What causes a toilet to leak from the base when flushing?

A toilet leaking from the base when flushing is most often a failed wax ring seal between the toilet and the floor flange. The usual trigger is a worn, compressed, or misaligned ring that lets discharge water escape only during the flush cycle.

Other causes include loose closet bolts that let the bowl move, a damaged or low-sitting flange, or a hairline crack at the horn of the bowl. If you notice sewage odor or backup at other drains, treat it as urgent because a partial main-line blockage can force water at the base. Our plumbers handle this repair frequently across the Orlando area and often pair it with a quick stability check of the flange and bolts.

Watch for these decision signals:

• A small puddle or ring of water appears after each flush.
• The toilet wobbles or the bolts won’t stay snug.
• Staining or musty odor around the base or grout.
• Water stops when the toilet is not flushed.

Shut off the supply, avoid using the fixture, and have a plumber reseal the base and inspect the flange.

Updated: 2026-06-18

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