How to deep clean a dishwasher — with top tips from a cleaning expert

A woman emptying a dishwasher filled with colorful plates
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You may be wondering why you need to deep clean a dishwasher when its sole purpose is to leave your pots and pans sparkling clean. With so much hot water and detergent moving around the tub, surely there’s not a spot that goes untouched.

Despite a dishwasher’s best intentions, food residue, soap scum, and grease can build up inside the tub and make it difficult for water to move around. The drainage pipe can also become blocked, leaving excess water in the tub, creating bad odors, and encouraging bacteria.

Even if you have one of the best dishwashers, it will still appreciate a regular deep clean to keep it working at its best, and keeping on top of maintenance will also help prolong its life.

Here, Marla Mock, President of Molly Maid, shares her top tips on how often to clean a dishwasher and how to do it.

How often should you deep clean your dishwasher?

An open dishwasher

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Mock recommends cleaning your dishwasher once a month to keep it in tip-top condition. This will prevent any build-up of food residue, grease, and soap scum, which can affect its cleaning performance and lead to other issues, such as blocked drains and filters and bad odors.

How to deep clean a dishwasher

Empty Dishwasher

(Image credit: Future)

Rather than taking on the dishwasher in one swoop, Mock breaks the cleaning chores into sections to make life easier. From cleaning the filter, to cleaning the drain, here’s how to do it.

Cleaning the filter

Hand holding dirty dishwasher filter by open dishwasher

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1. To get started, Mock says to remove the bottom rack of your appliance and locate the filter, which is usually at the bottom of the tub.

2. Then, she advises, “Lift out the filter and rinse it under warm water to remove any food particles or debris."

3. To give the filter a deep clean, Mock recommends soaking the filter in a solution of warm water and white vinegar for about 15-20 minutes.

4. Grab a soft brush and dislodge any remaining food debris.

5. Finally, thoroughly rinse the filter and reinstall it back into your dishwasher.

Cleaning the gasket

Woman inspecting gasket on dishwasher

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1. Mock says to start by inspecting the rubber gasket around the dishwasher for any dirt or grime build-up. You’ll probably be surprised at what you find.

2. Wipe around the area with a damp cloth soaked in warm water and mild dish soap. “Pay special attention to the folds and crevices where debris may accumulate,” says Mock.

3. Rinse the gasket with clean water and dry it thoroughly with a towel.

Cleaning the racks

Open dishwasher showing lower rack pulled out

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1. Mock says to remove the racks from the dishwasher and inspect them for any food particles or stains.

2. Take a sponge or soft brush soaked in warm, soapy water and give the racks a wipe.

3. Then create a paste using baking soda and water for stubborn stains. Apply the paste to the stains and leave it to sit for a few minutes before scrubbing.

4. Finish by rinsing the racks in water and reinstalling them back into the dishwasher.

Cleaning the spray arms

Man removing dishwasher spray arm

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1. Remove the sprayer arms from the dishwasher and inspect them for any clogs or debris.

2. Mock suggests taking a toothpick or small brush to dislodge any food particles stuck in the spray holes.

3. If debris remains, she suggests soaking the sprayer arms in a solution of warm water and vinegar for about 15-20 minutes to dissolve any mineral deposits.

4. Finish by rinsing the sprayer arms with clean water and reinstalling them into the dishwasher.

Finish Dual Action Dishwasher Cleaner (4-pack): $19 at Amazon

Finish Dual Action Dishwasher Cleaner (4-pack): $19 at Amazon
Use this Finish dishwasher cleaner once a month to remove grease, limescale and odors from your appliance. Simply, remove the cap and place the container upside down in your dishwasher, before running an empty cycle on the hottest setting (minimum 125°F).

Cleaning the door and internal walls

A woman cleaning a dishwasher with a cloth

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You can follow the same steps to clean the dishwasher door and the internal walls.

1. Wipe the inside and outside of the dishwasher door with a damp cloth soaked in warm, soapy water, paying attention to the edges and corners where dirt and grime accumulate.

2. For stubborn stains or grease, Mock recommends using a paste made of baking soda and water. Apply it to the affected areas, and let it sit for a few minutes before wiping clean.

3. To complete the clean, rinse the door with clean water and dry it thoroughly with a towel.

Cleaning the drain

1. Begin by removing the bottom rack and checking the drain area for any food particles or debris.

2. Take a damp cloth or sponge to wipe away any visible debris.

3. For a deeper clean, Mock suggests pouring a mixture of baking soda and vinegar down the drain to break up grease and food residue. The solution should be left to sit for about 15-20 minutes before flushing the drain with hot water.

4. Reinstall the bottom rack once the drain is clean.

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Camilla Sharman
Staff Writer, Homes

Camilla Sharman has worked in publishing and marketing for over 30 years and has covered a wide range of sectors within the business and consumer industries both as a feature, content, and freelance writer.  

As a business journalist, Camilla has researched articles for many different sectors from the jewellery industry to finance and tech, charities, and the arts. Whatever she’s covered, she enjoys delving deep and learning the ins and out of different topics, then conveying her research within engaging content that informs the reader. In her spare time, when she’s not in her kitchen experimenting with a new recipe, you’ll find her keeping fit at the gym. In the pool, stretching at a yoga class, or on a spin bike, exercise is her escape time. She also loves the great outdoors and if she’s not pottering about in her garden, she’ll be jumping on her bike for a gentle cycle ride.