A leaking toilet might seem like a small nuisance, but it can quietly waste hundreds of gallons of water and drive up your monthly utility bill. Whether it’s a constant trickle into the bowl or water pooling around the base, these issues often indicate simple problems that most homeowners can fix themselves, without calling a plumber.

In this guide, you’ll learn how to identify the cause of the leak, which tools and parts you’ll need, and how to fix the problem step-by-step, all in plain language. It’s designed for beginners and homeowners who want to save money and time, with easy instructions and a focus on real-world problems people face. This article doesn’t just tell you what to do—it helps you understand why it matters, and how to prevent the problem from coming back.

Why Is My Toilet Leaking?

A leaking toilet can be caused by a few common issues:

• Worn-out parts: Flappers, fill valves, and washers break down over time.

• Loose connections: Nuts and bolts can loosen, especially around the base and tank.

• Clogged or corroded parts: Mineral buildup from hard water can cause parts to malfunction.

• Cracked seals or wax ring: This can allow water to seep out at the base.

Understanding what’s wrong helps you fix it faster—and prevent it from happening again.

How to Tell Where the Leak Is Coming From

Before grabbing your wrench, figure out where the leak is. Here’s how:

1. Check the floor around the toilet base

If you see water pooling there, the wax ring may be bad or the base bolts are loose.

2. Look inside the tank

Is the water level too high? Does the flapper look worn out or loose?

3. Put food coloring in the tank

If the color appears in the bowl after 15 minutes (without flushing), your flapper is leaking.

4. Listen for running water

If the toilet keeps making noise, your fill valve or float may need replacing.

Knowing the source of the leak will tell you which repair method to follow in this guide.

Tools and Supplies You’ll Need

Most toilet leaks only need basic tools and inexpensive parts you can find at any hardware store:

Tools:

• Adjustable wrench

• Screwdriver

• Putty knife

• Bucket and towels

• Plumber’s tape (Teflon tape)

Common replacement parts:

• Toilet flapper

• Fill valve

• Wax ring (for base leaks)

• Tank-to-bowl gasket and bolts

Tip: Buy a universal toilet repair kit if you’re unsure—it usually includes everything needed.

How to Fix a Toilet Leaking from the Base

Water around the base of the toilet usually means the wax ring is broken or the bolts are loose.

Step-by-step:

1. Turn off the water supply behind the toilet.

2. Flush the toilet to empty the tank and bowl.

3. Unscrew the bolts at the base with a wrench.

4. Lift the toilet carefully and set it on a towel.

5. Scrape off the old wax ring using a putty knife.

6. Press the new wax ring into place around the drain on the floor.

7. Reset the toilet, making sure it sits flat.

8. Tighten the bolts evenly—but not too tight or the porcelain may crack.

9. Turn on the water and check for leaks.

Result: A solid seal that prevents smelly leaks and floor damage.

How to Fix a Toilet Tank Leak

Leaks from the tank often come from worn gaskets or loose bolts.

Steps:

1. Turn off the water and flush.

2. Use a wrench to remove the tank-to-bowl bolts.

3. Carefully lift the tank off the bowl.

4. Replace the gasket under the tank and the rubber washers on the bolts.

5. Reassemble, tighten evenly, and turn the water back on.

Tip: Don’t overtighten the tank bolts or you risk cracking the porcelain.

Fixing a Running Toilet

A running toilet wastes water 24/7. The usual cause is:

• A worn-out flapper

• A misaligned float

• A faulty fill valve

Quick Fixes:

• Adjust the float so it stops the fill valve at the right height.

• Check the chain on the flapper—it should have a little slack.

• Replace the flapper if it doesn’t seal properly (see next section).

If these don’t work, replace the fill valve.

How to Replace a Toilet Flapper

Flappers wear out every few years, but they’re cheap and easy to replace.

Steps:

1. Shut off the water and flush to empty the tank.

2. Unclip the old flapper from the overflow tube.

3. Clean the area where the flapper seals.

4. Attach the new flapper and connect the chain.

5. Turn the water back on and test.

Pro tip: Use a flapper made for your toilet model, or buy a universal one.

How to Replace the Fill Valve

If water won’t stop running, the fill valve might be stuck or faulty.

Steps:

1. Turn off the water and flush.

2. Unscrew the water supply line under the tank.

3. Remove the old fill valve from inside the tank.

4. Insert the new one, adjusting the height as needed.

5. Secure it and reconnect the water line.

6. Turn on the water and check for leaks or noise.

This repair usually fixes inconsistent filling or loud hissing sounds.

Tips to Prevent Future Toilet Leaks

Once you’ve made your repair, here’s how to keep things dry long term:

• Check for leaks monthly—look and listen!

• Avoid harsh chemicals—they wear down rubber parts.

• Inspect water levels in the tank after big flushes.

• Replace parts every few years before they fail.

• Use toilet-safe cleaners that won’t damage seals or pipes.

Simple habits can save you from expensive water damage or mold under your floor.

When Should You Call a Plumber?

While most leaks are DIY-friendly, call a pro if:

• The bowl is cracked or moves when you sit on it.

• The leak comes from a wall or floor pipe.

• You notice sewer smells coming from the toilet.

• You tried the steps, and the leak persists.

There’s no shame in calling for help, especially to avoid bigger damage later. Final Thoughts

Fixing a leaking toilet doesn’t have to be stressful, expensive, or require plumbing experience. With the right tools, a little patience, and this easy-to-follow guide, you can solve common toilet leaks in under an hour and save water, money, and peace of mind.

Start small, stay calm, and fix one issue at a time. You’ve got this.

At New Flow Plumbing, we are dedicated to providing our customers with high-quality plumbing services at an affordable price. Our skilled plumbers have the knowledge and expertise to handle any plumbing issue, including leaking toilets. Call us today to set up a service appointment, and let’s handle your plumbing problems.