How to Fix a Running Toilet
Stop a toilet that won't stop running. Usually a simple fix involving the flapper, fill valve, or float.
How to Fix a Running Toilet? Most toilet issues come down to a few common causes. Start by carefully lift the tank lid and set it on a towel on the floor.… Total fix takes 10–20 min.
| Difficulty | Easy |
| Time required | 10–20 min |
| Tools needed | 2 |
Video Tutorial
Tools Needed
Remove the tank lid
Carefully lift the tank lid and set it on a towel on the floor.
Check the flapper
Flush and watch the flapper at the bottom. It should seal completely after flushing. If it's warped, cracked, or doesn't seal, replace it.
Adjust the float
If water keeps running into the overflow tube, the float is set too high. Adjust the float arm or screw to lower the water level about 1 inch below the overflow tube.
Inspect the fill valve
If the fill valve hisses or runs constantly, it may need cleaning or replacement. Turn off the water supply first.
Replace the flapper if needed
Unhook the old flapper from the overflow tube ears. Attach the new one. They're universal and cost $5-10.
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Find Replacement Parts
Canadian retailers first
Adjustable pliers
Replacement flapper (if needed)
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Frequently asked questions
How long does it take to fix a running toilet?
Most DIYers complete this repair in 10–20 min. Difficulty: Easy.
What tools do I need?
You'll need: Adjustable pliers, Replacement flapper (if needed).
Is this safe to do myself?
Yes, when you unplug the appliance first and follow the steps in order. If anything feels unsafe, stop and call a licensed technician.
When should I call a professional instead?
Call a pro if the problem persists after following all steps, if the repair involves gas, sealed refrigeration, or high-voltage components, or if your appliance is still under warranty.