That yellow patch under the arms of a white shirt usually comes from sweat and antiperspirant building up together. The fix starts at the kitchen sink. Rub undiluted liquid dish detergent into the stain, let it sit, and wash the shirt in the warmest water its care label allows. For older stains, University of Georgia Extension suggests a few drops of white vinegar first. A soak in oxygen bleach helps on whites. Keep the shirt away from the iron and the dryer until the stain is gone.
Key Takeaways:
- Most underarm stains are a mix of sweat and antiperspirant residue, and they build up over time.
- Undiluted dish liquid, rubbed in and left to sit, is the first thing to try on any washable shirt.
- White vinegar helps on old stains, and an oxygen bleach soak brightens whites.
- Heat from an iron or dryer can set a sweat stain, so air dry until it’s gone.
- Never mix chlorine bleach with ammonia or vinegar.
Why do sweat stains turn yellow?
Underarm stains build up when sweat mixes with antiperspirant and body oils and soaks into the same spot of fabric, day after day. UGA Extension notes that deodorants and antiperspirants containing aluminum chloride are acidic and can change the color of some dyes. On a white shirt, that chemical reaction looks yellow. On a dark shirt it can look like a faded or chalky patch.
The longer residue sits, the harder it is to get stains out of clothing. A wash that doesn’t clear the residue leaves a little more behind each time, and UGA warns against ironing or applying heat to a deodorant stain at all.
Silk and rayon are especially sensitive to perspiration, so a stained silk blouse or rayon dress should go to a professional cleaner, as should anything labeled dry clean only.
How to get yellow sweat stains out of white shirts
Here’s how to remove sweat stains from a shirt, starting with the gentlest step. These steps are for washable cotton and poly-cotton shirts. Check the care label first, and test each product on an inside seam.
- Dab a few drops of white vinegar on an old yellow stain, or a few drops of household ammonia on a fresh one, to help restore the color.
- Rinse the spot with plain water before the next step.
- Rub undiluted dish soap into the stain on both sides of the fabric and let it sit for about 30 minutes.
- Soak the shirt for 15 to 30 minutes in warm water with an oxygen bleach, such as sodium perborate.
- Wash the shirt in the hottest water its care label allows.
- Check the underarms before drying, and repeat the soak if you can still see the stain.
- On stubborn stains on white fabric, apply 3% hydrogen peroxide for 15 to 20 minutes, then wash again, and expect it to take two or three rounds.
- Air dry the shirt until the stain is fully gone.
The soak and hot-water steps come from UGA Extension’s perspiration stain guide, which also suggests soaking a shirt overnight in warm salt water, about three or four tablespoons of salt per quart, if the smell lingers after washing.
A word on safety. Never mix chlorine bleach with ammonia or with vinegar, and rinse the fabric between products. Don’t combine hydrogen peroxide and vinegar in the same container either, since together they form a corrosive acid. UGA also cautions that ammonia damages silk and wool.
A paste of baking soda and water is a common home remedy too, though UGA’s guide doesn’t list it. Skip lemon juice on colored shirts, since it can lighten dyes. If you’re deciding which whitening product to keep on hand, our guide to laundry whitener vs bleach walks through the difference.
How to get armpit stains out of black shirts
Dark shirts show a different kind of stain, usually a white or gray film of deodorant or a patch where the dye has shifted. Skip bleach and hydrogen peroxide here, since both can lighten dark dyes.
Turn the shirt inside out and rub a little undiluted dish liquid into the underarms. Let it sit, then rinse with cold water. If the patch looks faded or reddish, UGA suggests a few drops of white vinegar on old stains to help bring the color back. Wash the shirt inside out on the temperature its label calls for, and hang it to dry.
To keep the white marks from coming back, let deodorant dry completely before you pull a dark shirt over your head.
How OrangeBag handles stained shirts
When you book a pickup, the order has room to note stains or special care instructions, so flag the underarms or collar. Shirts are $7.95 each by the piece, and everyday laundry goes by the bag at $2.65 per pound, returned sorted and folded in 24 to 48 hours. OrangeBag’s wash and fold and dry cleaning prices cover every item and fee. For dry-clean-only shirts that pick up a spill before pickup day, here’s what’s safe to try on dry-clean-only fabric.
We pick up across Los Angeles, and the page on laundry pickup and delivery in Los Angeles shows how it works.
Sweat stain FAQ
Can sweat stains be removed?
Most can. Knowing how to get sweat stains out mostly comes down to timing. Fresh stains usually lift with dish liquid and a warm wash. Older yellow stains take more work, like vinegar, an oxygen bleach soak, and sometimes a few rounds of hydrogen peroxide on white fabric. Stains that have been washed and dried many times can leave a permanent tint, and some fabrics weaken where the stain sat.
Does vinegar remove sweat stains?
Vinegar helps, but it rarely finishes the job alone. UGA Extension suggests a few drops of white vinegar on old sweat and deodorant stains to help restore color that’s shifted. Follow it with a rinse, undiluted dish liquid, and a wash. Dilute vinegar on cotton and linen, and never combine it with chlorine bleach.
How do you get neck sweat stains out of dress shirts?
A collar ring is mostly body oil and sweat. Rub undiluted liquid detergent into the ring, work it in gently with a soft brush or your thumb, and let it sit before washing. Wash in the warmest water the label allows. If the shirt goes to a cleaner, mention the collar so it gets treated before pressing.
How do you keep sweat stains from coming back?
Wash shirts soon after you wear them, since removing stains gets harder the longer residue sits. Let antiperspirant dry before dressing, and use a little less of it. Treat the underarms with dish liquid every few washes on shirts you wear often. Keep stained shirts away from heat until the marks are completely gone.
Tired of scrubbing underarms at the sink?
Flag the stains when you book and let us handle the washing. A driver picks up at your door and brings your shirts back clean.
