If you’ve ever been in the shower and noticed that the water level in your bathtub is rising instead of draining, you know how frustrating and unsanitary a bathtub backup can be. There are a few common causes of bathtub backups that can be easily fixed with the right tools and techniques.

Hair and Soap Scum Buildup

The most common cause of a bathtub backup is a buildup of hair and soap scum in the drain. Hair, soap, and other debris can get stuck in the drain, preventing water from flowing through it. This can cause the water level in the bathtub to rise, creating a backup.

To fix this problem, you’ll need to remove the drain stopper and clean out any hair and soap scum that has accumulated in the drain. You can use a plunger or drain snake to dislodge any stubborn debris. A mixture of baking soda and vinegar can also be effective at breaking down soap scum buildup.

Clogged Drainpipe

Another common cause of bathtub backups is a clogged drainpipe. This can happen if the buildup of hair and soap scum has accumulated over time, creating a blockage in the pipe. Other items that can clog the drainpipe include foreign objects like toys, jewelry, and even toothbrushes.

To fix a clogged drainpipe, you’ll need to remove the drain cover and use a drain snake to dislodge the blockage. You can also use a plunger to try and force the blockage through the pipe. If the blockage is too stubborn, you may need to call a professional plumber to help.

Sewer Line Backup

In some cases, a bathtub backup can be caused by a sewer line backup. This is a more serious issue that requires immediate attention. If you notice that multiple drains in your home are backing up at the same time, this could be a sign of a sewer line problem.

To fix a sewer line backup, you’ll need to call a professional plumber. They can use a camera inspection to identify the location of the blockage and use specialized equipment to remove it. This is not a DIY project and should only be handled by a trained professional.


In conclusion, a bathtub backup can be caused by a variety of factors, from a buildup of hair and soap scum to a clogged drainpipe or even a sewer line backup. By identifying the cause of the backup, you can take the necessary steps to fix it and prevent it from happening again in the future. If you’re unsure of how to fix the problem or if it’s a more serious issue like a sewer line backup, don’t hesitate to call a professional plumber for help.