A dishwasher is supposed to clean your dishes, not make your kitchen smell like yesterday's dinner or, worse, a damp basement. If you notice a fishy, sour, or generally funky odor coming from the machine when it’s sitting closed, there’s a good chance something is lingering inside. Food residue, grease, and other organic material can collect in places you don’t immediately see, and the dishwasher’s warm, damp environment can make those odors particularly noticeable, says Noah Pinsonnault, reviews analyst in the Good Housekeeping Institute Home Care & Cleaning Lab.
The good news is that this is usually a problem you can solve yourself with a little targeted cleaning. But before you reach for a heavy-duty cleaner or start taking anything apart, there are a few key spots to check—and a few simple maintenance habits that can help keep the smell from coming back.
1. Clean the dishwasher filter
If your dishwasher smells bad, “the filter is one of the first places I'd check,” says Pinsonnault. Food particles can collect there and begin to smell, particularly when they're left sitting between cycles.
The filter is typically located below the bottom spray arm, so you'll need to pull out the bottom rack to access it. If you're not sure where yours is or how to remove it, check the owner's manual or the manufacturer's website for instructions.
Once you've removed the filter, rinse it under hot running water or swish it around in warm, sudsy water. Use a soft toothbrush to gently scrub the mesh screen and plastic frame, paying attention to any grease or food particles caught in the crevices. Rinse it clean, then lock it securely back into place.
As a general rule of thumb, you should clean your dishwasher's filter about once a week—even when there isn't a noticeable smell, says Pinsonnault.
2. Check the spray arms
Next, take a look at the spray arms. Food debris and mineral buildup can collect in the small holes where water sprays out, so check them for any visible residue or blockages.
If you spot debris or mineral buildup, remove and clean the spray arms according to your dishwasher manufacturer's instructions. Since spray-arm designs vary by machine, the owner's manual or manufacturer's website is the best source for instructions on removing and cleaning them.
3. Wipe down the door and gasket
Food residue, grease, and other buildup can also collect around the dishwasher door, gasket, and dispenser.
For routine weekly cleaning, wipe the door and other interior surfaces with a damp microfiber cloth or sponge. Check the detergent dispenser for food debris or undissolved detergent, too. If you find gunk along the rubber door gasket, gently scrub it away with an old soft toothbrush dipped in warm, sudsy water or a mild all-purpose cleaner.
4. Run an empty cycle with dishwasher cleaner
If you’ve cleaned the filter, spray arms, door, and gasket but your dishwasher still smells, give the machine itself a deeper clean. Run an empty cycle with a dishwasher cleaner, following the product's instructions. This helps remove grease, food residue, detergent residue, and mineral buildup from areas you can't easily reach by hand.
Even if your dishwasher doesn't smell, Pinsonnault recommends running a cleaning cycle about once a month to keep any buildup from accumulating in the first place.
5. Scrape food off dishes before loading
Before loading the dishwasher, scrape excess food from your dishes. You don't need to completely pre-rinse dishes that are going straight into a wash cycle, but it’s helpful when dirty dishes are going to sit in the dishwasher for a while before you run it. Alternatively, you can run a rinse cycle to help keep food from sitting there and starting to smell.
6. Let the dishwasher dry out
After a cycle, leave the dishwasher door slightly ajar when possible. This allows the interior to dry out instead of trapping moisture inside, which can help prevent odors from developing between cycles. Some newer dishwashers have an automatic door-opening feature that does this for you as part of the drying cycle.
7. If it smells like sewage, look beyond the dishwasher
“If you've cleaned the filter and the machine and there's still a persistent bad odor, particularly a sewage-type smell, I'd start thinking beyond normal food buildup,” says Pinsonnault. “There could be a drain or plumbing issue that needs to be investigated.”
Brigitt is a writer, editor and craft stylist with nearly 15 years of experience. She specializes in lifestyle topics, including home, health, parenting, beauty, style, food, entertaining, travel and weddings. She has written for Glamour, People, Good Housekeeping, Women's Health, Real Simple, Martha Stewart, Apartment Therapy, The Spruce, and more.
