Why Your Washing Machine Smells Bad (And How to Fix It)

If your washing machine smells bad, the cause is almost always moisture, leftover detergent, or trapped gunk somewhere you don’t usually look. A musty or mildew odor points to mold and residue inside the machine, while a rotten-egg or sewer smell usually points to the drain. Most fixes take under an hour and a bottle of bleach.

TL;DR

Musty smell on a front-loader: clean the rubber door gasket, the detergent drawer, and the drain pump filter, then run the tub-clean cycle.
Use only HE detergent, measured to the line or less. Extra soap leaves film that feeds odor.
Leave the door (or lid) and the detergent drawer open between loads, and unload wet clothes right away.
Sewer or rotten-egg smell: check that the drain hose isn’t pushed too far into the standpipe, and that the standpipe trap still holds water.
If odor survives three weekly cleaning cycles, or smells like sewage throughout the house, call for service or a plumber.

Why Your Washing Machine Smells
Symptom and Cause Chart
How to Fix a Smelly Washing Machine
What Not to Do
When to Call a Professional
How to Prevent It
FAQ

Why Your Washing Machine Smells

Samsung’s support team makes a useful point: apart from a brief new-machine smell, the washer itself doesn’t produce odor. The smell comes from what builds up inside it, which means you can clean it out.

Mold in the Front-Loader Door Gasket

A front-loader seals itself shut with a thick rubber boot, or gasket, around the door opening. Water, lint, hair, and detergent sludge collect in its folds, especially at the bottom (the six o’clock position), and it stays damp long after the cycle ends.

That makes it the number one mold spot. In a Consumer Reports member survey, 17 percent of front-loader owners reported mold, compared with 3 percent of top-loader owners.

A Dirty Detergent Drawer

Liquid detergent and fabric softener leave a sticky film in the dispenser drawer and in the housing behind it. Left alone, that film turns slimy and grows mildew. Whirlpool and Samsung both tell owners to pull the drawer out and clean it regularly, not just wipe the front.

A Clogged Drain Pump Filter

Most front-loaders have a coin-trap or pump filter behind a small panel at the bottom front. It catches lint, hair, coins, and socks before they reach the pump. Anything stuck there sits in a puddle of dirty water between loads and starts to rot.

Too Much Detergent, or the Wrong Kind

High-efficiency washers use far less water than old machines, so regular (non-HE) detergent can’t rinse out completely. Whirlpool notes that non-HE soap leaves a film that causes odor. Even HE detergent causes the same problem if you pour past the MAX line.

Washing Only in Cold Water

Cold water saves energy, but Consumer Reports notes it doesn’t kill mold or other microbes, while hot water can suppress fungi. If every load is cold, nothing in your routine knocks back growth inside the tub.

Closing the Door Between Loads

Shutting the door traps humid air in the drum, and Whirlpool lists it as a direct cause of stale odors in front-loaders. Wet clothes left sitting for hours do the same thing, and they end up smelling too.

Skipping the Cleaning Cycle

Residue also builds up where you can’t reach, like the outer tub, pump, and hoses. That’s what the built-in cleaning cycle is for: Clean Washer on Whirlpool, Tub Clean on LG, Self Clean on Samsung.

How Top-Loaders Are Different

Top-loaders have no door gasket and aren’t sealed airtight, so they get moldy much less often. They still collect detergent film, softener residue, and grime under the rim and around the agitator or wash plate. Whirlpool’s top-loader advice is the same as for front-loaders: HE detergent in HE machines, a monthly Clean Washer cycle, and prompt unloading.

Sewer Smell From the Drain Standpipe

A sulfur or sewage smell is a different problem. Your washer drains through a hose into a vertical pipe called a standpipe, which has a trap below it that holds water to block sewer gas. If the trap dries out, or if the hose is pushed too deep, gas or dirty water can come back up.

Samsung says a drain hose inserted too far can siphon drained water back into the washer, which produces exactly this smell. Their pages cap insertion at 8 inches in one place and 6 inches in another, so 6 inches is the safer target.

The standpipe’s own setup matters as well. InterNACHI, the home inspectors’ association, says a washer standpipe needs a trap and should rise 18 to 42 inches above the trap’s outlet. A pipe that’s too short or has no trap can let odors through.

