How to Fix a Leaking Toilet

Stop that running toilet for good

Mike Rodriguez Updated 2025-09-25 15 min 5 steps

Fix the most common toilet leak — a worn flapper valve. This 15-minute repair stops wasted water and annoying running sounds.

15 min

Time Required

$5 – $15

Estimated Cost

Steps

low

Safety

What You'll Need

0/3

Tools

Materials

0/5 Steps0% complete

Step 1 of 5

Diagnose the Leak

Click to zoom

Remove the tank lid. Add a few drops of food coloring to the tank water. Wait 15 minutes without flushing. If color appears in the bowl, the flapper is leaking.

Step 2 of 5

Turn Off Water and Drain

Water supply valve turned off behind toilet

Click to zoom

Shut off the water valve behind the toilet. Flush to drain the tank. Use a sponge to remove remaining water from the tank.

Step 3 of 5

Remove Old Flapper

Removing old toilet flapper from overflow tube

Click to zoom

Unhook the flapper's ears from the overflow tube pegs. Disconnect the chain from the flush lever. Remove the old flapper.

Step 4 of 5

Install New Flapper

Click to zoom

Hook the new flapper onto the overflow tube pegs. Attach the chain to the flush lever with about ½ inch of slack. Too tight = won't seal. Too loose = won't open fully.

Tip

Bring your old flapper to the hardware store to ensure an exact match.

Step 5 of 5