Food Safety After a Power Outage, What to Keep and What to Toss
A closed refrigerator keeps food safe for about 4 hours without power, and a full freezer for about 48 hours. After that, or once food has been above 40°F for more than 2 hours, the USDA Food Safety and Inspection Service (FSIS) and FoodSafety.gov say to sort it item by item with a keep-or-toss chart. The limits below are from their pages as of October 2026.
1. The two numbers to remember
FSIS says to keep refrigerated food at or below 40°F and frozen food at or below 0°F. When the power fails, the clock starts on both:
| Appliance | How long it holds safe temperatures, door closed |
|---|---|
| Refrigerator | About 4 hours |
| Full freezer | About 48 hours |
| Half-full freezer | About 24 hours |
The single most useful thing you can do during an outage is keep the doors shut. Every opening lets cold air out and shortens those windows.
If the outage will run long, FSIS suggests getting dry ice or block ice. Its benchmark: 50 pounds of dry ice should hold an 18-cubic-foot full freezer for 2 days. Knowing ahead of time where to buy ice in your area saves a frantic search.
2. Set up before the next outage
A few steps from FSIS make the after-outage decisions much easier:
- Keep appliance thermometers in both the refrigerator and the freezer at all times. FSIS notes that when the power is out, an appliance thermometer still shows the temperature inside no matter how long the outage lasts.
- Group frozen items together. When a freezer is not full, keeping items close together helps them stay cold longer.
- Have coolers and frozen gel packs on hand. FSIS calls coolers a great help if power will be out for more than 4 hours.
- Stock shelf-stable food, including canned goods, boxed or canned milk, water, ready-to-use baby formula if needed, pet food, and a hand-held can opener.
One more FSIS point that comes up every winter: do not put food outside in the snow. Sun can thaw frozen food even when it is very cold, outdoor temperatures swing hour by hour, and animals can get into it. FSIS suggests a better use of the cold: fill buckets or empty milk cartons with water, let them freeze outside, and put that ice in your fridge, freezer, or cooler.
3. After the power comes back: the refrigerator
FoodSafety.gov says to discard refrigerated perishable food such as meat, poultry, fish, eggs, and leftovers after 4 hours without power. Its chart covers food exposed to 40°F or above for more than 2 hours. Evaluate each item separately, and FSIS is emphatic about one thing: never taste food to decide whether it is safe. Appearance and smell are not reliable either.
A sample of the chart:
| Food | At 40°F or above for over 2 hours |
|---|---|
| Raw or cooked meat, poultry, seafood; lunchmeats, hot dogs | Discard |
| Milk, cream, yogurt, soft cheeses, shredded cheese | Discard |
| Hard cheeses (cheddar, Swiss, Parmesan), processed cheese | Keep |
| Fresh eggs, egg dishes, custards | Discard |
| Butter, margarine | Keep |
| Cooked pasta, rice, potatoes; casseroles, soups, stews | Discard |
| Bread, rolls, cakes, muffins, tortillas | Keep |
| Fresh fruit, cut; fresh vegetables, cut | Discard |
| Fresh fruit and vegetables, uncut | Keep |
| Peanut butter, jelly, mustard, ketchup, pickles, soy sauce | Keep |
| Opened creamy dressings, opened spaghetti sauce | Discard |
| Opened vinegar-based dressings | Keep |
| Opened mayonnaise, tartar sauce, horseradish | Discard if above 50°F for over 8 hours |
Go item by item rather than by rule of thumb. The full chart has surprises: soy, Worcestershire, and barbecue sauces are keeps, but fish sauce and oyster sauce are on the discard list, as are refrigerator biscuit and cookie dough.
4. After the power comes back: the freezer
Here the deciding test is simple. FSIS says food that still contains ice crystals or is at 40°F or below can be safely refrozen. If you kept an appliance thermometer in the freezer and it reads 40°F or below when power returns, FSIS says the food is safe and may be refrozen.
Without a thermometer, check each package. FoodSafety.gov's frozen-food chart shows meat, poultry, seafood, and stews or soups that still contain ice crystals can be refrozen, while the same foods exposed to 40°F or above for more than 2 hours should be discarded. Ice cream and frozen yogurt are on the discard list either way.
Partial thawing and refreezing may reduce the quality of some foods, FSIS notes, but the food remains safe to eat. FSIS also says to throw out anything in either appliance that has come into contact with raw meat juices during the thaw.
5. A quick walk-through when the lights come on
- Read the fridge and freezer thermometers before opening anything else.
- If the fridge was without power for more than 4 hours, or perishable food was above 40°F for 2 hours, pull out the foods on the discard list.
- In the freezer, keep and refreeze packages with ice crystals or at 40°F or below.
- Throw out anything that touched raw meat juices.
- When in doubt, follow FoodSafety.gov's own line: throw it out.
6. Key takeaways
- A closed refrigerator keeps food safe for about 4 hours; a full freezer about 48 hours, a half-full one about 24.
- Keep appliance thermometers in both units so you know the real temperature after an outage.
- Discard perishable refrigerated food after 4 hours without power or more than 2 hours above 40°F; hard cheeses, butter, bread, and most condiments are usually fine.
- Frozen food with ice crystals or at 40°F or below can be refrozen.
- Never taste food to test it, and toss anything that touched raw meat juices.