When It’s Really a Plumbing Problem

If the smell hangs around the laundry area even when the washer isn’t running, or you smell it at other drains, the washer is probably not the culprit. The City of Phoenix’s water department lists dry traps, cracked vent pipes, and loose vent joints as common sources of household sewer odor. Our guide on how to get rid of drain smell covers those household-wide causes in more detail.

Symptom and Cause Chart

Symptom	Likely cause	DIY or pro?
Musty smell, black spots in the door seal	Mold in the front-loader gasket	DIY
Slimy gunk where the drawer slides in	Detergent and softener buildup in the dispenser	DIY
Rotten smell from the bottom front of a front-loader	Clogged drain pump filter	DIY
Suds after an empty rinse, clothes feel filmy	Too much detergent or non-HE detergent	DIY
Sewer or rotten-egg smell while draining	Drain hose too deep in the standpipe	DIY
Sewer smell in the laundry room when the washer is idle	Dry or faulty standpipe trap, vent problem	DIY first (refill trap), then plumber
Musty smell returns after several cleaning cycles	Hidden mold in the outer tub, damaged gasket, or drainage fault	Pro
Burning smell beyond a brand-new machine’s first two cycles	Mechanical or electrical fault	Pro; stop using the washer

How to Fix a Smelly Washing Machine

Work through these in order; most musty washers are fixed by Step 4.

Tools and supplies: rubber gloves, old towels, a shallow pan or baking dish, a soft brush or old toothbrush, microfiber cloths, liquid chlorine bleach (regular, not thickened or splash-less) or white vinegar, a bucket, and a washer tub cleaner such as affresh if you prefer it over bleach.

Safety: Unplug the washer before opening the pump filter panel or reaching into the dispenser housing. Open a window when using bleach, and never mix bleach with vinegar, ammonia, or other cleaners.

Step 1: Clean the Door Gasket

Empty the drum, then run an empty spin-only cycle, as Samsung suggests, to clear standing water. Pick out hair, lint, and any coins or hair ties from the bottom fold of the gasket. LG’s recipe is 3/4 cup of liquid chlorine bleach in 1 gallon of warm or hot water, or vinegar instead of bleach.

Wipe the whole gasket, peel back the lip to clean inside every fold, then towel it dry.

Step 2: Pull and Scrub the Detergent Drawer

Slide the drawer all the way out. On many LG models you press a tab between the bleach and softener cups to release it; check your manual for your model’s release.

Scrub the drawer and any removable inserts with warm water and a soft brush. Then shine a flashlight into the empty drawer housing and scrub any slime you find on its ceiling and walls.

Step 3: Clean the Drain Pump Filter (Front-Loaders)

Unplug the washer. Open the small access panel at the bottom front, lay down towels, and set a shallow pan underneath. If there’s a small drain hose beside the filter, pull its cap and let the water run into the pan first.

Turn the filter counterclockwise to remove it, expecting more water. Rinse it with warm water and a soft brush, clear any debris from the opening, and screw it back until it stops. If you’ve cleaned the trap on a dishwasher that won’t drain, this job will feel familiar.

Step 4: Run the Cleaning Cycle

Select your washer’s cleaning cycle with the drum empty. Add either a washer tub cleaner per its package, or liquid chlorine bleach where your manual says. Samsung, for example, has you fill the detergent compartment to the max line with bleach, not the bleach compartment.

Samsung says Self Clean runs about 1 hour on its top-loaders and about 4 hours on front-loaders. No cleaning cycle? Run the hottest, longest cycle empty with your chosen cleaner.

Step 5: Rinse, Wipe, and Air It Out

Wipe any loosened residue from the drum with paper towels, then run a rinse-and-spin cycle. Leave the door and the detergent drawer open until everything is dry.

For a stubborn musty smell, LG suggests running Tub Clean once a week for three weeks in a row. If the odor is still there after that, it’s time for service.

Step 6: Check for Detergent Buildup

Run a short empty cycle with no detergent or additives and watch the window. If suds appear, there’s soap built up inside; keep running empty cycles until they stop, then cut back the amount you use.

