For most people, experts recommend washing bed sheets about once a week. A weekly wash removes the sweat, oils, allergens, and dust that naturally collect during sleep. Some situations call for more frequent cleaning. Wash every three to four days if you sweat heavily, sleep with pets, eat in bed, have allergies or asthma, deal with a skin condition such as eczema, or are recovering from an illness. Once a week is usually enough if you shower before bed, sleep alone, keep pets off the mattress, and maintain a relatively clean bedroom.

Sheets are only part of the equation. Pillowcases should be washed every three to seven days, especially if you have oily skin or allergies. Blankets need cleaning every two to four weeks. Comforters and duvets protected by a cover can often go two to three months between washes, while the duvet covers themselves should be cleaned every one to two weeks. Washable pillows benefit from a thorough cleaning every four to six months, and mattress protectors should be washed every one to two months or sooner after spills.