Why Does Water Temperature Matter When Washing White and Colorful Laundry?

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Make no mistake about it: The correct water temperature is crucial to your laundry. "Water temperature determines the strength of the cleaning process, and selecting the appropriate water temperature for a particular fabric is essential to minimizing damage over time," Gwen Whiting, the co-founder of The Laundress, explains. "The correct water temperature ensures a more effective cleaning and can reduce the chance of color bleeding, warping, or damage to the fabric." While most fabrics composed of densely woven fibers (like cotton and linen) can typically be washed in warm water without the risk of shrinking or fading, lifestyle and laundry expert Cheryl Nelson, the founder of Prepare with Cher, says that it's smartest to use cool water when in doubt. "Not only can cold water minimize the chance of damage, but it requires less energy, so it's great for the environment and saving money," she explains.

Interested in learning more about why we wash white items in warm water and brightly colored fabrics in cold? Laundry experts share their insight ahead.

Warmer water leaves whites brighter, but proceed with caution.

While the common trope is to wash all white clothing in hot water, this isn't always the best course of action. Unfortunately, certain fibers can shrink and weaken in hot (above 130 degrees Fahrenheit) water, but won't get a deep, thorough cleaning in anything considered too cold (between 60 to 80 degrees). The trick? "Wash white linens in lukewarm water, which generally falls between 90 to 110 degrees," Nelson explains. Lindsey Boyd, co-founder of The Laundress, affirms this, adding that warm water is typically recommended because it can effectively lift the accumulation of dirt, body oils, and stains while minimizing the risk of shrinkage. "Both hot and warm water may cause certain fabrics to fade or shrink," she notes. "However, hot water shrinks items to their maximum shrinkage capacity after one wash, whereas warm water will shrink them more gradually over multiple washes."

To ensure your white clothes get a deep, thorough clean in warm water, Nelson recommends washing them on the gentle cycle of your washing machine with similarly hued fabrics. "Don't wash them with colorful fabrics or else the colors may bleed," she warns. "And don't put too many items in the washing machine, as this can cause the fabric to twist or pull."

We wash bright fabrics in cool water to prevent color transfer.

Since colorful fabrics are made with dyes that can fade, bleed, or transfer in hot and warm water, Whiting says bright and dark-hued items (as well as ones composed of delicate fabrics such as cashmere, silk, or wool) should always be washed in cold water (go warmer, and dye transfer becomes more likely). "If you have stains on colorful fabric, you can pretreat the item as you would with white linens," she explains. To give these garments a deep cleaning, Nelson recommends washing them on the gentle cycle with as much cold water as possible so they can move around freely in the machine. "To keep the longevity of your vibrant colors, it also helps to turn your bright linens inside out before washing," she adds.

When in doubt, use cool water.

To avoid accidentally washing your beloved garments and bedding in the incorrect temperature, Whiting recommends setting your washing machine to use the cold water cycle for all loads. "This will minimize the risk of fabric damage," she explains. And if a white garment sneaks into a load of brights or vice versa, don't fret, says Boyd. "If you notice some dye transfer, you can soak the white linens in a basin or sink of hot water with two capfuls of a bleach alternative and wash as normal with hot water," she says.