When you first receive a Purple mattress, it typically takes around 24 to 48 hours for it to fully expand and reach its intended shape. Upon unboxing, the mattress may appear compressed and rolled, but it begins to regain its original form shortly after being removed from the packaging. During the initial hours, you may notice noticeable expansion, yet for optimal comfort, it is advisable to allow the mattress to fully expand for about 48 hours. Additionally, factors such as room temperature can influence the expansion time. Warmer environments tend to facilitate quicker expansion, while cooler conditions might prolong the process. It is always a good idea to check the latest information on the Purple website for any specific guidelines regarding the expansion and setup of their mattresses.