Dishwasher Smells Bad: Causes and How to Get Rid of the Odor Fast

A bad smell when you open the dishwasher is one of the most common household problems — and usually nothing to worry about. In almost all cases, the machine itself isn't broken; the cause is food residue and build-up that can be permanently removed with a few targeted steps.

Why does my dishwasher smell bad?

According to ÖKO-TEST, a well-known German consumer testing publication, bad odors are almost always caused by food residue building up in the filter, in hoses and pipes, on the floor of the machine, or in corners and crevices. This organic matter is an ideal breeding ground for bacteria and mold, whose metabolic processes produce the typical unpleasant gases. Washing regularly at low temperatures makes the problem worse, since these cycles often aren't hot enough to reliably remove grease and germs.

Cleaning your dishwasher: the fastest fix

The quickest way to get rid of the smell is baking soda combined with a hot cleaning cycle: sprinkle two tablespoons of baking soda on the floor of the empty machine, then run the intensive programme at 65°C or higher. Baking soda neutralises odors, fights bacteria and inhibits mold growth. Diluted citric acid in the detergent compartment also works as an environmentally friendly option against grease and limescale build-up.

Be careful with the door seal: ÖKO-TEST explicitly warns against applying vinegar directly to the rubber door seal — the acid makes rubber porous over time. A damp cloth with a little washing-up liquid is perfectly sufficient for the seal.

Filter and spray arms: the most common cause

The filter basket above the drain at the bottom of the machine collects most of the organic build-up and should be unscrewed and thoroughly cleaned with washing-up liquid and a brush every two to four weeks. The spray arms are also worth checking: clogged nozzles distribute water unevenly and encourage the kind of build-up that eventually starts to smell. On most models, the arms can be removed without tools and rinsed under running water.

Door seal and corners: often overlooked

Food residue tends to collect in the folds of the door seal and in the lower corners of the interior, areas that a normal wash cycle often misses. A quick check after larger loads and a wipe with a damp cloth are usually enough to keep these problem spots clean before permanent build-up forms.

Which temperature and programme actually help?

Bacteria have virtually no chance at 65°C and above — one reason it's worth running at least one intensive programme a month, even if you mostly use economical eco cycles with lower temperatures day to day. Those are energy-efficient, but on their own they aren't enough to permanently remove grease build-up and germs.

How to prevent odors long-term

– Scrape off large food scraps before loading, but skip unnecessary pre-rinsing under running water — modern dishwashers are designed to handle it.
– Clean the filter basket every two to four weeks, rather than waiting until you notice a smell.
– Run an intensive programme at 65°C or higher at least once a month.
– Leave the door slightly open after a cycle so moisture can escape instead of sitting in the closed machine.
– Use rinse aid and enough detergent — too little detergent leaves behind exactly the residue that ends up smelling.

When is it more than just an odor?

If the smell persists despite thorough cleaning, the cause may run deeper: a blocked drain hose, a faulty siphon connection in the kitchen, or a pump that no longer fully removes residual water. In these cases, a professional check is usually the only fix — or, for older machines with recurring problems, comparing against a newer, more efficient model.

Conclusion

Most dishwasher odors can be permanently resolved with baking soda, a hot cleaning cycle and a regularly cleaned filter unit — no harsh chemicals required. Browse our range of current, energy-efficient models under Dishwashers. For help with care or choosing a replacement model, our service team is happy to advise you personally.