Why Do Clothes Smell After Washing? The Real Causes and Fixes

October 22, 2026 C.B. Shaw

Why do clothes smell after washing? Mostly bacteria. The musty, “wet dishcloth” smell is produced by microbes that survive a cool wash and then multiply while the fabric stays damp. A dirty washing machine can add to it, but research suggests it is not the whole story. The practical fix is the same in almost every source: dry clothes promptly and fully, use the right amount of detergent, wash smelly items warmer when the fabric allows, and keep the machine clean.

The bacteria behind the smell

Researchers in Japan (Kubota et al., 2012) identified Moraxella bacteria as primarily responsible for the “wet-and-dirty-dustcloth” odor of indoor-dried laundry. One odor compound linked to the species is 4-methyl-3-hexenoic acid. We could only read the titles and a later review, and that review suggests Moraxella may not be the only culprit. Think of it as a lineup with more than one suspect.

A 2021 review in Microorganisms (Zinn, Singer and Bockmühl) reports that a combination of three skin bacteria produced strong wet-fabric odor in a lab model, via compounds including dimethyl disulfide, dimethyl trisulfide and indole. Body fats left on cotton drive it, and the odor is more common at lower wash temperatures and with slow or indoor drying. A study in five Belgian homes (Callewaert et al., 2015) found that a 86°F cycle with no bleach left lots of surviving bacteria, and skin bacteria were enriched on washed cotton. Interestingly, bacteria from the machine's water biofilm rarely transferred to the clothes, so the washer may matter less than people assume. It was a small study, five homes, so it's a clue and not a verdict.

Fiber matters too. Zinn's review says fiber content is a major factor in residual body odor, and “polyester holds odor” is directionally true with medium support. The 2014 paper behind that claim wasn't one we cracked open, so hold it loosely. For more on polyester, see polyester vs nylon vs spandex.

The front-loader lawsuit

Here's the history other posts skip. In 2006, Sears customers filed a class action over Whirlpool-made front-loaders (Whirlpool, Maytag and Kenmore, made 2001 to 2010), alleging mold grew in the gaskets and that the machines were defectively designed not to self-clean. NBC News reported that counsel said water splashed into crevices at the back of the tub but did not flush it. Neither company admitted fault. The case settled around 2016, with notices going to about 5.5 million people. A separate LG settlement covered 2002 to 2006 washers. The point: the problem was widespread and was blamed on design, not user error. Consumer Reports says many high-efficiency top-loaders perform nearly as well as front-loaders, and that high-efficiency models can smell too.

Why do modern washers use so little water? US federal efficiency standards started with a 1987 law (first standard 1988) and tightened in 1994, 2004, 2011 and later tiers, mainly through higher spin speeds and less water, per the Appliance Standards Awareness Project.

Fixes, ranked by evidence

Fix	What we found
Dry fully and promptly	Supported by Kubota, Zinn 2021 and university extension advice. Best-supported.
Wash smelly items warmer	Zinn's review says 122°F and above reduces bacteria well. Check care labels first. See which wash temperature to use.
Less detergent, low-suds HE type	Advised by a university extension expert answer, because residue builds up. More detergent is not cleaner.
Clean the machine monthly	Extension and Consumer Reports advise the clean cycle or a hot cycle, wiping the gasket, and leaving the door and dispenser open between loads.
Vinegar in the wash	Lab work (Zinn and Bockmühl, 2020) showed vinegar improved reduction of some bacteria at 0.75 percent acetic acid, but that was disinfection, not odor. Vinegar as an odor cure is still a rumor with a good publicist. Never mix vinegar with bleach.
Baking soda, oxygen bleach	Commonly recommended, but no study turned up. Unproven.

Related: a smell that returns when you sweat is often a different story (see why shirts get yellow armpit stains). And if your whites are going dingy too, read why white T-shirts turn gray.

Laundry smell myths, graded

“Musty smell means your washer is moldy.” Partly true. It can be, but bacteria on the fabric and slow drying matter, and one study found little biofilm transfer.
“Only front-loaders smell.” False or unproven. Consumer Reports says high-efficiency top-loaders can too.
“Vinegar cures it.” Unproven for odor.
“More detergent means cleaner.” False per extension guidance.
“Hot water kills the smell.” True for bacteria at 122°F or more, with fabric caveats.