Casper offers a 100-night trial for all mattresses. The trial begins on the day of delivery and is 40% shorter than the average trial length (165 nights). During this period, you can test your new mattress and decide whether to keep it or return it.

If you send back the mattress, Casper will recycle it or give it to charity and refund your money. All you need to do is contact customer service to arrange a pickup. Both shipping and returns are free.
Note that every retailer has a different return policy. The above conditions apply if you order your mattress directly from Casper.
Your new mattress also comes with a 10-year limited warranty, so you can still return it after the trial ends. However, the warranty only applies under certain conditions.