Dishwasher smells? This is usually the real cause (and how you fix it)

A smelly dishwasher is the kind of problem that almost makes you feel a bit dirty. You open the door and instead of a fresh, clean smell, a musty, sour or even sewage-like smell comes out. Makes sense that you then think: how can something that cleans smell so dirty itself?

The good news is that this is usually not a complicated problem. In most cases the cause is built-up food leftovers, grease, standing water or a filter that has not been cleaned for too long. And even better: you can often solve it fairly simply.

Why does a dishwasher actually smell?

A dishwasher almost never smells "just because". There is usually something building up that you do not see straight away.

The most common causes are:

• A dirty filter: this is where food leftovers, grease and dirt hang around
• Grease and soap residue in the machine: especially in spray arms, rubbers and pipes
• Standing water: often because of a blockage or a poor drain
• A dirty rubber seal: a surprising amount of grime collects there
• Washing at a low temperature too often: handy for energy, but less good for grease and bacteria

That last one is especially important. If you almost always run eco or a low temperature, grease and leftovers dissolve less well. Then a layer of deposit slowly forms in the machine, and that exact layer starts to smell over time.

This is how you get a smelly dishwasher fresh again

Before you go and buy all sorts of things, it is best to do these simple steps first.

1. Clean the filter

Take the filter out of the bottom of the dishwasher and rinse it thoroughly under warm water. If you like, use a soft brush or an old washing-up brush to loosen grease and baked-on leftovers.

If the filter has not been cleaned for a while, this is often already the biggest culprit.

2. Check the spray arms

Food leftovers and limescale can sit in the holes of the spray arms. That means your dishwasher rinses less clean, and dirt stays circulating in the machine longer.

Take the spray arms off if you can and rinse them through. With a toothpick or satay stick you can carefully open blocked holes.

3. Clean the rubber seal

The door seal is the kind of place many people forget. Still, water, grease and dirt often stay behind here.

Wipe the rubber seal with a damp cloth and a little mild cleaner. Look especially carefully in the folds.

4. Run a hot empty cycle

A hot empty cycle helps loosen grease and deposits. Preferably choose the hottest programme on your dishwasher.

You can use a machine cleaner here, or first work once with a simple cleaner as a temporary solution. But if you notice the smell keeps coming back, then a product that is actually meant for machine maintenance is usually simply a lot more effective.

What works better than household remedies?

Online you see lots of tips with vinegar, baking soda or lemon. And honestly: sometimes that helps a bit. Especially if your dishwasher is not very dirty yet.

But with a machine that really smells musty or like sewage, that is often more of a quick freshen-up than a real solution. The smell then simply comes back after a few days or weeks.

That is because the problem usually sits deeper: grease, biofilm and dirt in parts of the machine you cannot easily reach yourself.

That is why a targeted machine cleaner often works better. It tackles dirt throughout the machine, not only what you see on the outside.

If you want to tackle it properly

If your dishwasher smells more often, then regular maintenance really is the difference between "masking it for a moment" and actually solving the problem.

For a thorough clean like that, the Cosmeau Deep Clean Tabs for Dishwasher are a logical option. They help loosen built-up grease, dirt and nasty smells from household machines, so your machine smells fresher again and runs cleaner.

Not a sales pitch, just the practice: if a machine has not been cleaned properly for a longer time, a targeted deep clean usually works better than loose kitchen remedies.

How do you prevent your dishwasher from starting to smell again?

Once the smell is gone, you of course want it to stay that way.

This really helps:

• Clean the filter weekly or every two weeks
• Run a hot programme now and then, even if you normally use eco
• Leave the door slightly ajar after a cycle
• Remove large food leftovers before you put the dishes in
• Clean your dishwasher preventively on a regular basis

Especially that combination of low temperature, a lot of grease and little maintenance is what makes smells come back.

Frequently asked questions

Why does my dishwasher smell like sewage?

That is usually because of standing water, a dirty drain, dirt in the filter or built-up leftovers in the machine. Sometimes the cause sits outside the dishwasher itself, for example at the drain pipe.

Does vinegar help against a smelly dishwasher?

Sometimes a bit, especially with light smells. But with persistent stench it is usually not enough to really tackle grease, biofilm and deeper dirt.

How often should you clean a dishwasher?

Light maintenance, such as cleaning the filter, preferably every 1 to 2 weeks. A thorough clean of the machine itself ideally about once a month, depending on how often you use it.

In short

A smelly dishwasher usually does not mean your machine is broken. It does mean it is dirty in places you do not see straight away. Start with the filter, the spray arms and the rubber seal. And if the smell keeps coming back, choose a real deep clean instead of only a quick patch.

Then your dishwasher smells the way it should again: simply clean.