Why Your Water Smells Like Rotten Eggs

A “rotten eggs” smell—often described as sulfur or hydrogen sulfide—coming from your tap water is a common complaint. While the odor itself can be unpleasant, the underlying cause matters: it may be something as simple as a temporary plumbing issue, or it could be related to the water source or treatment process.

Hydrogen sulfide is the most frequent culprit. It can dissolve in water and release a strong odor when water is running, especially when hot water is used. People also report that the smell may come and go, worsen after water has been sitting, or show up more in one faucet than the rest.