Step 7: Fix a Sewer Smell at the Standpipe

Pull the drain hose out of the standpipe and look at how much was inside. Clean the end if it’s slimy, reinsert it no more than about 6 inches, and secure it with the clip or strap so it can’t slide down. Samsung warns not to remove the hose holder on the back of the washer.

If the washer hasn’t drained in a while, refill the trap by pouring about a quart of water down the standpipe, the same fix the City of Phoenix suggests for any dry trap. If water backs up or drains slowly, the standpipe may be partly clogged, much like a sink that drains slowly.

What Not to Do

Don’t mix bleach and vinegar, or run them in back-to-back cleaning steps without a rinse in between.
Don’t use undiluted bleach on the rubber gasket.
Don’t use thickened, splash-less, or easy-pour bleach in a cleaning cycle. Whirlpool says it can over-suds.
Don’t run a cleaning cycle with clothes, towels, or anything else in the drum.
Don’t use regular detergent in an HE washer, and don’t pour past the MAX line.
Don’t put the pump filter in the dishwasher. LG says to hand-clean it.
Don’t jam the drain hose deep into the standpipe or tape it airtight.

When to Call a Professional

Call the manufacturer or an appliance technician if the musty smell is still there after three weekly cleaning cycles. Hidden mold on the outer tub, a torn gasket, or a draining fault may need parts or disassembly. Consumer Reports found that only 30 percent of surveyed members with mold said they had gotten rid of it, so persistent cases are common.

Also call for service if you notice any of these:

A burning smell that lasts beyond a new washer’s first two cycles. Unplug it and stop using it.
Water left in the drum after a cycle, or drain error codes.
The drain hose holder on the back of the washer is missing or broken.
The gasket is torn or the black spots won’t scrub off.

Call a licensed plumber if the sewer smell continues after you’ve reset the hose and refilled the trap, if you smell sewage at several drains, or if the standpipe overflows when the washer drains. A plumber can check the trap and vent, including a smoke test for vent leaks. We didn’t find a manufacturer or agency source that publishes repair prices, so get a quote before work starts.

How to Prevent It

Keep the inside of the washer dry and free of film with these habits:

Unload clothes as soon as the cycle ends.
Leave the door or lid and the detergent drawer open between loads.
Wipe the gasket and drum dry after the last load of the day.
Use HE detergent and measure it. Concentrated detergents need far less than older formulas.
Go easy on liquid fabric softener, which Samsung links to buildup.
Run the cleaning cycle monthly, or every 30 to 40 loads, or whenever the reminder light comes on.
Clean the pump filter and detergent drawer as part of the same monthly routine.
Check that the washer is level, since Samsung notes an unlevel machine drains poorly.

If you wash almost everything cold, the monthly hot cleaning cycle matters even more. GE Appliances also sells some front-loaders with an UltraFresh vent system designed to remove excess moisture.

FAQ

Why does my washing machine smell like rotten eggs?

A rotten-egg or sulfur smell usually comes from the drain, not the drum. The drain hose may be pushed too far into the standpipe, letting dirty water siphon back, or the trap under the standpipe may have dried out. Reset the hose to about 6 inches deep and pour a quart of water down the standpipe.

How do I get the mildew smell out of my front-load washer?

Clean the door gasket with diluted bleach or vinegar, scrub the detergent drawer, and clear the pump filter. Then run the tub-clean cycle with bleach or a washer cleaner. If the smell lingers, repeat the cycle weekly for three weeks.

Can I clean my washing machine with vinegar instead of bleach?

Yes, LG lists vinegar as an alternative to bleach for wiping the gasket, and Samsung allows white vinegar or bleach in the drum for its Sanitize cycle. Just never use the two together. For heavy mold, a bleach cycle or a dedicated tub cleaner is usually more effective.

How often should I run the washer clean cycle?

Whirlpool and LG both recommend once a month. Samsung says about every 30 to 40 loads, and many machines light up a reminder when it’s due. Run it more often if you wash mostly in cold water or do a lot of laundry.

Do top-loading washers get smelly too?

Yes, though much less often than front-loaders because there’s no airtight door seal. Detergent film and softener residue still build up, so use HE detergent if it’s an HE model, leave the lid open, and run the cleaning cycle monthly.