Why Does My Toilet Keep Clogging?

An occasional clog is normal. A toilet that clogs again and again has a deeper issue. Here are the most common reasons and what to do about each.

Common causes

• Flushing too much paper or non-flushable items
• A low-flow toilet with weak flush power
• A partial blockage further down the line
• A blocked toilet vent reducing flush strength
• Hard water mineral buildup in the trap or jets
• Tree roots in the sewer line

What to check

If only one toilet clogs, the issue is likely the toilet or its immediate drain. If multiple fixtures back up, suspect the main line. Mineral buildup in the rim jets can also weaken flushes over time.