Costco cheesecake can last 5 to 7 days in the fridge if stored properly. Be sure to keep it in its original packaging or an airtight container to maintain its freshness. If you don’t plan to eat it within that time frame, you can also freeze it, and it should last for up to 6 months in the freezer. When you’re ready to enjoy it, just thaw it in the fridge for several hours or overnight.