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. Daily fridge energy use depends on your model and how often the door opens, so check its 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 be able to run many fridges for a meaningful part of a day; do the math for your own fridge. Your actual runtime will vary.