My Down Comforter Smells Like Mildew

A mildew smell develops as the result of mildew spores being present on the surface. If your down comforter has become musty smelling, similar to a damp basement, then you're likely to have mildew growing on the comforter. This tiny living organism grows on surfaces that are moist and in environments that are warm. While removing the mildew and odor from your down comforter, take care to avoid damaging the comforter itself.

Things You'll Need

  • Bowl

  • Lemon juice

  • Table salt

  • Old toothbrush

  • Mild laundry detergent

  • 1 cup white vinegar

  • Tennis balls

Step 1

Mix lemon juice and table salt in a bowl to create a thin paste. Brush the lemon paste onto any mildew stains on your down comforter. Lay the comforter in the sun and allow the lemon paste to dry.

Step 2

Brush the dried lemon juice paste off your down comforter.

Step 3

Wash your down comforter in a large capacity washing machine. Use warm water and laundry detergent. Add 1 cup white vinegar to the wash cycle to kill any remaining mildew spores and deodorize the smelly comforter.

Step 4

Place your clean down comforter into the dryer with a few clean tennis balls. Run the dryer on a full cycle to dry the comforter. The tennis balls keeps the down from lumping up inside the comforter.


Lay your comforter outside and spritz it with diluted vinegar. Let the comforter dry in the sun. Vinegar kills the mildew and deodorizes your comforter.

Sprinkle baking soda over a musty smelling down comforter. Leave the baking soda on the fabric to absorb the smell overnight. Shake out or vacuum off the comforter the next day.


Washing your down comforter once each month or so will not damage the comforter and will help prevent mildew development and odor.

References & Resources