Since these bars have a cream cheese frosting on top, I recommend storing them in the fridge. Since the bar itself is made with oil rather than butter, they won't become stiff rocks either. You can also allow them to sit at room temperature for 20ish minutes until the bar has warmed up prior to eating it if you would like. The bars will last about 5 days in the fridge as long as they're stored in an airtight container.