The core rule
USDA guidance: an unopened refrigerator keeps food safely cold for about 4 hours. Keep the door closed and the clock honest. Once power returns — or once you can check with a thermometer — the question is whether perishables spent more than 2 hours above 40 °F (4 °C).
What to discard after 4+ hours without power
Discard perishables: raw and cooked meat, poultry, fish, eggs, milk, soft cheeses, cut fruit and vegetables, cooked leftovers, opened sauces with dairy, and deli foods. This holds regardless of how the food looks or smells — the hazards involved are undetectable by inspection.
What generally survives
Hard cheeses, butter, most whole raw fruits and vegetables, bread, condiments high in acid or sugar (ketchup, jam, soy sauce), and unopened shelf-stable items that were refrigerated only for preference. When in doubt about an item, check it in the Power-Outage tool — item by item, never wholesale.
Prepare before the next one
- Keep an appliance thermometer in the refrigerator so you can read the actual temperature afterward.
- Keep ice packs or frozen water bottles to extend the safe window in a long outage.
- Never taste food to test it.