Last Updated on October 5, 2026 by Umar Farooq
Kill it, do not cover it. Brush the growth off outdoors while the fabric is dry, pre-treat the marks, then wash at the hottest temperature the care label allows — adding an oxygen bleach, or a chlorine bleach soak if the fabric is safe for one. Dry the item completely and quickly afterwards, in sun if you have any. Scent boosters and a second rinse will not touch it, because mildew is not a smell. It is a living thing, and it is on your cotton right now.
That last sentence is the whole difference between this problem and every other laundry odour. A musty smell is not residue. It is the by-product of something growing.
Mildew is alive, which changes what you are trying to do
Mildew is a fungus, and Maytag puts the conditions it needs into one sentence on its own support page: “This musty odor might be caused by mildew, a type of mold that thrives in dark, damp places with little airflow” (should you rewash laundry left in the washer overnight?). Three conditions — dark, damp, still. Take away any one of them and growth stops. That is why a wet towel bundled at the bottom of a hamper smells within a day and the same towel on a line in a breeze does not.
Because it is alive, the question is not what dissolves it. It is what kills it, and then what removes what is left behind. The University of Georgia’s textile service is blunt about why this matters beyond the smell: in its upholstery procedure it tells you to “Work cautiously as mildew weakens fibers” (remove stains from mildew, mold). The musty odour is the smell of something eating your cotton. Fabric conditioner cannot negotiate with a fungus.
Why the wash that cleaned everything else left the musty smell behind
A 30 °C cycle with a correct detergent dose is very good at removing soil and very unreliable at killing a fungus sitting inside a cotton yarn rather than on top of it. Removing the organism and removing the odour are also two separate jobs: even where the wash kills it, the dead cell material and the compounds it produced are still in the fibre, and they are what your nose is reacting to. That is the gap a perfume product slots into, and it is why those products feel like they worked for about four hours.
Then there is the loop. Maytag states it in both directions: “Musty odors clinging to your clothes can transfer to your washer, or vice versa, and create a vicious cycle of unpleasant smells.” A single mildewed towel washed with everything else will share the problem out generously, which is why the first instruction below is to run the affected items on their own.
Two things to rule out before you start. If the whole load smells faintly stale and you have never seen a speck of growth on anything, the odds are this is a wash problem rather than a mildew problem — detergent dose, a packed drum, a cold cycle, a load that sat — and that is covered properly on clothes smell after washing. If the drum, gasket or dispenser smells with nothing in it, you are treating the wrong object; start at mold in washing machine instead. Front-loader biofilm is not a niche failing, either: Whirlpool settled class actions covering 5.6 million front-loaders over it and LG settled a parallel case, so if the machine is part of your problem you are in extremely large company.
How to remove mildew smell from clothes that can take heat
This is the full-strength route, and it is for cotton, linen and anything else whose care label permits a hot wash and a bleach of some kind. The procedure below is the University of Georgia Extension’s apparel method, kept in its order, with the reason for each step attached. Read the care label first, because it is the ceiling on everything that follows.
- Brush the growth off outdoors. UGA’s first instruction is literally “Brush off mildew out of doors.” Do it dry and do it outside — the same page’s upholstery section explains why, telling you to brush “outdoors, if possible, to prevent scattering spores in the house.” Wetting it first only spreads a surface deposit into the weave.
- Separate the affected items. They go through on their own, not with the rest of the week’s laundry.
- Apply detergent directly to the marks and launder. UGA: “Apply detergent to stain and launder.” Use the hottest water the label allows, and pick a long cycle rather than a quick one.
- If the stain or the smell remains, soak it. UGA’s figures: “soak for 10 to 15 minutes in a solution of 1/4 cup chlorine bleach (if safe for fabric) or sodium perborate bleach and 3/4 cup water.” Rinse, then launder again.
- If bleach is not safe for the fabric, use the alternative UGA publishes. “An alternative to bleach is to treat with salt and lemon juice and dry in direct sunlight.”
- Inspect the item wet, then dry it hard. Damp fabric hides both a faint remaining mark and a faint remaining smell, and both return as it dries. A tumble dryer will bake whatever is left into the fibre.
One safety line, and it is absolute. Never let chlorine bleach and vinegar meet. Whirlpool prints the rule on its own vinegar page — never use vinegar and bleach together — and the reason is that an acid mixed with sodium hypochlorite releases chlorine gas. Choose one route or the other and rinse thoroughly in between.
The route for fabrics that cannot go hot
Wool, elastane, printed sportswear and anything labelled 30 °C or hand-wash close off the hot-and-bleached option completely, and the honest answer is that what remains works more slowly. Oxygen bleach — sodium percarbonate, sold as a colour-safe laundry booster — is the main tool, and it trades temperature for time. Whirlpool’s instruction for badly affected items is a soak of “up to six hours before washing”, which tells you roughly what you are swapping for the heat you cannot use.
