Why Your Guest Bathroom Smells Like Sewer (Fixes)

A sewer-like odor in a guest bathroom is almost always a plumbing or drainage issue. Because guests may notice it immediately, it’s worth treating the smell as a warning sign: even if the problem is small (like a dried-out trap), it can point to a pathway that allows sewer gas to escape into your home.

Below are the most common reasons a bathroom smells like sewer—and practical steps to identify the culprit.