Why is there a sewage smell in your bathroom?

woman holding nose woman holding nose
It's not uncommon for your bathroom to occasionally have bad odors, but if you smell sewage, that's not a good sign. DigitalVision/Getty Images

You walk into your bathroom and crinkle your nose as you detect the faint smell of sewage coming from ... somewhere. While most bathrooms are occasionally home to unfortunate odors, this one is distinctly out of place.

You lean closer to the sink, the shower drain and the toilet as you try to identify the source of the offensive odor. You squeeze some cleaner into the toilet bowl and give it an extra scrub, even though it has been recently sanitized. With that, the fragrance of the cleaner temporarily masks the smell, and you leave the room. Later, you catch another whiff as you walk past the bathroom door. This time, the smell is unmistakable, and no amount of scrubbing, running the fan or spraying air freshener is able to resolve it. So why is there a sewage smell in your bathroom?

The bad news is that any number of things can cause a sewage smell in your bathroom, and it can be difficult to pinpoint the source of the odor. Besides the obvious unpleasant smell, the methane in sewer gas can actually be flammable in large quantities, and breathing it in can be hazardous to your health. Fortunately, once the source of the problem is identified, the sewage smell is usually pretty simple and inexpensive to correct. Want your clean-smelling bathroom back? Read on!