Here is where this page stops short of what the ranking articles claim. No manufacturer, standards body or extension service I could open publishes a temperature at which a mildew colony on cotton dies in a domestic washer. Not one. They all agree on the direction — hotter, longer, drier, with an oxidising bleach — and none of them will attach a number to it, so neither will this page. What you can control precisely on a cool-wash fabric is the drying, and that is the step doing most of the work. Indoors with no dryer that means going after the damp in the room rather than in the garment, which is what a dehumidifier working alongside the airer does: the clothes can only lose moisture as fast as the air around them will accept it.
Repeat the treatment before you accept defeat. Two moderate soaks usually beat one aggressive attempt on a fabric that could not have taken the aggressive attempt anyway, and a badly affected item sometimes needs three passes before the smell stops coming back when it gets wet.
Towels that smell fine dry and musty the moment they get wet
This is the most common version of the complaint by a distance, and towels earn it. A towel is a loop pile engineered to hold several times its own weight in water, it gets folded while fractionally damp, and it then sits in a cupboard — dark, damp, still, all three conditions at once. Breaking any one of those is enough, and in a cold bathroom the cheapest break is a warm bar: a heated towel rail draws about 140 watts and gets a towel dry between showers instead of leaving it damp until the next one. The smell often cannot be detected on a dry towel at all. It arrives the instant you wet it, because wetting is what restarts the thing producing it.
Whirlpool’s towel routine is the sensible one, and it is four moves: wash on the hottest cycle the fabric allows, use a heavy-duty detergent aimed at odour rather than a scented one, soak in an oxygen-based additive for the stubborn cases, then dry them thoroughly — outdoors in sunlight if you can, and on the highest heat the label permits if you cannot. Cycle choice matters more on this load than on any other, which is covered separately on what cycle for towels.
Here is the one strong opinion on this page: a scent booster is not a treatment, and selling it as one is the laundry aisle’s least honest moment. Perfume does not kill a fungus. It buys a few hours while the colony keeps doing what UGA says it does — weakening the fibres it is living in. Use a booster afterwards if you like the smell. Do not use it instead.
What Whirlpool prints, and what the same page warns against
Whirlpool’s mildew-odour article tells you to mix one part white vinegar to two parts water, spray the affected areas, wait 15 minutes and rinse the vinegar out. Further down the same page it says: “It is not recommended to add vinegar to your washer as it is acidic and could cause damage to your machine over time. Make sure to rinse any clothing treated with vinegar before adding them to your washer” (how to get mildew smell out of clothes).
Both halves are true, and the page is not contradicting itself so much as issuing one instruction in two pieces. Vinegar on the fabric, in a sink, rinsed out before anything goes near the drum — fine. Vinegar poured into the machine as a routine — not fine, and Whirlpool and Maytag have both published against that. The reason the distinction keeps getting lost is that most pages repeating the method quote the first half and drop the second.
It is worth knowing where that page sits, too. It carries Whirlpool’s own disclosure: “This article includes AI-generated content that our human team has reviewed and edited to ensure quality.” That does not make the vinegar warning wrong. It does mean a manufacturer blog is no longer automatically first-hand expertise, and it is a decent argument for weighting an extension service’s procedure above a brand’s article wherever the two cover the same ground.
FAQ
What kills a mildew smell in clothes?
Heat plus an oxidising bleach, followed by thorough drying. A hot wash with chlorine bleach where the fabric is safe for it, or an oxygen bleach soak where it is not. Perfume and extra rinses kill nothing.
Can vinegar remove a mildew smell from clothes?
It can help on the fabric, used in a sink and rinsed out. Whirlpool publishes a one-part-vinegar-to-two-parts-water spray with a 15-minute dwell, and the same page tells you to rinse it before the garment goes into the washer. Never combine it with bleach.
Does baking soda get rid of a musty smell?
It helps with the odour and does nothing to the organism. Baking soda neutralises acidic smells, which is why it appears to work, but a surviving colony produces the smell again the next time the fabric is damp.
How do you get mildew odour out of clothes that have already been dried?
Treat it again properly, and expect it to take longer. Brush the item dry outdoors, soak it, wash it as hot as the label allows, and inspect it wet before it goes anywhere near a dryer. Dryer heat sets what is left rather than removing it.
Why do my towels smell musty when they look perfectly clean?
Because they were folded fractionally damp. The smell is undetectable on a dry towel and arrives the second it gets wet, which is a reliable sign that the problem is the drying rather than the washing.
Does sunlight actually kill mildew?
UGA’s carpet procedure allows one or two days of direct sunlight to kill the spores, so the effect is real but slow. On a washing line it is a useful finishing step, not a substitute for the wash.
Is a mildew odour on clothes a health problem?
That is outside what this site can tell you. It is a textile problem here, and the fibre damage is documented. For anything about exposure, ask someone qualified rather than a laundry page.
Dry it faster than it can grow
All of this comes down to two halves that only work together. Kill what is there — heat, bleach, dwell time, in whatever combination the care label permits — then remove the conditions that let it return, which means dry fabric, moving air and light. Do the first without the second and the smell is back within a week. Do the second without the first and you have preserved a colony in excellent condition.
The hamper decides most of this, not the machine. Wet gym kit sealed in a bag on Friday is a four-day culture by Monday morning, and no wash cycle on sale is designed to undo that.
