Why Your Toilet Keeps Running: Common Causes
A toilet that runs after flushing or turns on by itself is usually losing water through the tank or fill assembly. A quick observation can help identify the symptom, but the exact repair depends on the part that has failed.
Published
Notice when the toilet runs
If it runs immediately after flushing, the flapper, fill valve, handle, or float may not be settling correctly. If it starts on its own after the room has been quiet, water may be slowly escaping from the tank into the bowl.
Check the handle and tank
Make sure the handle returns to its normal position and that the chain is not caught under the flapper. Do not force tank parts or keep adjusting them if the toilet continues to run.
Watch for a larger water-system concern
A running toilet wastes water on a town supply and can cause a well pump to run more often on a private well. If the toilet will not stop, the tank is cracked, or the shutoff valve does not work, have the system checked.
Know when to call
Recurring running, water around the base, a weak flush, or more than one plumbing symptom can point to a repair that needs diagnosis. A plumber can identify the failed component and confirm that the toilet and nearby supply connection are operating safely.
