How to Remove Mildew Smell from Clothes for Good

I washed a load of towels one week, and I must have been tired or just not paying attention. They felt dry to me at the time, so I folded and put them in storage, but alas, they were not completely dry.

By the time I was ready to use them, they smelled like they’d been stored in a pond. That sour, swampy funk that hits you when you open the lid and makes you step back. I washed them again. Same detergent, same cycle, hoping the second run would fix what the first one caused. It did not. If anything, they came out smelling worse, like the mildew had decided it lived there now.

It took me three attempts to get that smell out properly. I was treating the symptom and ignoring how mildew actually works. Here is the method that finally worked, and the reasoning behind each step, so you only have to do it once.

Why Do Clothes Smell Like Mildew?

Mildew is a surface fungus that thrives on damp fabric. It needs three things: moisture, warmth, and time. A load left sitting wet in the machine overnight has all three. So do towels that never fully dry between uses, gym clothes balled up in a bag, and laundry rooms with poor airflow.

What surprises people is that rewashing with your normal detergent often doesn’t fix it. Detergent is designed to lift dirt and body oils, not to kill the microbes producing that musty odour. You can run the same load three times and the smell just settles in deeper. If you’re not sure whether you’re looking at mould or mildew on your clothes, the distinction is worth knowing, since mould roots deeper into fabric and needs stronger treatment.

What You Need to Remove Mildew Smell from Clothes

You probably own everything already:

• Distilled white vinegar
• Baking soda
• Your regular laundry detergent
• A large basin or bathtub for soaking
• A clothesline or drying rack, and sunlight if you can get it

Check the care labels before you start. Delicates, wool, and anything labelled dry-clean only should sit this one out. When in doubt, spot-test any solution on a hidden seam first.

Step 1: Sort and Pre-Soak the Worst Items

Separate the smelly items from the rest of your laundry. Don’t mix a mildewed load of towels in with lightly worn shirts. You want maximum water and movement around the affected fabric, and you don’t want the odour spreading to clean clothes.

Fill a basin or tub with the hottest water the fabric allows, and add one cup of white vinegar. Submerge the clothes and let them soak for 30 to 60 minutes. This loosens the residue the microbes left behind and starts breaking down the odour at the source. For an especially bad load, you can soak for a few hours, but don’t leave things sitting all day. Damp fabric is what got you here.

One thing worth knowing: don’t pour vinegar directly into your washer as a shortcut. Whirlpool’s own guidance notes that vinegar is acidic enough to damage the machine over time, and advises rinsing vinegar-treated clothing before it goes in the wash.

Step 2: Wash Hot with Vinegar

Drain the soak, wring the fabric items lightly, and put them in the washer on their own. Add one cup of distilled white vinegar and no detergent. Not a splash, not a capful mixed in with your usual soap. Just vinegar.

Run the hottest cycle the fabric can safely handle. Cotton towels and sturdy fabrics can take real heat. Delicates should follow whatever the care label says, even if that means warm instead of hot. The heat plus the acetic acid in the vinegar breaks down the mildew and neutralizes the compounds behind that musty smell.

Step 3: Wash Again with Baking Soda

When the vinegar cycle finishes, sprinkle one cup of baking soda directly into the drum and run another full cycle, again on the hottest safe setting. Baking soda is alkaline, so it neutralizes whatever odours the vinegar loosened but didn’t finish.

Do these as two separate washes, not one combined load. Vinegar and baking soda neutralize each other almost immediately when mixed, which leaves you with little more than fizzy water and the smell still in your clothes. Sequential is the whole trick.

Step 4: Dry Completely, in Sunlight When Possible

This step matters as much as the washing. Clothes that don’t dry fully will just grow the mildew right back.

If you can, hang everything outside in direct sunlight. UV rays kill the microbes behind the smell, and line-dried laundry genuinely smells better. It works best on natural fibres like cotton and wool. Two caveats: sunlight will fade colours over time, so turn dark items inside out, and bring things in once they’re dry rather than leaving them out all afternoon.

No outdoor space? A drying rack near an open window or a fan works. Whatever you do, don’t put anything in the dryer yet. If any smell remains and you blast it with dryer heat, you risk setting it permanently. Sniff the damp fabric first. If it’s clean, dry as normal. If there’s still a trace of mustiness, repeat the vinegar and baking soda steps once more before the dryer gets involved.

Why the Mildew Smell Keeps Coming Back

If you’ve done all of this and the smell returns within a few wears, your washing machine is probably the source. And if not the washer, then it could be how and where the clothes.

A musty washer hands its smell to everything you put in it. Biofilm builds up on the rubber door gasket and in the detergent drawer, especially in front-loaders, and every rinse cycle can shed microbes back onto clean fabric. You end up treating the laundry over and over while the actual colony sits untouched inside the machine. This is also why scented detergents, dryer sheets, and odour-boosting beads never solve it. They mask the smell. The microbes are still there, which is why the funk comes back the moment the fragrance fades, usually halfway through the day you’re wearing the thing.

If the machine is the culprit rather than the load, you’re dealing with clothes that smell musty straight out of the wash, which points to the washer, not the fabric.

How to Keep Mildew Smell Out of Clothes for Good

The prevention method is boring, but it works:

• Never leave a finished load sitting in the washer. Set a timer if you have to. Thirty minutes is fine; overnight is how mildew starts.
• Don’t ball up damp clothes. Gym gear, wet towels, rain-damp jackets: hang them up or drape them over a rack until wash day instead of stuffing them in the hamper wet.
• Dry everything completely before it goes in drawers or closets. Clothes that feel “almost dry” are still damp enough for mildew.
• Leave the washer door open between loads so the drum and gasket can dry out.
• Measure your detergent. Too little leaves residue for microbes to feed on; too much never fully rinses out and does the same thing.

When to Give Up on a Garment

Most mildew smells come out with the method above. But there are limits. If a garment has visible mould spots that survived two full treatments, or if a delicate fabric is starting to weaken or discolour, it’s time to stop. Take it to a dry cleaner for a professional opinion, or let it go. Some battles aren’t worth the water bill.

The good news: once you understand that mildew is a moisture problem, not a dirt problem, it gets much easier to prevent. Dry things promptly, don’t let wet laundry sit, and deal with the smell the first time you notice it instead of the third.