Be careful with feather pillows. If the label says don't do it, or your pillow is really old, now is not the time to be a rebel. The pillow will explode in your washing machine and you'll be stuck cleaning feathers for the foreseeable future.

Angie's How To Clean Your Pillows
So maybe you toss your sheets in the wash every week or so, and we're guessing your mattress gets flipped about once a year, but when is the last time you cleaned your pillows? It's tempting to skip this step, but pillows become bacteria havens if they're left to their own devices. Keep them germ- and bacteria-free by cleaning them twice a year.
3 pros!
Toss two pillows in the washing machine at a time. This way, the machine will stay balanced while it spins. Use mild liquid detergent rather than powder detergent – powder will leave residue on your pillows.
Run your pillows through the rinse cycle twice to make sure that the detergent is completely removed from the pillow. Soap isn't a good bedfellow.
When you throw your pillows in the dryer, add in 2-3 tennis balls wrapped in white socks. They'll help to refluff your pillows!
If you can't get your pillows clean, it might be time for a new pillow. To find out of you need a new pillow, try this pillow test.