Musty towels and laundry: how to wash the smell out for good

A towel that smells musty has usually been trapped between a damp wash and a damp closet. Bacteria and mildew feed on the film that builds up in the fibers: detergent that did not rinse out, fabric softener that coats the cotton, and body oils that never fully wash away. Each wash adds a little more, and eventually the towels smell even when they come out of the machine. The smell can also come from the washing machine itself, so cleaning the machine is part of the fix.

The approach below treats the cause rather than the smell. Wash the towels in a way that removes the film, dry them fully and quickly, and store them dry. Most towels recover in one or two washes, and a towel that still smells after a good wash has usually lost its absorbency and should be replaced.

What you need

• A full load of towels or laundry, not an overloaded drum
• Detergent in the amount the packet recommends
• An oxygen bleach product, such as one based on sodium percarbonate, if the fabric allows it
• White vinegar, for the rinse, if you want to use it
• A dryer or a clothesline in a warm, airy place
• A washing machine that has been cleaned recently

Step one: check the machine

Before you blame the towels, look at the washing machine. A machine with mold in the door seal, a dirty drawer or a blocked filter will put the smell back on the laundry. Clean the drawer, wipe the seal, and run a hot empty cycle with a cleaner if you have not done so in the past month. The washing machine guide covers each step in detail.

Step two: wash at the right temperature

Use the hottest water the fabric label allows. Heat dissolves the oils and loosens the film that holds the smell, and cold washes leave more of it behind. Towels and bedding made from cotton can usually take a hot wash. Check the care label for each item, and separate colored items from whites if you are unsure about color fastness.

Heat is not always an option. Synthetic blends and delicate fabrics may need a warm or cool wash, and in that case, rely on the other steps to clean them.

Step three: use the right amount of detergent

Too much detergent is one of the most common causes of musty laundry. Excess soap does not rinse out, and it leaves a film that holds the smell. Measure the detergent carefully, using the amount on the packet for the size of the load and the hardness of your water. In a high-efficiency machine, use a detergent made for it, because standard detergent creates too many suds and can leave residue.

Step four: add an oxygen bleach

Oxygen bleach breaks down stains and odors without the strong smell and fabric damage of chlorine bleach. Add it to the drum or the detergent drawer, following the label for the dose. It works best in a hot wash, and it is effective on the towels that smell of mildew.

Use chlorine bleach only on white cotton and linen that can tolerate it, and never on colored fabrics, wool or silk. Never mix chlorine bleach with vinegar, ammonia or any other cleaning product, because the mixture can release dangerous gases. If you use both, run the bleach in one wash, rinse the machine thoroughly, and then do the vinegar rinse in a separate cycle.

Step five: rinse well

A good rinse removes the soap and the loosened grime that the wash has lifted. If the machine allows it, add an extra rinse cycle to a towel load. A half cup of white vinegar in the fabric softener slot, used in place of softener, can help rinse away soap residue and keeps the fibers absorbent. Do not add softener to towels, because it coats the fibers and makes them less absorbent, and it can trap the smell in the cotton.

Step six: dry them fast and completely

The biggest mistake people make is leaving towels in the drum or in a basket after the wash. Damp towels become musty within hours. Move the laundry straight to the dryer, or hang it up as soon as the cycle finishes.

• Dry towels in a dryer on a warm or normal setting until they are fully dry. Towels that feel slightly damp at the end should be dried for a little longer.
• Hang them on a clothesline in the sun and a breeze if you can. Sunlight helps to kill the bacteria that cause the smell.
• Shake the towels out before you dry them. Loose fibers dry faster and the towels feel fluffier.

Clean the dryer lint screen after drying, because a dryer that is full of lint dries towels more slowly and can leave them damp.

Step seven: store them dry

Once the towels are dry, store them in a closet that is dry and ventilated. A bathroom closet that is damp because of the shower will bring the smell back. Keep the towels off the floor and away from the wall, and open the cupboard door occasionally to let air move through it.

Do not leave towels folded while they are still slightly damp, because the folds trap moisture and encourage mildew.

Bath mats, bedding and gym kit

The same film and damp cause the smell in other items. Bath mats hold water on their underside and need a wash at least once a week, and they should be dried flat or hung over a rail so the back can dry too. Pillows and mattress protectors absorb sweat and skin oils, so wash them at least every few months, following the label, and dry them thoroughly. A pillow that is still damp inside will smell within days.

Gym kit and sports clothes need prompt attention. Rinse sweaty items as soon as you can, and wash them soon after use rather than leaving them in a bag. A soak in a solution of oxygen bleach, following the label for the time and the dose, before the wash can lift the sweat odor that the normal wash leaves behind. Avoid fabric softener on technical fabrics, because it coats the fibers and can hold the smell. Dry the items completely before you put them away, and do not leave them balled up in a kit bag overnight.

Dish cloths and sponges are a separate case. They hold moisture and food, and they need to be washed hot and dried between uses. Replace them often, because no wash removes the bacteria that build up in a tired sponge.

Hanging towels so they dry

Hang towels after each shower so that they dry before the next use. Spread them out rather than bunching them over a rail, and hang them where air can reach them. A towel that stays wet for hours in a warm bathroom is the most common cause of a musty smell.

Using the same towels for a week

Many households use each towel for several days. That is acceptable for bath towels that dry fully between uses, but a towel used for a week without drying will start to smell. If one of your towels smells even after a hot wash and a proper dry, check the fibers. A towel with a sticky texture or a stiff feel has a film that will not wash out, and it is time to replace it.

When to replace the towels

Replace towels that have worn thin, that feel stiff and do not absorb water, or that still smell after two or three careful washes. A towel that has lost its absorbency will stay damp longer, and that damp is what allows the smell to form.

With a clean machine, a hot wash, the right detergent and a fast, complete dry, towels should come out of the wash smelling of nothing at all, and they should stay that way until they are used again.