White t-shirts and how to make them white again

Short answer: White t-shirts turn white again when you remove what makes them yellow-grey: sweat, deodorant residue, detergent and limescale. Wash them separately, use enough water and an oxygen-based stain remover, and let them dry in the shade. Here is how to do it step by step.

Why white t-shirts turn yellow and grey

White t-shirts pick up dirt faster because everything shows on light fabric. Sweat and deodorant settle in the fibres, limescale adds a film, and washing with coloured clothes can give a greyish tone. It is rarely the fabric itself that has broken down, but build-up on it.

Wash white t-shirts on their own

Keep white t-shirts apart from colours and dark clothes so they do not pick up dye. That goes especially for new clothes, which can release colour. If you choose bamboo, check the care label in your bamboo T-shirts for men and wash at the recommended temperature.

Oxygen-based stain remover instead of chlorine

An oxygen-based stain remover is gentler than chlorine and works well on sweat and yellow marks. Soak the clothes in lukewarm water with the remover, follow the dose on the pack and leave them for a few hours. Chlorine can leave yellow rings on some fabrics, so only use it if the care label allows it.

Pre-treat underarms and collar

Underarms and collar are where white t-shirts first show discolouration. Rub a little bar of soap or a paste of water and bicarbonate of soda into the area and leave it for half an hour. Rinse, then wash as normal, and most build-up will come out.

Enough water and not too much detergent

If you cram the drum, the laundry has no room to rinse properly. Fill it two thirds at most, and use the amount of detergent stated on the pack. Too much detergent leaves residue that makes white t-shirts grey and stiff, especially in hard water.

Drying and sunlight

Sunlight can brighten white laundry a little, but it can also turn some fabrics yellow. Dry white t-shirts in the shade if the fabric yellows in the sun, and hang them up as soon as the wash is done. Damp laundry lying together can get a smell and marks.

Stop white t-shirts from turning yellow again

Change the t-shirt when it is sweaty, and wash it without leaving it in the basket for days. Let deodorant dry before you get dressed. Choose a deodorant without aluminium if you keep seeing yellow marks, and talk to a doctor about any skin problems.

White t-shirts in everyday life

If you have several white t-shirts, rotate them so they do not wear quickly. White t-shirts go with almost everything and also work as a layer under other clothes, together with socks for men and bamboo boxer briefs, which are just as easy to wash with whites.

Frequently asked questions

How do I get yellow underarms out of a white t-shirt?

Pre-treat with soap or a paste of bicarbonate of soda and water, let it work, then wash. If that is not enough, soak the clothes in an oxygen-based stain remover, and always check the care label first.

Can you use chlorine on white t-shirts?

Only if the care label allows it. Chlorine can leave yellow rings and weaken some fabrics, so an oxygen-based stain remover is usually the gentler and safer choice for whites.

Why do white t-shirts turn grey in the wash?

Usually because of build-up from detergent, limescale or dye from other clothes. Wash whites separately, do not use too much detergent, and leave the drum room to rinse properly.

You can find the full range at Copenhagen Bamboo.