How long does food last in the fridge without power? Food safety in a power outage
How long food lasts in a fridge or freezer without power, what you can refreeze, what to throw out, and food rules after a flood. Based on USDA and CDC.
Without power, a fridge keeps food cold for about 4 hours, a full freezer for about 48 hours and a half-full freezer for about 24 hours. There is one condition: keep the doors closed. Below you will find what to do in the first hour of an outage, what you can eat or refreeze, and what has to go. The last section covers floods, where the rule is short and strict.
The first hour without power
- Note the time the power went out. That is your starting point for the 4 hours (fridge) and 24 to 48 hours (freezer).
- Keep the fridge and freezer closed. Every opening shortens the time your food stays safe.
- Group frozen food together. Items packed tightly stay cold longer than items spread across drawers.
- Plan your meals. Eat the perishable food from the fridge first. Save frozen food and shelf-stable tins for later.
- Use winter cold with care. A balcony or porch only helps when it is genuinely cold all day and night. Sun during the day can warm food faster than a switched-off fridge.
If the outage looks long, see our blackout preparedness guide for light, heat, water and power.
Fridge without power: what to keep, what to throw out
The line is 4°C (40°F). Many perishable foods that have been above that temperature for more than 2 hours must be thrown out. If power came back within 4 hours and the door stayed shut, the food is usually fine.
| Food | Above 4°C (40°F) for more than 2 hours |
|---|---|
| Raw or cooked meat, poultry, fish, deli meats | Throw out |
| Milk, yoghurt, soft cheese, cream | Throw out |
| Eggs and egg dishes | Throw out |
| Leftovers, cooked pasta and rice, cut fruit and vegetables | Throw out |
| Opened mayonnaise, tartar sauce, horseradish | Throw out if above 10°C (50°F) for more than 8 hours |
| Hard cheese, butter, whole raw fruit and vegetables, bread | Usually safe to keep |
| Opened ketchup, mustard, jams and jellies | Usually safe to keep |
An inexpensive appliance thermometer in the fridge and freezer removes the guesswork. Without one, count the time from the moment the power went out.
Freezer without power: when you can refreeze
Frozen food that still has ice crystals or is at 4°C (40°F) or below can go back in the freezer. It may lose some taste and texture, but it is safe. If it has fully thawed and stayed warmer than that for more than 2 hours, throw it out.
Thawed vegetables and vegetable juices are a little more forgiving: throw them out if they have been above 4°C (40°F) for more than 6 hours.
If the power is not coming back and meat is thawing but still cold, you can cook it straight away on a gas hob or a camping stove. Without a fridge, eat it at once, within 2 hours at most.
How to prepare your fridge and freezer for an outage
- Keep bottles of water in the freezer. They fill empty space, hold the cold longer and give you drinking water once they thaw.
- Keep the freezer full. A full freezer stays cold about twice as long as a half-full one.
- Ice packs and a cool bag let you move the most important items, such as medicines that need refrigeration.
- Stock food that needs no fridge: tins, UHT milk, crackers. Details are in our emergency water and food supply guide.
Food after a flood: no exceptions
The rule from the CDC and USDA is simple: throw out any food that may have come into contact with flood water. Flood water can carry sewage, chemicals and other contamination. The USDA flood sheet says to discard all such food, including canned goods, home-canned jars and anything in paper, cardboard, cloth or plastic packaging.
- Drink, wash produce and cook only with bottled water, or tap water that local authorities have confirmed is safe. If you are told to boil or treat water, follow the official instructions.
- Throw out wooden cutting boards, plastic utensils, baby bottle teats and dummies (pacifiers) that were in flood water. Wash metal pans, ceramic dishes and metal cutlery in hot soapy water, then sanitise them.
- Clean and sanitise the fridge, cupboards and worktops that held flooded food before you put new food there.
- If you get diarrhoea, vomiting or a fever after a flood, contact a doctor quickly.
For a household plan that covers floods and evacuation, see the family emergency plan.
Remember in 10 seconds
- Fridge: 4 hours. Full freezer: 48 hours, half-full: 24 hours.
- The safety line is 4°C (40°F) and 2 hours.
- Ice crystals mean you can refreeze.
- Contact with flood water means throw it out.
- When in doubt, throw it out. Food poisoning during a crisis, when clinics are overloaded, costs far more than a few items of food.
FAQ
How long does food last in the fridge without power?
About 4 hours if the door stays closed. After that, meat, poultry, fish, deli meats, dairy, eggs and leftovers that have been above 4°C (40°F) for more than 2 hours should be thrown out.
How long does a freezer stay cold without power?
A full freezer holds a safe temperature for about 48 hours and a half-full one for about 24 hours, as long as you keep the door closed.
Can I refreeze food that has thawed?
Yes, if it still has ice crystals or is at 4°C (40°F) or below. Taste and texture may suffer, but it is safe. If it has been warmer than 4°C (40°F) for more than 2 hours, throw it out.
Can food that touched flood water be saved?
No. Throw out any food that may have come into contact with flood water. Drink and cook only with bottled water, or tap water that local authorities have confirmed is safe.
How can I tell if food has gone bad?
Often you cannot. Bacteria that cause food poisoning usually do not change how food smells or looks. Go by time and temperature, never by taste or smell. When in doubt, throw it out.
Sources
This guide is educational. In an emergency, follow official alerts and first responders.