What To Do When Your Toilet Won’t Flush

A toilet that flushes properly is easy to take for granted—until it doesn’t anymore. When your toilet won’t flush all the way, keeps running long after you flush, or refuses to flush at all, it can be a huge headache. For many, the thought of calling a plumber out to fix the problem only adds to the frustration. The good news is that many of the problems that interfere with flushing are simple enough that you can fix them on your own.

Here are the four most common reasons your toilet is failing to flush.

1. The toilet is clogged.

A clogged toilet is the most common culprit behind flushing problems, and the one you should rule out first. Use a toilet plunger to either push the waste through so the toilet can flush, or create suction that will pull out any toilet paper or waste that may be stuck in the entrance of the pipe. Once you’ve dislodged the clog, try flushing again.

If your toilet is clogging regularly, make sure you’re not flushing anything that shouldn’t go down the toilet—i.e., anything but toilet paper. You may also want to consider switching to a thinner type of toilet paper if the problem persists.

2. Low water level.

It takes a certain amount of water in the tank to create the siphon effect that flushes waste out of the toilet basin. Not having enough water could lead to a clog, but attempting to unclog your toilet won’t solve this issue.

The water in your tank should come up to about one inch below the top of the tank’s overflow tube. Check the water valve to see if it got turned off by accident. If so, switch it back on and watch to see if the tank refills to the correct level. Then try flushing again.

3. The flapper is damaged.

There rubber flapper inside your toilet tank is designed to block the pipe leading to the bowl below, opening only when the flush lever is pressed to dispense a surge of water that propels waste down the drain. If this flapper becomes bent or warped, it will no longer be able to properly seal the hole or retain enough water to initiate an effective flush.

You can buy a new flapper inexpensively at any hardware store. Drain the tank before swapping out the damaged flapper for the new one. After the tank refills, flush to make sure the problem is solved.

4. Slack lift chain.

The lift chain attaches the flapper to the flushing handle on the outside of the toilet, pulling the flapper open when the handle is pressed down. If the chain has too much slack, it won’t be able to initiate the flush by lifting the flapper.

All you have to do to solve this problem is to shorten the chain so it provides enough pull to lift the flapper open when the handle is flushed. Adjust the chain by affixing it to a hole closer to the flush lever.


If you’ve tried troubleshooting these four common problems and your toilet still isn’t flushing properly, it’s time to call a professional. A Bonfe plumbing technician will be able to diagnose and solve your problem in no time.

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