How to Wash Cotton: Temperature, Drying and Stains

Step by step

1
Check the care label
Read the wash temperature, bleach and drying symbols. Most cotton can be machine washed, but the label sets the limits; laundry symbols explains each one.

Why: The care label states a safe method for that specific garment, including any finish or trim that can't take heat.
2
Sort by color and soil
Separate whites, pastels and mediums, and darks and brights. Keep heavily soiled work clothes or towels apart from lightly worn shirts. Wash new dark or bright cotton on its own the first few times.

Why: Dark cotton can release dye, and dirt from heavily soiled items can resettle on lighter ones and turn them gray.
3
Pick the water temperature
Wash whites and heavily soiled cotton in the hottest water the label allows with the recommended dose of detergent. Wash colored cotton in warm or cold water.

Why: Hot water removes body soil and keeps whites from yellowing. Cool water limits fading, which matters because natural fibers fade more readily than synthetics.
4
Use the right bleach, if any
Use chlorine bleach only on white or colorfast cotton whose label shows an empty triangle, added to the wash, never poured on dry fabric. Use oxygen bleach for colored cotton.

Why: Chlorine bleach strips dye from cotton that isn't colorfast, and it can yellow or weaken wrinkle-resistant (durable-press) finishes.
5
Dry on normal or medium, and don't overdry
Tumble dry on a normal or medium setting. Take cotton knits like T-shirts out while they're still slightly damp, reshape them, and lay them flat to finish drying.

Why: The American Cleaning Institute names overdrying as the main cause of shrinkage, and once cotton has shrunk, it doesn't come back.
6
Iron while slightly damp
If needed, iron cotton on the high setting (three dots, up to about 200°C or 390°F), ideally while it's still a little damp.

Why: Cotton tolerates the highest iron setting, and moisture helps relax the wrinkles that cotton forms easily.

What cotton is, and what that means for washing

Cotton is a plant fiber made of cellulose. It's strong and absorbent, which is why it handles machine washing and hot water well. The same structure explains its weak points. It wrinkles easily, can mildew if left damp, is weakened by long exposure to sunlight, and shrinks unless the manufacturer pre-treated it.

Chemistry matters too. Cotton tolerates alkaline detergents and, on whites, chlorine bleach, but acids weaken it. Georgia extension warns that full-strength vinegar or lemon juice can permanently damage cotton, so dilute them with at least 2 parts water to 1 part acid. Some shrinkage in knits and wovens is normal, ACI notes, so allow for it when buying, and expect pre-shrunk cotton to shrink less.

Getting stains out of cotton

Cotton's tolerance for heat and bleach makes it one of the easier fabrics to clean, but heat still has to wait until the right step:

Grease and oil: blot, rub in heavy-duty liquid detergent or dish soap, and wash in the hottest water safe for the item. Check before drying, since dryer heat bakes oil in. See grease on clothes.
Blood: rinse from the back with cold water, soak in cold water with an enzyme detergent, then wash warm. Hot water first cooks the protein in. See blood on clothes.
Tomato sauce: scrape off the excess, rinse cool, pretreat with liquid detergent, then wash and use oxygen bleach, or chlorine on white cotton, for the red color. See tomato sauce on clothes.
Chocolate: it's a combination of fat, protein and color. Scrape, rinse in cold water, pretreat with detergent, wash, then bleach any brown that remains. See chocolate on clothes.

Air-dry and check after any stain treatment. On cotton, you can repeat a treatment safely; once it has been through a hot dryer, the stain is much harder to move.

By situation

White cotton shirts and sheets

Use hot water and, if the label allows, chlorine bleach added to the wash. If whites keep going gray or yellow, increase the detergent dose and the water temperature within the label's limits.

Colored and dark cotton

Use cold or warm water, wash inside out with like colors, and use oxygen bleach rather than chlorine. Keep dryer time short to reduce fading.

Cotton T-shirts and knits

Knits shrink the most. Wash warm or cold, dry on medium, and take them out while slightly damp to finish flat.

Cotton blends

Blends such as cotton-polyester can't always take the hottest water or iron setting that pure cotton can. Follow the label's temperature, dryer and iron settings rather than treating them as pure cotton.

Wrinkle-resistant (durable-press) cotton

Use the permanent-press cycle, which has a cool-down rinse, and avoid chlorine bleach, which can yellow or weaken the resin finish.

What not to do

Don't overdry cotton knits. Overdrying is the main cause of shrinkage, and it can't be reversed.
Don't use full-strength vinegar or lemon juice on cotton. Acids can permanently weaken cotton fibers; dilute them first.
Don't wash new dark or bright cotton with lights. Excess dye bleeds out in the first washes.
Don't use chlorine bleach on colored cotton unless a test shows it's colorfast. It removes dye from cotton that isn't colorfast, leaving permanent light spots.

Other methods that work

Line-drying

Hanging cotton to dry avoids dryer shrinkage entirely, and it's the gentlest option for knits you want to keep the same size.

Caution: Long exposure to strong sunlight weakens cotton and can fade colors, so dry colored cotton in the shade.

Hand washing

For delicate cotton like lace or vintage pieces, hand wash in warm or cool water with mild detergent, squeeze rather than wring, and dry flat.

Caution: Follow the label: some cotton items have trims or finishes that need special care.

Stain still there?

My cotton shirt shrank

Overdrying is the usual cause. Some residual shrinkage is normal, but it can't be reversed. Next time, dry on medium and remove it while slightly damp.

White cotton looks gray

Rewash with more detergent, hotter water and a bleach safe for the fabric, and sort heavily soiled items into their own loads.

Cotton smells musty after washing

It stayed damp too long. Rewash hot with a fabric-safe bleach and dry it right away; see the steps for smelly towels.

Questions

What temperature should cotton be washed at?

The hottest the label allows for whites and heavily soiled items, and warm or cold for colors. Hot cleans better; cooler water limits fading.

Does cotton shrink in the wash or the dryer?

Mostly in the dryer. ACI identifies overdrying as the main cause, especially for knits.

Can you bleach cotton?

White or colorfast cotton labeled bleach-safe can take chlorine bleach, added to the wash water. Colored cotton should get oxygen bleach.

How do you get grease stains out of cotton?

Rub heavy-duty liquid detergent or dish soap into the spot, then wash in the hottest water safe for the fabric. Check it before drying and repeat if needed.

Can you get blood out of cotton?

Yes. Rinse it with cold water, soak with an enzyme detergent, and wash warm. Avoid hot water and the dryer until the stain is gone.

More laundry guides

Sources

Fiber Types, University of Georgia Cooperative Extension (Textiles)
Laundering Problems and Solutions, American Cleaning Institute
Laundry Basics, American Cleaning Institute
Using Bleach in the Laundry, American Cleaning Institute
Guide to apparel and textile care symbols, Office of Consumer Affairs, ISED Canada
Products (textile care products), University of Georgia Cooperative Extension
Stain Removal for Washable Fabrics (HE 2-840), University of Kentucky Cooperative Extension Service
Stain Removal Guide, American Cleaning Institute

Last updated October 26, 2026. Methods are drawn from the sources above; how we research and check our guides.