No, it is not considered safe to eat pizza that sat out at room temperature overnight. Food safety guidelines say perishable foods like pizza should not stay in the “danger zone” (about 40°F–140°F / 4°C–60°C) for more than about 2 hours because bacteria can multiply quickly.
Food safety rule
Pizza with cheese, meat, or other perishable toppings counts as a perishable food, even though it was baked. After a couple of hours at room temperature, bacteria that can cause foodborne illness may reach unsafe levels, even if the pizza still looks and smells fine.
Why reheating is not enough
Reheating pizza that has been left out overnight does not reliably make it safe again. Some bacteria can leave toxins behind that are not destroyed by normal reheating, so you can still get sick.
What to do instead
- If pizza has been out at room temperature longer than about 2 hours (or 1 hour in very hot conditions), the safest option is to throw it away.
- In the future, refrigerate leftover pizza within 2 hours and eat it within a few days, or freeze it for longer storage.
