How to Wash Cotton Clothes

💧

Cotton shrinks from heat and agitation — not cold water. Whites: 40–60°C. Colours: 30–40°C. Enzyme detergent is safe. Tumble dry on medium heat rather than high.

Why Cotton Behaves Differently to Wool and Silk

Cotton is a cellulose fibre (the same base as linen) — not a protein fibre like wool or silk. This matters because: enzyme detergents are completely safe on cotton (they destroy protein fibres), cotton does not felt or felt from agitation, and cotton can tolerate high wash temperatures. The main care consideration for cotton is shrinkage. Cotton fibres swell when wet and the weave tightens as water molecules form hydrogen bonds with the cellulose chains. Agitation in warm or hot water accelerates this. Most cotton garments sold pre-shrunk have already been washed at high temperature, but unsanforized (raw) cotton can shrink 5–10% in the first wash.

How to Wash Cotton

1
Check the care label — especially on new garments
A new cotton garment labelled '30°C' or 'cold wash only' has likely not been pre-shrunk, or is blended with a fibre (polyester, elastane) that requires lower temperatures. Follow the lowest-temperature instruction if mixed fibres are present.
2
Sort whites and colours separately
White cotton can be washed at 60°C for bacteria reduction and optical brightening. Coloured cotton should be washed at 30–40°C — higher temperatures fade dye faster. Washing red or dark garments with whites can cause colour transfer (see the colour run guide).
3
Wash whites at 40–60°C with enzyme detergent
White cotton handles high temperatures. 40°C handles most soil. 60°C is recommended for bed linen, towels, and underwear where bacteria and dust mites are a concern. Enzyme (biological) detergent is safe and more effective at lower temperatures than non-bio — use it.
4
Wash coloured cotton at 30–40°C
30–40°C protects dye vibrancy. Enzyme detergent works well at these temperatures. Turn dark and bright-coloured garments inside-out to reduce surface abrasion that fades colour.
5
Use a normal cycle for woven cotton
Shirts, jeans, and woven cotton garments handle a normal machine cycle. Use a gentle cycle for t-shirts, jersey cotton, and cotton with stretch (elastane) to reduce elongation and pilling from agitation.
6
Tumble dry on medium or low heat — or air dry
High dryer heat causes additional cotton shrinkage and weakens fibres over time. Medium to low heat is sufficient to dry cotton. Air drying is gentler and extends garment life. Remove from the dryer slightly damp and hang or fold immediately to reduce wrinkles.

Cotton and Shrinkage

Pre-washed (sanforized) cotton is the most common type you will encounter — it has been treated to minimise further shrinkage. New pre-washed cotton typically shrinks less than 3% after the first wash. Unsanforized (raw) cotton sold by the metre, or some artisan garments, can shrink 5–10%. If you receive a new cotton garment that seems slightly large, and the care label permits higher temperatures, the first wash at 40–60°C will allow some controlled shrinkage.

By Cotton Item

T-shirts and jersey cotton

30–40°C. Gentle cycle. Turn inside-out to reduce pilling and colour fade. Low-medium dryer heat or air dry. Iron inside-out at medium heat.

Cotton shirts (woven)

40°C normal cycle. Iron at medium-high cotton setting while slightly damp for the smoothest result. White shirts: 60°C if heavily soiled.

Jeans and denim

Cold or 30°C wash. Inside-out. Low-medium dryer. Jeans do not need frequent washing — every 5–10 wears is sufficient for most use.

White bed linen and pillowcases

60°C for bacteria and dust mite reduction. Enzyme detergent. Tumble dry medium. Iron at high heat while slightly damp for crispness.

Towels

60°C. No fabric softener — softener coats cotton fibres and reduces absorbency. Tumble dry medium to high heat, or air dry in direct sunlight.

Cotton underwear and socks

60°C for hygiene. Enzyme detergent. Tumble dry.

Cotton canvas and workwear

40–60°C. Normal heavy cycle. Air dry or medium tumble. Pre-treat stains before washing.

Ironing Cotton

•Cotton irons best while still slightly damp — either remove from the dryer slightly damp, or use a spray bottle.
•Use a high cotton setting (200–210°C) or the steam iron's cotton/linen mark.
•Steam helps significantly on dry cotton.
•Iron white cotton on the right side. Iron coloured and dark cotton on the reverse (inside) to protect the colour and sheen.

What to Avoid

Washing coloured cotton at 60°C

High temperatures accelerate dye bleeding and fading. White and light-coloured cotton handles 60°C; coloured cotton should be washed at 30–40°C to preserve colour over time.

High dryer heat on fitted cotton

High dryer heat causes cotton to shrink further and weakens the fibre structure over time. Low to medium heat — or air drying — extends garment life significantly.

Washing cotton with bleach (for coloured items)

Chlorine bleach strips dye from cotton. Use oxygen bleach (like OxiClean or Vanish Oxi) for stain removal on coloured cotton — it removes stains without removing colour.

Leaving wet cotton in a pile

Wet cotton develops mildew smell rapidly. Transfer to dryer or hang immediately after the wash cycle ends.

Washing cotton t-shirts on a hot, high-spin cycle

Jersey cotton (t-shirt fabric) distorts under high spin and hot temperatures. Gentle cycle, 30°C, and medium spin preserve shape and reduce pilling.

FAQ

What temperature should I wash cotton at?

White cotton: 40–60°C. 60°C is recommended for bed linen, towels, and underwear for bacteria reduction. Coloured cotton: 30–40°C to protect dye vibrancy. Black and dark cotton: 30°C to prevent fading. If the care label says 30°C, use 30°C — the garment may not be pre-shrunk or may be a cotton blend with a fibre that requires a lower temperature.

Does cotton shrink in the wash?

Most cotton garments sold today are pre-shrunk (sanforized) and shrink less than 3% further in washing. Unsanforized raw cotton can shrink 5–10%. Cotton shrinks from a combination of heat and agitation — cold washing minimizes further shrinkage. Tumble drying on high heat causes additional shrinkage beyond what the wash causes. If you need to avoid any further shrinkage, wash cold and air dry.

Can cotton go in the tumble dryer?

Yes. Cotton handles the tumble dryer well. Use medium or low heat rather than high heat to reduce further shrinkage and preserve fibre strength. Remove slightly damp to make ironing easier and reduce wrinkles. High heat over many cycles weakens cotton fibres and causes garments to wear out faster.

Can you use biological (enzyme) detergent on cotton?

Yes — enzyme detergent is safe and recommended for cotton. Cotton is a cellulose fibre, not a protein fibre, so the protease enzymes in biological detergent do not damage it (unlike with wool or silk). Enzyme detergent is more effective at removing protein stains (blood, sweat, food) from cotton than non-biological detergent, particularly at lower temperatures.

Got a cotton stain?

Use the stain picker →