Most people don’t realize how differently we treat our pajamas until the topic comes up in conversation. Mention that you wash yours once a week, and someone will insist they wash theirs after every single night. Others proudly rotate the same pair for days without a second thought. The truth is, pajama-washing habits vary widely because our bodies, routines, and comfort levels are all different. But beneath those personal preferences lies a simple question worth asking: how often should we really wash the clothes we sleep in?

Dermatologists say the answer depends largely on sweat, skin oils, and nightly habits. If you tend to sweat at night, live in a warm climate, or skip the shower before bed, your pajamas accumulate bacteria more quickly and need to be washed more often. Conversely, people who shower before bed or sleep in cooler temperatures can safely stretch a few nights between washes. The fabric matters too—cotton tends to absorb oils and odors faster than synthetics, while certain materials can irritate sensitive skin if not cleaned regularly. Overwashing can wear down fibers; underwashing can irritate your skin, trigger breakouts, or worsen allergies.

Experts generally recommend washing pajamas every three to four wears, but that guideline shifts based on lifestyle and environment. Some cultures emphasize daily washing for hygienic or symbolic reasons, while others take a more relaxed approach. Regardless of where your preferences fall, it’s worth remembering the environmental impact: unnecessary laundry wastes water, energy, and detergent. Washing in cold water, running full loads, and using gentle detergents can help maintain both your pajamas and the planet.

The best routine is ultimately one that balances comfort, cleanliness, and practicality. Ask yourself how fresh your pajamas feel after a few nights, whether your skin reacts to extended wear, and how your nighttime habits affect your hygiene. Rotating multiple pairs, airing pajamas between uses, and treating stains promptly can all help keep them in better shape. There may not be a universal rule, but listening to your body—and your laundry basket—will guide you to a rhythm that keeps both you and your pajamas feeling clean and comfortable.