Mattress company Sleep Number filed for bankruptcy on Friday and plans to sell its assets under a $415 million buyout offer from a Canadian bedding company.

While evergreen sales can mean great savings on a new mattress anytime of year, mattress companies tend to offer their biggest discounts during a few key sales events—and Black Friday is one of them.

Add Yahoo as a preferred source to see more of our stories on Google. Even though it's the one piece of furniture on which you'll spend the most time throughout your life, how to shop for a mattress ...

Editor's note: This article is part of a series on sustainability. You can find the whole package at our landing page. Mattress retailers face complicated operational problems when it comes to returns ...