Yes, leftover puff pastry sausage rolls can be reheated. Remove sausage rolls from the refrigerator and place into a preheated 350° F. oven or air fryer and reheat just until heated through, about 10 to 15 minutes. Please note that reheated sausage rolls may not be as crispy as when they were freshly baked, but they will still be delicious. Reheating them in a microwave can make the pastry soggy so the oven or air fryer is a better option.