A toilet that won’t stop running can waste 200 gallons a day. Nine times out of ten you can fix it yourself with a $10 part.
Find the culprit
Lift the tank lid. If water is trickling into the overflow tube, your fill valve or float is set too high. If the tank slowly empties into the bowl, it’s the flapper.
Fix the flapper
- Shut the supply valve and flush to empty the tank
- Unhook the old flapper and take it to the store to match
- Snap the new one on and reconnect the chain with a little slack
Or adjust the fill
If it’s the water level, bend or clip the float down so the water stops about an inch below the top of the overflow tube. Turn the supply back on and watch one full cycle.
When to call a pro
If the valve hisses after replacement, the seat is corroded, or the whole assembly is brittle and old, swap the guts entirely — or call us before a slow leak becomes a cracked tank.
Pro Tip
Drop a little food coloring in the tank. If color creeps into the bowl without flushing, it is the flapper — a $10 fix.