How To Clean A Dishwasher Properly (Step-by-Step Guide)

It's not unreasonable to assume your dishwasher is entirely self-cleaning. After all, it does a great job of getting our plates and cutlery spick and span. 

Unfortunately, it's not that simple. Even your dishwasher needs a helping hand from time to time.

Today, we're showing you how to clean your smelly dishwasher inside and out. It's going to look and clean better than ever. 

By the end of this article, you'll know the step-by-step method for cleaning a dishwasher, including the one step people often forget. 

Editor's Note: This post was originally posted in November 2018 and has been completely revamped and updated for accuracy and comprehensiveness in January 2026.

How do dishwashers work?

Before we begin, it's helpful to understand how dishwashers actually work. You'll understand which parts of the machine need cleaning, and, more importantly, why.

• Water enters the dishwasher at the base until a shallow pool of water forms. 
• Heating elements at the bottom of the machine raise the water temperature to around 60ºC.
• This water is then pumped to the spray arms at the bottom and top of the machine, where the water pressure increases, forcing it through the holes in the arms.
• The water washes your dishes, then drains back down.
• Any food debris is collected in the filters at the bottom of the machine, before being pumped back around.

How to clean a smelly dishwasher

Luckily, it's super easy to clean your dishwasher, so let's get started. 

1. How to clean dishwasher filters

Have you ever wondered where all the bits of food on your plates, pots and cutlery go in the dishwasher?

Dishwasher filters at the bottom of the machine catch and collect food debris that comes off during the wash cycle. This prevents food from clogging the drain and being redistributed onto your plates.

If you have self-cleaning dishwasher filters, you won't need to remove them periodically. Manual filters, however, need to be taken out and cleaned.

TOP TIP: Self-cleaning filters will be covered in a raised plastic grid, whereas manual filters will be a small, plastic cylinder at the bottom of the machine, surrounded by a metal mesh.

To clean manual filters:

• Remove the bottom rack, then you'll see the filter below.
• Remove any caps or covers, then turn the filter counterclockwise, and it will come out. It might not be a pretty sight!
• Place both the plastic cylinder and the metal mesh in the sink. While you're here, remove the cutlery basket and let all the pieces soak in a sink full of warm, soapy water.
• Wash the filter cylinder with a scrubbing brush under running water, and rinse the metal filters thoroughly. 
• Once you've cleaned the filter, pop it back in position and tighten it clockwise. Make sure it's nice and secure. 

We recommend cleaning the filter every 1-2 weeks, depending on how often you use your dishwasher. 

2. Cleaning the spray arms

The spray arms are located at the bottom and top of your dishwasher. Water is ejected through small holes along the spray arms to clean your plates.

Hard water can build up in and around the holes, and the arms themselves can become gunky.

If you have a container big enough, you can soak the spray arms in white vinegar to help break down any mineral deposits. If not, you can soak a cloth or kitchen roll in white vinegar and wrap them around the jets. Leave the vinegar to work for 15-20 minutes. 

You can then use a pin or a scrubbing brush to help dislodge any buildup in the spray holes. This should break down any limescale, allowing the jets to perform efficiently. 

Give the spray arms a final rinse and then reinstall them in your machine. We recommend cleaning the spray arms every 3 to 6 months to maintain optimal performance. 

3. Don't forget the rinse aid compartment

This is the step people often forget. The rinse aid compartment can become sticky or clogged over time, especially if rinse aid spills during refills. 

To clean it, open the rinse aid cap and wipe around the opening with a clean cloth or paper towel. If there's any residue or buildup, use a cloth dipped in warm, soapy water to gently clean the area, then wipe dry. 

Keeping this area clean helps ensure rinse aid is released properly during wash cycles, improving drying performance and reducing water marks on your dishes. 

4. Run a cleaning cycle

Slide the racks back in, then pop the cutlery tray in on its side, ready for a deep clean. 

Simply fill a dishwasher-safe jug or bowl with 2 cups of distilled white vinegar and place it on the top shelf of your empty dishwasher. Then run the hottest cycle possible to blast through hard water buildup, remove soap residue, and eliminate any smelly odours.  

Vinegar helps break down limescale, remove soap residue, and neutralise odours. Best of all, it requires almost no effort on your part!

Other acidic liquids can be substituted for vinegar, such as lemon juice. Add one cup of the liquid to a mug and place it on the top shelf of your machine. Run an empty, hot cycle to achieve similar results.

5. Cleaning the door seal

Because your dishwasher spends a lot of its time wet, the silicone seal around the door can easily develop mould if you're not careful. You might also find food spillages here from loading the dishwasher. 

The door seal is easy to keep clean. Just wipe it with a clean cloth, then again with diluted disinfectant. Dry it with kitchen roll. Do this at least once a week.

6. Check the dishwasher drain

If your dishwasher drain smells bad or isn't draining properly, it's worth taking a quick look at the drain area.

With the bottom rack removed and the filter taken out, visually inspect the drain at the base of the machine. Remove any trapped food, labels, or debris using kitchen paper or gloves.  

7. Don't forget to clean the outside 

Once the inside of your dishwasher is looking glorious, it's time to get the outside gleaming, too. 

You'll be pleased to know this is much easier than the interior. To remove any dirt and stuck-on food, wipe down the surface with a clean cloth and warm, soapy water. 

8. Does your dishwasher need a deep clean?

If your dishwasher still isn't as clean as you'd like, it's time to turn to another kitchen cupboard staple: baking soda. 

Like vinegar, baking soda is a deodoriser and slightly abrasive. It'll naturally remove any lingering odours from inside the machine, making it a great homemade dishwasher cleaner. 

Remove the bottom rack and sprinkle baking soda over the bottom of the machine. Replace the rack, then run the empty dishwasher on the hottest cycle available. 

9. Leave the door ajar between washes

One simple habit that makes a big difference is leaving the dishwasher door slightly open after the wash cycle finishes. 

This allows moisture to escape, helping the interior dry out fully. It reduces the chance of mould forming on seals and prevents musty smells from developing inside the machine.

You don't need to leave it wide open; just a small gap is enough to improve airflow. 

Those are all of our tips for cleaning your dishwasher! Next, read our articles on how long dishwashers last and what to do if your dishwasher isn't drying. For more troubleshooting, find out how to fix your dishwasher when the pods aren't dissolving. 

 That's a wrap! How do you keep your dishwasher as clean as the dishes that come out of it? Let us know in the comments below.