How to Wash Your Underwear – Temperature and Durability

Short answer: Wash underwear at 30 to 40 degrees with ordinary detergent and no fabric softener, and skip the tumble dryer. That keeps them clean and hygienic while the elastic and the softness last markedly longer. Temperature matters less than people think, and drying matters more.

The right temperature

Forty degrees with an ordinary detergent removes sweat, skin oils and bacteria from underwear. Sixty degrees is not necessary for daily use and puts needless strain on the elastane in the waistband. Thirty degrees cleans well if the item is washed after each wearing, and it is the gentlest temperature for bamboo viscose.

Fabric softener is the worst thing you can do

Softener leaves a film in the fibres that closes off the moisture transport, and that property is exactly what you paid for. Over time it makes the fabric less soft rather than softer, even though the packaging promises the opposite. If an item has gone stiff, it is almost always soap or softener sitting in the fibres.

Drying decides the lifespan

Bamboo viscose is weaker when wet, and the elastane in the waistband does not tolerate heat. A hot dryer halves the life of a pair of underwear, and that is the single factor that matters most. Hang them on a hanger or a line and let them hang until completely dry before folding them.

Dosing and rinsing

Too little detergent leaves dirt behind, too much leaves soap behind, and both produce a fabric that feels stiff and smells sooner. Dose according to water hardness and load size, and use an extra rinse if you have sensitive skin. Soap residue at the crotch is a common and overlooked cause of irritation.

Turn the item inside out

The inside is what has been against the skin and needs cleaning, and it is also the side that takes abrasion in the machine. Turning the item inside out means the friction hits the inner surface rather than the visible fabric, and the seams are protected. It costs nothing and makes a noticeable difference over a couple of years.

Do not wash with just anything

Zips, hook and loop fasteners and buttons pull threads out of a finely knitted fabric. Wash underwear with other underwear, or use a laundry bag. It is the same principle as with socks, and it matters even more here, where the fabric is often thinner.

The same rules for the rest

The top is treated exactly like the bottom, because the material is the same. See bamboo underwear for men and bamboo underpants for men, where the care instructions are listed on every item along with the fabric composition.

Wash after every wearing

Underwear belongs in the wash after every day rather than being aired on a chair. Odour develops in the damp period before the wash rather than during it, and an item that has lain crumpled for an evening has already started. That is why you need enough pairs to change daily without having to wash mid week. See also washing and care guide.