Why Does My Toilet Keep Running?

A toilet that keeps running after the tank should have refilled usually has a problem with one of the working parts inside the tank: a flapper that isn't sealing, a fill valve that isn't shutting off, a float set at the wrong level, or a chain interfering with the flapper. None of these is usually an emergency, but a toilet that runs continuously wastes water every day until it's fixed, so it's worth checking soon.

What should I check first?

Take the tank lid off and flush once while you watch what happens. The flapper should lift, release the water, then settle back over the opening. The tank should refill and go quiet. If water keeps moving after that, the cycle itself often shows you where the problem is.

Check the flapper

Look at whether the flapper settles completely into place. A worn, warped, or dirty flapper can let water keep seeping from the tank into the bowl, which forces the fill valve to keep replacing it.

Check the chain

The chain needs enough slack for the flapper to close fully. Too tight, and it can hold the flapper slightly open. Too loose, and it can tangle or get in the flapper's way.

Look at the water level

If the tank keeps filling and water runs into the overflow tube, the float or fill valve isn't stopping the incoming water correctly.

Is a running toilet serious?

Usually not an emergency. That doesn't make it ignorable, though, since a continuously running toilet can waste a surprising amount of water.

Can I fix it myself?

Some tank repairs are reasonable DIY work. Replacing a basic flapper or making a simple adjustment is manageable if you're comfortable with it. Don't start pulling the toilet or forcing old connections just because the tank keeps running.

When should I call a plumber?

Consider professional help if:

• Basic tank adjustments don't solve it.
• Water is leaking outside the toilet.
• The toilet moves at the floor.
• The shutoff valve doesn't work.
• The toilet also clogs or flushes poorly.
• You can't tell where the water is going.

Still running after the basic checks? Find Local Plumbing Help