How to Fix a Bathroom Sink That Smells Like Rotten Eggs (Even After Cleaning)

Why Your Bathroom Sink Smells Like Rotten Eggs (Even After Cleaning)

If you've thoroughly cleaned your bathroom sink and it still smells like sulfur or rotten eggs, you're likely dealing with one of these hidden issues:

• Buildup of hydrogen sulfide gas from decaying organic matter
• Bacterial colonies inside the drain or overflow hole
• A dry or faulty P-trap allowing sewer gases to rise

Step-by-Step Diagnosis

1. Smell the overflow hole
   Use your nose to check if the odor is coming from the small hole under the faucet. If yes, that's where bacteria may be hiding.
2. Check the drain directly
   Remove the stopper and smell the main drain hole. Shine a flashlight to check for buildup.
3. Run water and listen
   If there's gurgling, the venting or P-trap might be blocked or dry.

How to Eliminate the Rotten Egg Smell

1. Clean the overflow opening
   Mix 1 part bleach with 3 parts water and pour it into the overflow using a funnel. Let sit 10–15 minutes, then rinse with hot water.
2. Flush the drain with baking soda & vinegar
   Pour 1/2 cup baking soda, then 1 cup vinegar down the drain. Cover for 10 minutes, then flush with boiling water.
3. Check and refill the P-trap
   Pour water down the sink if it hasn't been used in a while to seal sewer gases.
4. Use an enzyme-based drain cleaner
   These natural cleaners break down organic material without damaging pipes.

Prevent Future Odors

• Run hot water through the drain weekly
• Clean the overflow every few months
• Use strainers to catch hair and debris
• Keep bathroom well-ventilated

Final Thoughts

The rotten egg smell in your bathroom sink is unpleasant but fixable with the right approach. Don't just clean the surface — go deeper into the plumbing to remove odor-causing bacteria and gases. Try the above steps and enjoy a fresh, clean-smelling bathroom again!