How to Fix a Running Toilet in 10 Minutes

A toilet that keeps running or refilling is one of the most common household problems — and one of the most searched home fixes. Most of the time it's a cheap, easy repair.

First, take a look

Lift the tank lid carefully and flush. Watch what happens inside. The problem is usually one of three parts: the flapper, the fill valve or the float.

Fix 1: The flapper

The flapper is the rubber seal at the bottom of the tank. If it's worn or warped, water leaks into the bowl and the tank keeps refilling.

1. Turn off the water at the valve behind the toilet and flush to empty the tank.
2. Unhook the old flapper and take it to a hardware store to match.
3. Fit the new flapper and adjust the chain so it has a little slack.

Fix 2: The float

If water flows into the overflow tube, the float is set too high. Adjust it down so the water stops about 2–3 cm below the top of the overflow tube.

Fix 3: The fill valve

If adjusting doesn't help, the fill valve may be worn. Replacement kits are inexpensive and come with instructions.

Check the chain

A chain that's too short holds the flapper open; too long and it can get caught underneath. Adjust it for a small amount of slack.

If the toilet still runs after these fixes, or you see leaks around the base, call a plumber.