A running toilet isn’t just annoying—it can waste hundreds of gallons of water a day and drive up your utility bill. The good news? Most causes are simple to identify and fix with basic tools. This guide walks you through the most common issues and how to repair them quickly.


Step 1: Identify What’s Causing the Problem

✔ Worn or Misaligned Flapper

The rubber flapper at the bottom of the tank can warp, crack, or get coated in mineral buildup. When it doesn’t seal properly, water leaks continuously into the bowl.

✔ Incorrect or Faulty Float

The float controls the water level. If set too high or damaged, the tank can overfill, causing constant running.

✔ Fill Valve Issues

A worn or malfunctioning fill valve may keep sending water into the tank even after it’s full.


Tools You’ll Need

  • Adjustable wrench

  • Screwdriver

  • Replacement parts (flapper, float, or fill valve)

  • Towel or sponge


Step 2: Fixing the Running Toilet

1. Turn Off the Water Supply

Turn the shut-off valve clockwise to stop the flow before working inside the tank.

2. Inspect the Flapper

Remove the tank lid and check the flapper for cracks, wear, or misalignment. Clean or replace as needed — replacements are inexpensive and highly effective.

3. Adjust or Replace the Float

If the water level is too high, adjust the float height. Replace any float that’s waterlogged or not moving freely.

4. Check the Fill Valve

Look for constant water flow, corrosion, or cracks. Adjust the valve or replace it entirely if it no longer shuts off properly.

5. Restore Water and Test the Toilet

Turn the water supply back on, allow the tank to refill, and watch for running or overflowing. Make final adjustments as needed.

6. Replace Parts if the Problem Continues

If small tweaks don’t solve it, replace the affected parts. Modern toilet components are easy to install and affordable.


Keep Your Bathroom Quiet — and Your Water Bill Low

Fixing a running toilet is one of the easiest DIY home repairs. With a little troubleshooting, you can stop the water waste, reduce your utility costs, and regain peace in your bathroom — often in under an hour.

AWP Home Inspections provides buyer’s home inspections in West Central and Central IndianaContact us to request our services.