How to Fix a Toilet That Leaks at the Base

How to Fix a Toilet That Leaks at the Base

Water pooling around the base of your toilet is a sign that the wax ring seal has failed — or the toilet is loose on its floor bolts. This needs to be fixed promptly: sewage water leaking under the floor can cause serious damage and mold.

Step 1: Check the Floor Bolts First

Before replacing the wax ring, check if the toilet is loose:

1. Try rocking the toilet gently side to side
2. If it moves, the floor bolts may just be loose
3. Pry off the plastic caps at the base, tighten the nuts with a wrench — snug but don't overtighten (you can crack the porcelain)
4. Flush and check if the leak stops

If the toilet is solid but still leaks, the wax ring has failed and needs replacement.

What You Need

• 👉 Wax-free toilet installation kit — includes seal, mounting bolts, and hardware. Wax-free seals are easier to install and reusable if you need to reset the toilet.
• Adjustable wrench, putty knife, rubber gloves, bucket, sponge
• PTFE tape for supply line reconnection

Step-by-Step: Replace the Wax Ring

Step 1: Turn off the water supply.
Close the shut-off valve behind the toilet. Flush to empty the tank and bowl.

Step 2: Remove remaining water.
Use a sponge and bucket to remove water from the tank and bowl. The toilet needs to be as light as possible.

Step 3: Disconnect the supply line.
Unscrew the supply line from the bottom of the tank.

Step 4: Remove the floor bolt caps and nuts.
Pry off the plastic caps, unscrew the nuts from the floor bolts.

Step 5: Lift the toilet straight up.
Toilets are heavy (50–80 lbs) — get help if needed. Lift straight up to avoid breaking the wax seal sideways. Set the toilet on its side on old towels or cardboard.

Step 6: Remove the old wax ring.
Scrape off the old wax from both the toilet horn and the floor flange using a putty knife. Clean both surfaces thoroughly.

Step 7: Install the new seal.
Following the kit instructions, install the new wax-free seal onto the floor flange. Replace the floor bolts if they're corroded.

Step 8: Reset the toilet.
Lower the toilet straight down onto the flange, aligning the bolt holes. Press down firmly and evenly — sit on the toilet to compress the seal. Don't rock it side to side.

Step 9: Secure and reconnect.
Hand-tighten the nuts onto the floor bolts, then snug with a wrench — alternate sides. Don't overtighten. Reconnect the supply line with fresh PTFE tape on the threads.

Step 10: Test.
Turn water back on, let the tank fill, flush several times, and check for leaks at the base.

Bottom Line

A toilet leaking at the base almost always needs a new wax ring. The repair takes about an hour and the parts cost under $20. Take your time lifting and resetting the toilet — the key is pressing straight down without rocking to get a proper seal.