And how to tell if your sleeping companion is past its prime.

Over time, dead skin cells, sweat and oil you produce over night make their way into your pillow — which is why it’s so important to wash it every six months. After all, you rest your head on it every single night. If you’re the proud owner of a feather pillow, use this advice from the Good Housekeeping Institute Cleaning Lab to revive it and help make it last longer.

How to wash feather pillows

Good news: You can toss these pillows in your washer. We recommend using a front- or top-loading machine without an agitator — a.k.a. the large spindle found in the middle of some machines, designed to help rotate water and clothes. If an agitator-style top loader is your only option, place the pillows in the tub vertically, so it’s less likely they’ll get wrapped around and damaged by the agitator.

Another thing to look out for before washing: If there are any slits or tears in the pillow cover. For balance, load two pillows at a time and use only a small amount of detergent. We recommend Good Housekeeping Seal holder Gain Liquid Detergent ($43 for a 2-pack, Set the machine on the delicate cycle and give the pillows a second rinse.

How to dry

Place your pillows in the machine. “In the Good Housekeeping Institute, we toss in a few rubber dryerballs, like Nellie’s ($14 for a 2-pack,, to help plump the filling and keep it from clumping as it dries,” says Carolyn Forte, director of the Good Housekeeping Institute Cleaning Lab. It’s also a good idea to take the pillows out periodically and fluff by hand, using your fingers to break up any clumps. Pillows will take longer to dry than a normal load of clothes. If they have a musty smell, set them in the sun for a couple of hours.

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