with 14 people.
- This comes up 17.4× more often in r/Plumbing than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1replacing the fill valve completely2 people mentionedDid this help you?
- 2Lifting the float to test if the water stops2 people mentionedDid this help you?
- 3Replacing the flapper or fill valve assembly2 people mentionedDid this help you?
- 4changing or replacing the fill valve2 people mentionedDid this help you?
- 5adjusting the water level screw2 people mentionedDid this help you?
- 6manually lifting the float armDid this help you?
- 7turning off the water supplyDid this help you?
- 8clearing debris from the fill valveDid this help you?
- 9Having the landlord replace itDid this help you?
- 10Replacing the toilet float part using a YouTube tutorialDid this help you?
- 11replacing the fill valve capDid this help you?
- 12adjusting the float levelDid this help you?
- 13replacing the flush valve sealDid this help you?
- 14doing a full toilet tank rebuildDid this help you?
- 15calling the building maintenance teamDid this help you?
- 16Shutting off the toilet bowl water valveDid this help you?
- 17Adjusting the fill screw counter-clockwiseDid this help you?
- 18Rebuilding the tank multiple times with new kitsDid this help you?
- 19Tightening tank-to-bowl bolts furtherDid this help you?
- 20Using a borescope camera to inspect for cracksDid this help you?
- 21Considering replacing the entire toilet due to the sunken cost fallacyDid this help you?
- 22adjusting the level of water on the fill valveDid this help you?
- 23running a tap to stop the toilet from runningDid this help you?
- 24unplugging the washletDid this help you?
- 25turning off the water supply valve at the wallDid this help you?
- 26Replacing the entire fill valve unit with a new one from a hardware storeDid this help you?
- 27Buying a replacement fill valve kit and changing out all internal componentsDid this help you?
- 28Replacing internal toilet partsDid this help you?
- 29Holding down the handle manually during a flushDid this help you?
- 30Removing the clip and reattaching the refill tube into the top hat of the flush towerDid this help you?
- 31Rotating the lifted valve to adjust slack on the lever's chainDid this help you?
- 32Checking or replacing the leaking flush valve or flapperDid this help you?
- 33Twisting the upper body of the fill valve to adjust its height or checking if the float is caughtDid this help you?
- 34Replacing a faded, worn-out flapper or the seal at the topDid this help you?
- 35Replacing parts using a complete toilet repair kitDid this help you?
- 36Replacing the entire flush or fill valveDid this help you?
- 37Holding the toilet handle down manuallyDid this help you?
- 38Shortening the flapper chainDid this help you?
- 39Readjusting the handle armDid this help you?
- 40Moving the float down slightlyDid this help you?
- 41Changing the fill valveDid this help you?
- 42Replacing the floatDid this help you?
- 43Replacing the flapperDid this help you?
- 44Adjusting the toilet valve by tightening or loosening the screw on the ball cock.Did this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“As you can see water continues to flow, can’t figure out how to stop it. Any ideas?”source ↗
“My toilet was filling constantly. I took apart the fill valve and there was disintegrated rubber so I can't see what should have gone where. Now it doesn't fill constantly, but water comes out under the cap so loud to fill up.”source ↗
“What do I need to get and where do I put it?”source ↗
“Im going to lose my mind. I have a Crane Galaxy toilet that's a few decades old in my guest bathroom. It was slowly leaking from the toilet tank into the toilet bowl. We replaced everything in the tank... and its not nearly as bad as it was but blue food coloring shows its still dripping from the tank into the bowl.”source ↗
“Any advice is appreciated...seriously...spent 2 days doing this.”source ↗
“Hi all! I need to change the cistern washer and first turn the water supply off. Is what I'm looking at a valve? If it is, how do I shut it off?”source ↗
“My toilet is constantly running but inside this small pipe. What should I do?”source ↗
“Does anyone know what I can do to fix it?”source ↗
“My toilet cistern is continously running into the toilet. Also when flushed, it takes a long time to refill aswell.”source ↗
“All of it...took the tank off. Stripped every part off of it, and then got a Fluidmaster kit from Lowes with everything needed to rebuild a toilet.”source ↗
“Having an issue where at night my toilet is overflowing and leaking onto the floor from the integrated cistern.”source ↗
“I have this Kohler Santa Rosa toilet with a Toto Washlet. It has a nonstop hissing noise.”source ↗
“When the hissing first started, I noticed that the tank water level was right at the overflow valve's top, so I turned that screw thing counterclockwide to lower the water level by an inch. But the hissing still remains.”source ↗
“When I initially turn off water supply, the hissing stops. But strongly when I return 20 hours later, the hissing came back.”source ↗
“My water bill shot up. And I believe it’s because my toilets are leaking. Well I completely replaced everything here. And I still hear this water run from time to time even though nobody has used the toilet.”source ↗
“We have to hold down the handle in order for it to completely flush.”source ↗
“When I attach the refill tube to the overflow pipe, it seems to pull up on the flap and leaks water into the bowl.”source ↗
“Keeps running like this constantly”source ↗
“now if I push the toilet handle down it doesn't flush unless I hold it down.”source ↗
“I've adjusted it multiple times but seem to only make it worse. Any advice on how to fix this?”source ↗
“Now though, it’s running every 10-15 seconds. It looks like the issue is something with the fill valve, but idk. Help 😩”source ↗
“Is water supposed to be spraying out from this valve? My toilet won’t stopped running. Do I need to replace the part or is there an easier fix?”source ↗
“My toilet is always either filling constantly or it doesn't fill at all, how do I fix this?”source ↗
“Sounds like you might need a new fill valve”source ↗
“Replace the flapper and fill valve”source ↗
“As the title says, the toilet tank keeps refilling. It started about a week ago.”source ↗
“This is a rental. I can't buy an entirely new toilet.”source ↗
“Just put 2 new flappers on it this weekend...then did all new parts out of a fluidmaster kit...its still leaking.”source ↗
“I’m not familiar with this tank set up and can’t figure the trigger to stop the water from running.”source ↗
“The toilet bowl tank started continuously running non-stop. It flushes okay.”source ↗
“I watched a short video and took a screwdriver to the thing on the left, going counter-clockwise, but it didn’t stop it at all.”source ↗
“I shut the toilet bowl water valve off for now. But what can I do?”source ↗
Where this came up
People with this problem also raised
- 5How to fix a backed up toilet when stores are closed
- 28Why does my toilet keep clogging and gurgling?
- 10Why does my new smart toilet have a weak flush?
- 2Toilet takes 30 minutes to fill up after flushing
- 6Toilet rocks or moves slightly - how to fix
- 6How to get rid of sandy residue and silt in the toilet tank