How Long Can a Fridge Go Without Power?

Severe weather, like monsoons, floods, and heat waves, can cause power outages. When the power goes out, the electricity powering your fridge and keeping your food cool is at risk.

A brief lapse in power, one lasting a few minutes, won't affect the food quality in your refrigerator or freezer. However, what about electrical outages that last hours or days?

Generally, if you keep the doors shut, food stays good in the fridge without power for four hours. Also, food stays good for 24 hours in a half-full freezer and 48 hours in a completely-full freezer.

Here's everything you need to know about how long your refrigerator stays cold after losing power—including when bacteria growth becomes a threat and forces you to toss perishable food.

How Long Can a Fridge Go Without Power?

Without power, a fridge will likely remain at a safe temperature for up to four hours if the door is kept closed. Food in your freezer stays cold for even longer, lasting for about a day if the freezer is half-full or nearly 48 hours if it's full. If there's more food inside the freezer, it retains the cold temperature longer than if there is less food.

Still, don't be tempted to check on your food every few minutes. Opening the fridge or freezer accelerates the temperature increase. So, your food spoils quicker than if you keep the doors shut.

When To Toss Your Food

During a power outage, you can use the appliance thermometers inside your fridge and freezer to determine if your food is safe.

Your fridge temperature should be 40 degrees Fahrenheit or lower. In contrast, the freezer should be zero degrees Fahrenheit or lower. If there's no thermometer inside the appliance to gauge the temperature, use a food thermometer on each item to see if it's safe to eat.

Some foods, like dairy products and meats, might look or smell bad. Still, you can't always rely on your senses to determine food safety. If you're unsure whether to toss your food, the Food Safety and Inspection Service (FSIS) provides a quick guide on when to discard various food groups.

For example, if it's been above 40 degrees Fahrenheit for more than two hours, immediately discard foods like:

• Lunch meat
• Soft cheese
• Milk
• Yogurt

On the other hand, you can keep hard cheese, butter, margarine, uncut fresh fruit, and breakfast foods, like waffles and pancakes.

Always err on the side of caution. So, if you're questioning the safety of your food during a power outage—or anytime, for that matter—it's better to rely on shelf-stable pantry items for your meals.

However, to avoid food waste, eat perishable items—including leftovers, meat, milk, soft cheese, or cream—first, assuming their temperatures guarantee their safety.

Prevent Foodborne Illness

You shouldn't taste perishable foods to see if they're spoiled. Any refrigerated food that sits above 40 degrees Fahrenheit for more than four hours is prone to collecting bacteria. Bacteria increase the risk of foodborne illness. Instead, checking the temperature of your food will ultimately tell you if it's safe to eat.

Symptoms of foodborne illness, which typically occur one to three days after eating contaminated food, include:

• Vomiting
• Diarrhea
• Body aches and pains, mainly near the abdomen
• Fever
• Headache

People with foodborne illnesses usually recover shortly after. If you have severe symptoms, like dehydration, consult a healthcare provider right away.

Move Your Food to Dry or Block Ice

If it's likely that your power will be out for several days, purchase dry or block ice for your fridge or freezer. The ice will maintain the temperature of any perishable items.

Move refrigerated foods to the ice if it's been over four hours during a power outage. Ensure that refrigerated and frozen food stays at 40 and zero degrees Fahrenheit or less, respectively. Then, you can reheat or cook frozen food during a power outage.

However, don't put your food outside to keep it cold, even during winter. Outside temperatures may be cold enough for refrigerated food but too warm for frozen food. So, even if it's very cold outside, the sun could still heat your food to a temperature that cultivates bacteria.

Plan Ahead To Freeze Your Food

Preparing for possible power outages lessens the health impacts of not having access to food. According to one study published in 2018 in the Journal of Urban Health, among New York residents, only 56% of young adults were prepared for a power outage.

In addition to keeping non-perishable food, you can take steps to maximize the lifespan of your refrigerated and frozen foods. Those steps may include the following:

• Using freezing gel packs to 40 degrees Fahrenheit or less to cool perishable refrigerated foods
• Obtaining a cooler and dry or block ice to store those foods if the power outage lasts longer than four hours.
• Grouping frozen foods in a protective "igloo," keeping meats together on one side of the freezer or on a tray

Remember to keep frozen meat away from other foods. So, if they start to thaw, their juices that may harbor bacteria won't mix with other foods.

A Quick Review

If your power goes out, refrigerated food will stay good for four hours. Frozen food will stay good for one day in a half-full freezer and two days in a completely-full freezer. 

Ensure you do not eat food above 40 degrees Fahrenheit for longer than four hours. During that time, the food is at a high risk of entering the "danger zone," where it collects bacteria. Bacteria increase your risk of foodborne illness.