Why Does My Dishwasher Smell? – Reasons Explained

Smell is unquestionably one of the most acute senses possessed by humans. Food is made more appealing with its aroma, and people are more attractive when they smell pleasing.

Contrastingly, when a foul smell triggers our senses, the source of the unpleasant smell becomes unattractive. It wouldn’t do well for kitchen appliances such as a dishwasher to smell foul, especially since it is designed to clean.

Why Does My Dishwasher Smell

Regular, safe dishwashers shouldn’t have a bad odor, but if you notice your dishwasher stinks, it means something has gone wrong internally or externally.

Reasons For The Foul Smell Of Dishwashers

Sewage smell! Musty smell! Sulfur smell! All these are popular smells linked with dishwashers when they start to smell bad. Though the scents do not affect the quality of the dishes washed or even the functioning of the dishwasher, most users are strongly against it.

Why? Because the smell occupies the entire kitchen and can be embarrassing when guests perceive it. Not just that, most people do not want to use dishes that come out of a machine that smells like sewage.

Therefore, it is crucial to get the smell corrected immediately. To do that, you need to know what is causing the smell and why. Here are the four possible reasons for a smelling dishwasher.

1. Rotten Food

When decaying food piles up in the filter of the dishwater or gets stuck in hidden parts of the dishwashers, the ensuing scent may smell like sewage.

Most manufacturers recommend that users clean the dishwasher’s filter periodically, as a fully occupied filter leads to an unpleasant odor. Also, if dirty plates spend too much time in the dishwasher and aren’t adequately cleaned after, they may develop a sewage smell. The odor is quite unpleasant and can become overwhelming if it isn’t corrected.

As sewage smell is mainly related to hygiene, it can be resolved by thoroughly cleaning the dishwasher components. Begin by removing your dishwasher’s filter. If you do not know where the filter is located, read your appliance’s manual to learn where it is and how to detach it.

Then proceed to empty and clean it. Wash with soap and rinse with hot water. Also, wash the environment around the filter with soapy water. Wipe down the door, walls, racks, and gaskets of the dishwasher with hot water, and ensure you reach every corner.

2. Standing Water

If the odor persists, then the smell may be related to drainage issues. Usually, this type of smell would come from both the dishwasher and the kitchen sink as the drainage systems are connected. There must be standing water or food chunks in the pipes, which resulted in the evolution of the rancid smell.

Confirm this reason by disconnecting the shared hose from the dishwater and smell each item separately. If your dishwater doesn’t produce a smell, then the issue is with the drainage hose. The solution lies in cleaning the hose with a stiff, thin wire and a damp cloth. Remove any item stuck on the walls of the hose and rinse several times with hot water.

Then perform a clean cycle to flush out the drain thoroughly. Fill a bowl with 1 cup of white vinegar and set it at the bottom of the dishwasher. Program the dishwasher to run a hot water cycle. The vinegar would break down any leftover particles in the drain and thoroughly flush them out.

3. Mold

It is pretty easy to forget dishes in the dishwasher. Many people temporarily load their dishwasher with the intention of running it when they have enough plates to fill it. This may take longer than planned and lead to the dirty dishes spending days in the dishwasher.

In cases like this, the food on the plates in the dishwasher starts to grow molds and smell rancid. Even when the dishwasher finishes cleaning the dishes, the smell may remain because the molds stick to the dishwasher’s walls and get deposited in tricky corners.

Though the musty smell reduces after every cycle, it would come back with full force once the dishwasher is left alone for a few days. This is because the fungus multiplies during the docile days and reduces when acted on by detergents during cycles.

Reasons Why Dishwasher Smells

The detergent cannot kill the molds completely; therefore, additional actions must be taken to facilitate their total removal. For example, the dishwasher would have to be washed with soapy water and vinegar. Vinegar is very acidic and would make the surfaces of the dishwasher uncomfortable for the fungus.

The organisms can also continue growing on the seals of the dishwasher. This is usually the origin of black slimes on the seals of the dishwasher door. The seals have to be washed carefully and thoroughly to remove the slime.

4. Bacteria

Does your dishwasher smell like sulfur or rotten eggs? Then it is probably a result of the growth of sulfur-reducing bacteria in your dishwasher or kitchen drain.

These bacteria grow in wet, dark environments and release Hydrogen Sulfide (H2S) gases that smell like sulfur and rotten eggs. The smell is overpowering and may leave your entire kitchen smelling unpleasant until it is fixed.

This situation is corrected the same way as the others, by cleaning every part of the dishwasher thoroughly and performing a clean cycle with vinegar. Another way to fix this is by air drying the dishwashers once in a while.

Sulfur-reducing bacteria are anaerobic and so are incapable of living in an oxygen-rich environment. They will only grow if you provide the right conditions for them: wet food particles as substrate and an air-tight, oxygen-deficient environment. Once these factors are gone, the bacteria would be unable to grow.

Habits That Result In A Fresh Smelling Dishwasher

A dishwasher reeks when it is polluted with rotten food, standing water, mold, and bacteria. These are all issues that can be avoided with proper dishwasher hygiene. Here are some tips that can help you keep your dishwasher smelling pleasant and pure.

  • Only load your dishwasher with dirty dishes when you’re ready to perform a cycle.
  • Remove most of the food particles with a spoon before loading dishes into a dishwasher. It is not necessary to rinse the dishes first. Rinsing it first would only lessen the actions of the detergent.
  • Clean the filter every week. It is straightforward and doesn’t take much time.
  • Clean the doors and seals of the dishwasher weekly.
  • Wash the dishwasher with soap and vinegar monthly.
  • Air-dry the dishwasher weekly or simply air it once in a while.
  • Try to run the dishwasher at least once a week. The continuous action reduces the chances of developing a smell caused by rotten food.


When you open your dishwasher, you expect to find either clean sets of dishes that need to be transferred or dirty dishes that require washing. Seeing molds all over the racks and encountering rancid smells would be distressing.

With knowledge from this article, you can prevent unpleasant odors by regularly washing your dishwasher with soap and white vinegar.

When a dishwasher free from food particles is combined with scented dish soap, it results in fresh-smelling dishwater.