How to Wash and Care for Denim

Denim is unusual among fabrics in that the standard laundry advice makes it worse. A pair of jeans washed the way you wash a tee will fade unevenly, lose its shape at the knees and seat, and wear out at the stress points years earlier than it needed to.

The reason is that most of the damage denim takes happens in the machine, not on the body. Agitation abrades the fabric, hot water shrinks and weakens the cotton fibres, and detergent slowly strips the indigo. Wearing jeans barely damages them at all by comparison.

How often should you actually wash jeans?

Far less often than you probably do. For ordinary use — office, commute, everyday errands — every ten wears or so is reasonable. Some people go considerably longer. Wash immediately if they are visibly dirty, if you have spilled something, or if you have been sweating heavily in them; otherwise the clock is much slower than for other garments.

In between, air them. Hanging jeans somewhere with moving air overnight removes most of the smell, because the odour is bacterial and bacteria need moisture. A few hours in fresh air does most of what a wash would do, without any of the wear.

How to wash them when you do

• Turn them inside out. This is the single most effective step — it puts the abrasion on the inside face and protects the visible indigo surface.
• Cold water, always. Hot water shrinks cotton, sets creases and accelerates fading. Cold is not a compromise here; it genuinely cleans denim adequately.
• Gentle or delicate cycle, and a short one. Less agitation, less wear.
• Mild detergent, and not much of it. Skip anything containing bleach or optical brighteners, which attack indigo directly.
• Wash with similar colours, and wash new dark denim separately the first couple of times — it will bleed.
• Fasten the button and zip before washing so they do not snag the fabric.

Never put them in a hot dryer

Machine drying on heat is what destroys denim fastest. It shrinks the cotton, damages any elastane in stretch denim so the jeans go permanently baggy, and abrades the surface. Line dry instead — hang by the waistband or fold over a line — and take them down while very slightly damp.

Dry them out of direct sunlight. Strong sun bleaches indigo, and it does it unevenly across whichever face is pointing at it.

Stretching, sagging and shrinking

Jeans that feel loose after a day of wear have not stretched permanently in most cases — cotton relaxes as it warms and takes up moisture from your body, and a wash brings much of it back. This is why buying jeans that feel slightly snug in the shop is usually right, and why buying jeans that already feel comfortably loose leaves you with jeans that sag by afternoon.

Stretch denim behaves differently. The elastane recovers between wears if you let it, which is another argument for rotating between two pairs rather than wearing the same one daily. Once elastane has been heat-damaged in a dryer, though, that recovery is gone for good.

Fading, and how to control it

Raw and dark denim fades where it creases and rubs — behind the knees, at the hips, at the pocket edges. Many people want that; it is what makes a pair look personal. If you do, wash rarely and always inside out, and the fade develops naturally along the lines your body makes.

If you would rather keep the colour even and dark, wash inside out in cold water with a detergent made for dark colours, dry away from the sun, and avoid sitting for long stretches on light-coloured upholstery in brand-new dark denim, which transfers dye.

Spot cleaning and small repairs

For a single spill, sponge the area with cold water and a little mild detergent rather than washing the whole garment. Blot rather than rub — rubbing pushes the stain into the weave and lifts the surface dye.

Watch the inner thigh, where most jeans eventually wear through. The moment you see the weave thinning there, get it reinforced by a tailor. Patched before it opens, it is invisible and the jeans last another couple of years; patched after it opens, it always shows.

The freezer myth

You may have read that putting jeans in the freezer sanitises them. It does not. Freezing makes bacteria dormant rather than killing them, and they revive as soon as the jeans warm up. Airing works; freezing is theatre.

The honest summary is short: wear them a lot, wash them rarely, cold and inside out, and never tumble dry. Denim treated that way lasts for years and looks better every one of them.