Why Is My Toilet Running Constantly? 

A toilet that continues running long after it's been flushed can waste hundreds of gallons of water and increase your water bill. Fortunately, the problem is often caused by one of two common components inside the toilet tank—and both are relatively simple to inspect and repair.


Whether you're a homeowner or a tenant, understanding these common issues may help you identify the problem before requesting maintenance.


1. The Fill Valve Is Set Too High 


The fill valve controls how much water enters the toilet tank after each flush.

If it's adjusted too high, the water level rises above the overflow tube and continuously drains into the bowl. As a result, the fill valve keeps adding water, causing the toilet to run constantly.


Signs of a High Fill Valve 

  • Water is flowing into the overflow tube.
  • The toilet keeps refilling without being flushed.
  • You hear running water long after flushing.

In many cases, lowering the water level by adjusting the fill valve solves the problem.


Need help?


See our Fill Valve Adjustment guide for step-by-step instructions.


2. The Flapper Isn't Sealing Properly 


The flapper is the rubber seal at the bottom of the toilet tank. After you flush, it should close tightly to hold water inside the tank.

Over time, the flapper can become worn, warped, cracked, or coated with mineral deposits, allowing water to slowly leak into the bowl. When the water level drops, the fill valve turns on again, causing the toilet to run repeatedly.


Signs of a Worn Flapper 

  • The toilet randomly refills throughout the day.
  • You hear intermittent running water.
  • The tank slowly loses water after flushing.

Replacing a worn flapper is often an inexpensive repair that can stop the leak and reduce water waste.


Need help?

See our Flapper Replacement guide for step-by-step instructions.


Don't Ignore a Running Toilet 


A continuously running toilet can waste a significant amount of water over time, increasing utility costs and placing unnecessary strain on your plumbing system.


If adjusting the fill valve or replacing the flapper doesn't solve the problem, additional repairs may be needed. Homeowners and tenants should report the issue to their property manager.


Also Read - How can you fix the silent leaks