How long does cut watermelon last in the fridge? Properly stored, cut watermelon will last for 3 to 4 days in the refrigerator. Can you freeze cut watermelon? Yes, to freeze: Place in airtight containers or heavy-duty freezer bags. How long does cut watermelon last in the freezer? Properly stored, it will maintain best quality for about 10 to 12 months, but will remain safe beyond that time. The freezer time shown is for best quality only â cut-up watermelon that has been kept constantly frozen at 0Â° F will keep safe indefinitely.