Quick answer
A leak between the tank and bowl comes from the tank bolt washers or the large tank-to-bowl gasket, both of which wear out, or less often from a cracked tank. Dry the area and watch where the drip forms. Snugging loose bolts a little can stop it, but overtightening cracks porcelain. Worn washers and gaskets are replaced with the tank off. HomeAdvisor puts typical toilet repairs at $150–$391. Call (888) 217-6781 to reach a plumbing company taking calls in your ZIP.
Follow the short menu, then your 5-digit ZIP. The line goes quiet for a few seconds while it connects; stay on. If it does not connect, call once more: companies taking calls change minute to minute.
Written & reviewed by Marcus ReedIICRC WRT
Reviewed November 4, 2026· Next review May 2027
Water dripping from the joint between the tank and the bowl is tank water, so it is clean, but it runs every time the toilet refills and soaks the floor and subfloor around the base over weeks. The cause is nearly always one of two rubber parts, and the main risk is the repair itself: porcelain cracks if you lean on a wrench.
Find Where It Comes From
- 1Dry everything with a towel: the tank, the bolt heads under the tank, and the bowl.
- 2Add a few drops of food coloring to the tank water.
- 3Watch underneath with a flashlight after a flush.
| Where the drip forms | Likely cause |
|---|---|
| At the bolt heads or nuts under the tank | Worn bolt washers, or loose bolts |
| At the center, between the tank and bowl | The tank-to-bowl gasket |
| From a line on the tank wall | A crack in the tank; the tank must be replaced |
| All over the outside of the tank, beads of water | Condensation, not a leak |
| From the supply line or fill valve connection | Supply line nut or fill valve seal |
Fixing It
- Loose bolts: a quarter turn on each nut, alternating sides, can stop a drip. Stop there. If it still drips, the washers are worn.
- Worn washers or gasket: shut off the water, flush and sponge the tank dry, disconnect the supply line, remove the bolts and lift off the tank. Replace the bolts, washers and gasket as a kit, then refit the tank level, tightening evenly by hand plus a little.
- A cracked tank: replace the tank, or the toilet if the tank model is no longer made.
Talk to a plumber about this
One call reaches a plumbing company taking calls in your ZIP.
Why Not to Leave It
A slow drip that reaches the floor goes under the toilet and into the subfloor, where it looks like a failed wax ring. If the floor around the base is soft or stained, see toilet leaking at the base.
What a Repair Costs
HomeAdvisor puts typical toilet repairs at $150–$391. A tank-to-bowl kit is a common job. See toilet repair.
The Call
Call when the bolts are corroded and will not turn, the tank is cracked, or the floor around the toilet is soft. (888) 217-6781 connects you to a plumbing company taking calls in your ZIP. Follow the short menu, enter your 5-digit ZIP and stay on while it connects; if it does not connect, call once more, because the companies taking calls change minute to minute.
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Frequently Asked Questions
Why is my toilet leaking between the tank and bowl?
The rubber washers on the tank bolts or the tank-to-bowl gasket have worn or the bolts have loosened. A hairline crack in the tank is less common.
Can I just tighten the toilet tank bolts?
A small snugging can stop a drip from loose bolts. Overtightening cracks the tank or bowl, so if a gentle turn does not stop it, replace the washers and gasket instead.
Is condensation the same as a leak?
NoIn humid weather a cold tank sweats on its whole surface. A leak shows at the bolts or the joint and continues in dry weather.
Sources
Methodology: How we source and verify data · Report an error
Disclaimer: HearthDry is an independent educational resource. This article is for informational purposes only and does not constitute professional, legal, or insurance advice. Consult licensed professionals before making decisions about your property or insurance claims.