How to Store Leftovers Safely: The 2-Hour and 4-Day Rules
The danger zone, the 2-hour rule, how to cool big batches quickly, how long leftovers keep, and how to reheat and thaw them safely, based on USDA guidance.
The Danger Zone: 40°F to 140°F
Bacteria that cause food poisoning, such as Salmonella, Clostridium perfringens, Staphylococcus aureus, and Bacillus cereus, grow fastest between 40°F and 140°F (4°C and 60°C). In that range their numbers can double in as little as 20 minutes.
Food safety comes down to keeping food out of that range as much as possible: hot food hot, cold food cold, and moving quickly between the two.
The 2-Hour Rule
Refrigerate or freeze cooked food within 2 hours of cooking, or within 1 hour if it's been sitting somewhere above 90°F (32°C), like a picnic or a hot car.
Don't wait for food to cool on the counter before putting it in the fridge. Modern refrigerators can handle warm food, and it's safer than leaving it out.
Cool Big Batches Fast
A large pot of soup or chili can stay warm in the center for hours, even in the fridge. Help it cool quickly:
- Divide it into shallow containers, no more than about 2 inches (5 cm) deep.
- Cut large roasts into smaller pieces.
- Stir soups and sauces in a sink of ice water for a few minutes before refrigerating.
- Leave containers loosely covered until cold, then seal them.
How Long Leftovers Keep
In a fridge at 40°F (4°C) or colder:
- Most cooked leftovers (meat, poultry, casseroles, soups, stews): 3-4 days
- Cooked rice and pasta: 3-5 days
- Pizza: 3-4 days
- Hard-boiled eggs: 1 week
- In the freezer at 0°F (-18°C), food stays safe indefinitely, but for best quality eat most leftovers within 2-6 months.
Reheating Safely
Reheat leftovers until they reach 165°F (74°C) throughout, steaming hot in the center. Bring sauces, soups, and gravies to a rolling boil.
In a microwave, cover the food, stir halfway through, and let it stand for a minute or two, because microwaves heat unevenly. Slow cookers aren't recommended for reheating leftovers; they warm food too slowly.
It's best to reheat only the portion you'll eat. Food can safely be reheated more than once if it's handled properly, but quality drops each time.
Thawing Frozen Leftovers
Thaw in the fridge overnight, in cold water, or in the microwave. Leftovers thawed in the fridge can be refrozen if you don't use them. Those thawed in cold water or the microwave should be reheated right away. You can also reheat many frozen leftovers straight from the freezer; they just take longer.
Don't Rely on the Smell Test
The bacteria that make food go "off" (smelly, slimy, moldy) aren't the same ones that make you sick. Food can look and smell fine and still be unsafe, especially past the 3-4 day mark. When in doubt, throw it out.
Common questions
Can I put hot food straight in the fridge?
Yes. It's safer than leaving it out. For a very large pot, split it into smaller containers first so it cools quickly.