Bathroom Sink Smells like Rotten Eggs

Bathroom Sink Smells like Rotten Eggs [Deal with it Like a Pro!]

The bathroom looks clean, the floor is glittering! No dump clothes around. 

You have used an automatic toilet bowl cleaner, but still, you can't stand the awful smell in there. "What's up?" You ask. Getting closer, you realize that it's the sink. I mean, the bathroom sink smells like rotten eggs!

Well, here's what to know; the awful smell (sulfur) mostly comes from the water or the drain. There are bacteria in the ground, sewage, contaminated water, and pipes that produce hydrogen sulfide gas, which smells like rotten eggs.

To find out the problem, check the rest of the drains in your home too. If the foul smell comes from all of the pipes, then chances are, it might be something in the water supply. However, if the smell is emanating from the bathroom sink drain alone, then the problem might be the pipes in that particular drain.

Let's get into the roots...

What Causes The Sulfur Smell In Your Drain?

The smell in your funky drain can have several possible causes. For instance, if you have not used your drain for a while, it can cause water that is usually trapped in the pipes to evaporate. As a result, the foul smell comes up into your home through the sink.

However, the smell can also be as a result of clogging. A build-up of gunk, hair, and other materials that accumulate within the drain produce the sulfurous gas. When the plumbing vent clogs, the sink drains slowly, and bacteria can build up in the p-trap creating the hydrogen sulfide gas. As such, the bathroom sink smells like rotten eggs. Why?

This gas comes up into your house through the vent.

Is there a proper drain trap installed in your drainage system? Great. However, if you do not have one, that's definitely the reason your bathroom sink smells like rotten eggs. Reason?

Without the P-trap, the smell finds its way into your home.

On the other hand, if grease or cooking fat comes into contact with your bathroom sink, it can get stuck in the drain. Then, solidify to the sides, and as it starts to decompose, its moldy smell can make its way into your house. It often implies that bacteria are growing in the drain.

How to Detect Where the Smell Is Coming From

Wondering how to detect where the smell is coming from when your bathroom sink smells like rotten eggs? Relax. I am going to show you how in just a moment.

To start with, take a clean glass and fill it with cold water from your taps. Get outside and then smell it. Next, head to the water heating system and add water into another clean glass and carry out the same test.

If you smell the eggs rotten odor in both samples, then chances are that the contamination is in the water supply. Nevertheless, if the smell comes from the hot water only, check on the water heater system. Nonetheless, if you don't detect the scent in either of the samples, it could probably be coming from the drain.

So, either call an expert to check on the drain or do it yourself if you are an expert.

What to Do About Sulfur Smell in Drain

1. Hot or Cold Water Contamination

In hot water, the pollution mainly comes as magnesium in the anode reacts with the bacteria that cause the smell. So, replace the magnesium rod with the aluminum one and then disinfect the water in the tank with hydrogen peroxide.

Alternatively, your bathroom sink smells like rotten eggs as a result of contamination of the water in the well and the pressure tank. If so, disinfect them by adding household bleach. Most often, contaminated water softeners cause odors. Therefore consider replacing them.

2. Sink Drain and Drainage Problems

A vent blockage interferes with water flow. In this case, drainage from the toilet or other large water-using fixtures creates pressure that either pushes the sewer gases or sucks the water out of the trap causing the gases to escape. As such, consider unblocking the vent by removing the debris.

In addition, disinfect the sink drain to kill the odor-causing bacteria in the P-trap and the waste pipe. Whenever your bathroom sink smells like rotten eggs, it is good to pour in ½ cup of baking soda and a cup of vinegar.

This will not only clean the sink, but also kill all the bacteria therein.

3. Add Water Filters and Install P-Traps

Dealing with a bad smell could be as simple as installing proper P-traps and water filters in your house. P-trap help prevent the gases from the sewage form making their way into your home. Water filters may only be a temporary fix. Therefore, you will need to consider changing them regularly.

It is important to mark that the water filters may also be the cause of the rotten egg smell. So, you can consider calling a professional drainage system cleaning company to help whenever need be.

Preventing Drain Issues In The Future

Feeling fed up of the sulfur smell in your home? Here are various things you will need to keep your sink from ever having that foul smell again. First, ensure that you clean your drain regularly. Try doing this at least once a month, to ensure that you keep the walls of your pipe clean and free from clogging.

Consider having a sink drain hair catcher, which prevents the hair from going down the drain; thus, causing clogs and odors. Sink drain hair catchers come in different forms. Some are made of silicone and others of stainless steel.

Additionally, to prevent that awkward moment when your bathroom sink smells like rotten eggs to recur, replace your P-trap from time to time. Why? It builds up gunk over time, and you should probably consider replacing it every few years or so.

Nonetheless, hiring a plumber will help fix your drain and do thorough cleaning of your home drainage system.


No one would want to live in a house or a compound that is stinking. It much horrible and unbearable when your bathroom sink smells like rotten eggs. So, find out the cause of the lousy odor and where it’s coming from by doing the above simple tests.

Fix that problem and prevent it in the future. You now have all the tips in your finger tips.

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