Skip to Content
Toilets & Seats
Toilet Constantly Leaking or Running
Why is my toilet constantly leaking or running? This troubleshooting document relates to one or two-piece toilets.
Description of Issue
With this issue, water constantly leaks or runs from the toilet tank into the toilet bowl because the trip lever arm may be binding, water may be overflowing into the flush valve overflow, or debris may be lodged underneath the cap of the fill valve.
Symptoms of Constant Leaking or Running
You will hear a constant filling or running noise coming from the toilet tank that does not stop. You may also see a slight ripple of water in the toilet bowl. If you remove the tank lid, you will notice water overflowing into the overflow of the flush valve.
Flapper style toilet (left) and canister style toilet (right)
Corrective Actions:
Clean the fill valve or replace the fill valve.
Flapper style toilet (left) and canister style toilet (right)
Leaking or constant running is often caused by sediment or debris lodged in the cap of the fill valve preventing the water from turning off. The fill valve fills the tank and bowl with water after the toilet is flushed. This issue is common during new toilet installation because turning the water supply on and off can loosen sediment within the water lines.
Replace the fill valve if the toilet is still constantly running after flushing the fill valve. The part number of the fill valve will vary based on the toilet model number.
This video will show you how to flush the fill valve in a KOHLER two-piece toilet in under 10 minutes.
All you will need to perform this maintenance is a plastic cup.
This video will show you how to flush the fill valve in a KOHLER low-profile one-piece toilet in under 10 minutes.
All you will need to perform this maintenance is a plastic cup.
Adjust the trip lever chain for proper slack . The chain should have roughly one to two links of slack so the excess chain does not get caught on the trip lever arm. Remove excess chain if needed.
Adjust tank water level to prevent water from overfilling and running into the flush valve overflow.
If tank water spills into the overflow but eventually stops, the tank water level will need to be adjusted. Reference "Adjust the Amount of Water in a Toilet Tank ."
Click here to identify your toilet model number and to locate parts to service your product.