Does Cotton Shrink in the Wash? How to Prevent It

Why does cotton shrink?

During manufacturing the cotton yarn is stretched. When the garment meets heat and moisture, the fibres relax and pull back toward their natural, shorter length – this is called relaxation shrinkage. Most of it happens in the dryer on high heat, not in the wash itself. If the fabric is pre-washed (often labelled 'pre-shrunk' or sanforised) it has already been through this and shrinks little. Untreated cotton, like some cheap tees and raw denim, can shrink a few percent the first time.

How to keep cotton from shrinking

If you want to keep the fit, it is all about keeping the heat down – both in the water and in drying.

1. Wash cold to lukewarm (30 or lower) on a normal or gentle cycle.
2. Skip the hot dryer, which is the biggest cause of shrinkage. Air dry, or tumble on low heat.
3. Take the garment out while it is still slightly damp and shape it back to fit.
4. Do not overload the drum, so the garment moves less and is treated gently.

Bleach: oxygen, not chlorine

For grey or dull white cotton, bleach is tempting, but choose the right type. Chlorine bleach weakens the cotton fibre over time, can yellow it and create holes.

• Use oxygen bleach (sodium percarbonate) on white cotton – it is gentler and safe on most garments.
• Chlorine should only be used on pure white 100% cotton if the label allows it, sparingly and well diluted, with a thorough rinse afterwards.
• Detergent with optical brighteners freshens up greyed whites without chemical bleaching.
• Never use chlorine on coloured cotton – it eats the colour away in patches.

Stop coloured and dark cotton from fading

Coloured cotton fades from friction, hot water, too much detergent and sunlight. A little care keeps blacks black and colours fresh for longer.

1. Turn garments inside out and wash dark and strong colours together, separate from lights.
2. Wash cold with a mild detergent, and do not over-dose – residue wears on the colour.
3. Air dry inside out and out of direct sun, which bleaches.
4. Wash less often: air garments out between wears instead of washing every time.

Can you rescue a shrunken cotton garment?

A little, but not always. Soak the garment in lukewarm water with a splash of hair conditioner or baby shampoo for about half an hour, squeeze out the worst of the water without wringing, and gently stretch it back to shape while it is damp. Lay it flat to dry. This recovers some of the relaxation shrinkage, but the harder shrinkage that happens once the fibre structure itself has set is largely permanent.

When should you leave it to professionals?

If the cotton garment is expensive, tailored or important to you – a shirt, a suit, a coat – or you are unsure whether it can be washed at home, you can send it to us. We clean according to the garment and its care label, so the shape and colour are looked after. If a white piece has gone grey or yellowed, or it also needs a repair, we can assess it at the same time. You order online, and you see the price before you order.

Frequently asked questions