How to Clean Mold from a Dishwasher
If your dishwasher smells musty or you see dark spots around the door seal, you may be dealing with mold.
This guide explains how to clean mold from a dishwasher safely, why it grows there, and how to keep it from coming back.
Mold in a dishwasher is usually caused by trapped moisture, food residue, and poor airflow, so the fix is both cleaning and prevention.
The good news: most cases can be handled with common household supplies and a careful routine.
What causes mold in a dishwasher?
Dishwashers create a warm, damp environment, which is ideal for mold and mildew.
When detergent residue, grease, food particles, and standing water collect in hidden areas, spores can grow quickly.
- Food debris: Bits of pasta, rice, grease, and sauce can get trapped in filters and spray arms.
- Moisture: A closed dishwasher holds humidity after cycles finish.
- Poor drainage: Water left in the tub, filter, or hose can feed mold growth.
- Dirty seals: Rubber gaskets around the door can hold grime and moisture.
- Low use: Dishwashers that sit idle for long periods are more likely to develop mildew smells.
How to tell whether it is mold or just mildew?
Mildew is usually a surface-level growth that appears gray, white, or yellowish and is easier to wipe away.
Mold can look black, green, or brown and may spread into crevices, seams, and filters.
If the dishwasher smells earthy or sour, has visible spotting on the door gasket, or leaves residue on dishes, mold is a strong possibility.
In some cases, a combination of mold, mildew, and mineral buildup is present.
What you need before cleaning
Before you begin, gather supplies that are safe for dishwasher components and effective against grime.
- Rubber gloves
- Soft microfiber cloths or sponges
- Old toothbrush or soft cleaning brush
- Dish soap
- White vinegar
- Baking soda
- Small bowl or spray bottle
- Paper towels
Avoid abrasive pads and harsh scrubbing tools that can damage the stainless steel tub, plastic parts, or rubber seals.
How to clean mold from a dishwasher step by step
Follow these steps to remove mold from the visible surfaces and deeper parts of the appliance.
For safety, unplug the dishwasher or switch off the circuit breaker if you need to reach any electrical or hard-to-access areas.
1. Remove and inspect the filter
Take out the dishwasher filter and check it for food buildup, slime, or discoloration.
Wash it in warm, soapy water, then scrub gently with a soft brush to remove trapped residue.
If the filter has stubborn buildup, soak it for 10 to 15 minutes before scrubbing.
Rinse thoroughly and let it dry while you clean the rest of the unit.
2. Clear loose debris from the bottom
Use a paper towel or damp cloth to remove visible food particles, gunk, and standing water from the bottom of the tub.
Pay attention to corners and the area around the drain.
Check the drain opening for blockages.
If water is pooling, a clog may be contributing to the mold problem.
3. Clean the door gasket and edges
The rubber gasket around the door is one of the most common places for mold growth.
Wipe the gasket with a cloth dipped in warm, soapy water, then use a toothbrush to reach folds and creases.
For extra cleaning power, spray or wipe the gasket with white vinegar and let it sit for a few minutes before wiping again.
Dry the area completely when finished.
4. Wash the spray arms
Remove the spray arms if your model allows it and inspect the holes for blockages.
Food particles and mineral scale can reduce water flow and contribute to dirty spots that support mold growth.
Rinse the spray arms under warm water and clear clogged holes with a toothpick or soft brush.
Make sure they move freely before reinstalling.
5. Run a vinegar cycle
Place a dishwasher-safe bowl filled with white vinegar on the top rack of an empty dishwasher.
Run a hot water cycle to help loosen residue, reduce odor, and clean interior surfaces.
Vinegar is useful for cutting grease and helping with odor, but it is not a substitute for physical scrubbing.
Use it as one step in the cleaning process, not the only step.
6. Follow with baking soda
After the vinegar cycle, sprinkle about one cup of baking soda across the bottom of the dishwasher.
Run a short hot cycle.
This can help neutralize odors and brighten the interior.
This step is especially helpful if the dishwasher still smells damp after the first cleaning.
7. Wipe all surfaces dry
When the cycle is complete, open the door and dry the interior with a clean towel.
Leave the door slightly open for a while to let moisture escape.
Drying matters because mold grows when water stays trapped in the tub, gasket, or detergent dispenser.
What should you avoid when cleaning mold from a dishwasher?
Some cleaning methods can damage the machine or create unnecessary safety risks.
Avoid mixing chemicals, and never combine bleach with vinegar or ammonia-based cleaners.
- Do not use steel wool: It can scratch surfaces and leave behind metal fibers.
- Do not overuse bleach: It can harm rubber seals and leave strong residues if used incorrectly.
- Do not ignore hidden parts: Mold often returns if the filter and gasket are not cleaned.
- Do not run the dishwasher while soaking parts: Remove components only if the manufacturer says it is safe.
How to prevent mold from coming back
Once the dishwasher is clean, prevention is mostly about reducing moisture and food buildup.
Small routine habits make a major difference.
- Scrape large food scraps off dishes before loading them.
- Clean the filter at least once a month, or more often if you run frequent loads.
- Leave the door slightly open after cycles to let humidity escape.
- Wipe the gasket and door edges regularly.
- Use the hottest safe cycle occasionally to help reduce residue.
- Check for drainage problems if water remains in the bottom after washing.
You can also inspect the detergent dispenser and utensil baskets for trapped moisture, since mold may appear in those smaller parts as well.
When should you call a professional?
If mold keeps returning quickly, the issue may be more than surface contamination.
Persistent moisture can point to a clogged drain hose, failing pump, or installation problem.
Call a repair technician if you notice any of these signs:
- Standing water after every cycle
- Repeated mold growth despite deep cleaning
- Strong odor coming from the drain area
- Visible damage to the gasket or spray arms
- Leaks around the door or under the appliance
A technician can inspect internal components and confirm whether the dishwasher needs repair, replacement parts, or professional sanitizing.
How often should you deep clean a dishwasher?
For most households, a monthly deep clean is enough to prevent mold, odors, and buildup.
Homes with hard water, heavy cooking, or frequent use may need more frequent maintenance.
Between deep cleans, a quick wipe of the gasket and a check of the filter can keep the appliance in better condition.
Consistent care is the simplest way to avoid another mold problem.