Shirts that still smell of sweat: how to wash out underarm odour

Quick answer: sweat odour lingers because sweat and deodorant residue build up in the fibres, especially in synthetic fabrics and sportswear. To get rid of it: wash soon after wearing, pre-treat the underarms with detergent, soak for 15–30 minutes, wash in cool or moderately warm water and dry completely where there is airflow.

Why do clothes still smell after washing?

• Left too long before washing: a sweaty shirt sitting in the basket all day lets the smell sink in.
• Synthetic fabrics and sportswear hold odours longer than cotton.
• Deodorant residue builds up in the underarm area and is hard to remove with a normal wash.
• Slow drying: fabric that stays damp for hours picks up a musty smell on top of old sweat.
• Overloaded machine: detergent can’t reach everything.

Step-by-step fix

1. Turn the shirt inside out so the underarms get more contact with detergent.
2. Pour a little detergent directly onto the underarms and rub gently or brush with a soft brush.
3. Soak for 15–30 minutes in cool water with detergent.
4. Wash in cool or moderately warm water as the care label allows. Very hot water can set sweat stains.
5. Don’t overload the drum.
6. Hang immediately, where there is airflow, and only put away when fully dry.

Sportswear and uniforms worn all day

For clothes worn all day and gym wear, use a detergent with odour control. For example, SPY Deep Clean Plus is a 2-in-1 detergent with Tinosan HP100 to help remove odours and Noverite to soften fibres, at 50–70ml per 5–7kg load.

Odours between washes

Jackets, blazers and uniforms not washed daily can be refreshed with fabric spray between washes. SPY Fabric Spray is sprayed on dry fabric from about 20–30cm away. Fabric spray is an in-between step and doesn’t replace washing.

Yellow underarm stains on white shirts

Yellow stains come from sweat and deodorant building up over time. See How to whiten yellowed white shirts at home.

Read more: Clothes smell musty after drying indoors in humid weather