Power Outage Food Safety: The 4-Hour and 48-Hour Rules (USDA)
The USDA says a refrigerator keeps food safe for about 4 hours if the door stays closed. A full freezer holds its temperature for about 48 hours (about 24 hours if half full) (USDA FSIS; also FoodSafety.gov).
Timeline
| Time without power | What to do |
|---|---|
| 0 hours | Keep fridge and freezer doors closed. Put an appliance thermometer in each if you have one. |
| Up to ~4 hours | Fridge food generally still safe if the door stayed closed. |
| After ~4 hours | Discard perishable food (meat, poultry, fish, eggs, leftovers, milk) that has been above 40 °F for 2 hours or more, per USDA. |
| 24–48 hours | A half-full or full freezer may still be holding. Food with ice crystals or at 40 °F or below can be refrozen. |
When in doubt, throw it out. Never taste food to decide whether it is safe.
Prepare before the next outage
- Keep appliance thermometers in the fridge (40 °F or below) and freezer (0 °F or below).
- Freeze containers of water. They help keep the freezer cold and give you drinking water later.
- Know where you can get ice or dry ice locally.
Can a battery power station keep the fridge running?
Often yes, for a while. A typical modern fridge uses roughly 1–2 kWh a day, but the real number depends on your model and how often the door opens. Check the EnergyGuide label and do the math with the Watt Weekender calculator (our sister site). A ~2 kWh station such as the BLUETTI Elite 200 V2 (affiliate link) or the ALLPOWERS R2500 V2 class (affiliate link) may cover about a day of fridge use on paper. Your actual runtime will vary.