How Long Do Leftovers Really Last and What Can You Do To Extend the Shelf Life?

Whether you have take-out or home-cooked meals, leftovers last about 3-5 days in the fridge. Previously hot or cold perishable foods left at room temperature will also only last for about 1-2 hours before needing refrigerating.¹

If you don’t store your leftovers properly or leave your leftovers in the fridge for too long, bacteria will begin growing on your food and cause it to spoil. This can increase your risk of foodborne illnesses like food poisoning.¹

Factors That Affect the Shelf Life of Leftovers

How long your leftovers last depends heavily on temperature and time. Bacteria grow quickly in temperatures between 40 degrees Fahrenheit (°F), or 4 degrees Celcius (°C), and 140 °F (60 °C). Once leftovers enter this temperature range, bacteria can double every 20 minutes and spoil food. It only takes about two hours for unrefrigerated leftovers to spoil.²  

In warmer temperatures over 90 °F (32 °C), bacteria can grow faster and spoil leftovers in an hour.²   

Storing leftovers in the fridge helps keep food at 40 °F (4 °C) and below range and slows harmful bacteria growth. However, even if you promptly refrigerate leftovers, bacteria will still start to grow on food and become unsafe after about 3-4 days.¹

Freezing leftovers at or below 0 °F (-17 °C) halts bacteria growth that causes spoilage.³ Still, the quality and taste of the food will deteriorate after about 3-4 months.⁴

What Is the Best Way To Cook?

How To Store Leftovers Safely

Here are some basic guidelines for how long you can leave leftovers out:¹  

• Hot foods: Refrigerate leftovers two hours after cooking or removing from a warming appliance (like a slow cooker or other warmer)
• Cold perishable foods: Refrigerate foods like poultry, meat, fish, and dairy products within two hours
• Hot temperatures: Refrigerate leftovers within one hour if you’re outside in the heat or have food in a hot car

Divide large quantities into multiple shallow containers when storing leftovers in the fridge or freezer. This will help the food cool down to safe temperatures more quickly. This method is particularly essential for foods like soup and whole roasts of meat, which take a long time to cool. For example, a large roast may still be warm in the center after two hours of refrigeration, allowing bacteria to grow, while smaller portions of meat will have cooled by then, slowing bacteria growth.¹ 

Avoid storing leftovers in a crowded fridge, which decreases air circulation needed for proper cooling.⁵

Cover your leftovers with airtight lids, plastic wrap, or other reusable covers. You can also wrap cold perishable foods in sealed packaging, such as plastic wrap or vacuum-sealed bags. Keeping leftovers covered and sealed helps prevent more bacteria from getting into your food. It also helps your food retain moisture and avoid absorbing odors from other foods that can alter the taste of your leftovers.¹⁵  

Freezing vs. Refrigerating 

If you’re not planning on eating leftovers in 3-5 days, you can freeze them to increase their shelf life to 3-4 months. (Leftovers containing mayonnaise, cream sauces, and lettuce don’t freeze well or taste very good once defrosted).³ 

Frozen leftovers can technically last indefinitely, but freezing removes moisture from food, altering taste and quality over time. This is why frozen leftovers often lose tenderness, flavor, color, and juiciness.³ 

For best results, freeze leftovers immediately so they’re already at their peak quality and flavor. When you’re ready to eat frozen leftovers, thaw them in the refrigerator, cold water, or microwave. You must also eat thawed leftovers within 3-4 days, as defrosted foods will start to grow bacteria.³ 

Signs of Spoiled Leftovers

Spoiled food is usually noticeable because it changes in appearance, odor, and taste. Common signs your leftovers have spoiled include:⁶⁵

• Darkening or fading color⁷
• Texture changes that feel sticky, tacky, or slimy⁸
• Fuzzy green, white, or black mold⁹
• Foul smell or taste

What To Do if You Eat Something Spoiled

Eating spoiled leftovers introduces harmful bacteria to the digestive tract that can lead to foodborne illness, also known as food poisoning. As a result, you may experience symptoms like diarrhea, vomiting, abdominal pain, fever, and headache.¹⁰

Food poisoning symptoms can happen suddenly, 6-24 hours, or days after eating spoiled food. The bacteria Staphylococcus aureus, Salmonella enteritidis, E. coli, Campylobacter, and Clostridium perfringens are common culprits of leftover-related food poisoning. These bacteria thrive in foods left in unsafe temperatures between 40-140 °F (4-60 °C).²¹¹ 

If you accidentally eat spoiled leftovers, don’t panic. Most cases of food poisoning last for less than 24 hours or a few days. You can also typically manage food poisoning symptoms at home without needing medical intervention or experiencing complications.¹¹¹⁰

How To Treat Food Poisoning

If you get food poisoning from bad leftovers, you can typically treat symptoms at home by resting and replenishing any fluids and electrolytes you lose from diarrhea or vomiting. If you don’t hydrate, you risk dehydration. Adults can also take over-the-counter (OTC) medicines like Imodium (loperamide) or Pepto-Bismol (bismuth subsalicylate) to help treat diarrhea.¹²

Liquids and foods that can help replace fluids and electrolytes include:¹²

• Water
• Fruit juices diluted with water
• Sports drinks
• Oral rehydration solutions like Pedialyte, Naturalyte, Infalyte, and CeraLyte (especially for children or older adults)
• Electrolyte drinks or powders added to water
• Broths
• Saltine crackers

See your healthcare provider if your symptoms do not resolve after a few days or worsen. Bloody diarrhea and fever are also signs of an infection that needs medical treatment. Healthcare providers may need to treat more severe food poisoning with antibiotics and rehydration solutions.¹² 

How To Extend the Shelf Life of Leftovers

To help your leftovers last as long as possible, here are some additional food safety tips to keep your food fresh:⁴¹³

• Freeze or refrigerate as soon as possible: Store leftovers in the fridge or freezer within 1-2 hours of eating. Throw out any foods left out longer than two hours or in temperatures above 90 °F (32 °C) after one hour.
• Keep food in sealed containers: Always store leftovers with a lid or wrap that keeps them sealed from bacteria and other fridge odors.  
• Divide up large quantities: Store previously hot leftovers in small amounts and shallow containers, which helps them cool quickly.
• Test your fridge temperature: Use an appliance thermometer to ensure your fridge is set to 40 °F (4 °C) or below and your freezer is 0 °F (-17 °C) or below.  
• Use a food storage app: The FoodKeeper app (developed by the USDA’s Food Safety and Inspection Service) provides precise tips for different leftovers. 
• Keep hot foods hot: If you’re leaving hot food out for more than two hours, keep cooked foods in a slow cooker, chafing dish, or warming tray to keep them hot.
• Keep cold perishable foods cold: If you leave cold perishable foods like deli meats and potato salad out for more than two hours, put them on ice. 
• Avoid fridge contamination: Clean your fridge regularly and store leftovers away from raw meat to avoid spreading more bacteria and other pathogens.
• Reheat hot leftovers: Microwave or cook leftovers in the oven to 165 °F (74 °C) or above.

A Quick Review

Leftovers can last in the fridge for about 3-5 days before spoiling. You can freeze leftovers for about 3-4 months before food quality and taste diminish. Previously hot food or cold perishable foods left out at room temperature should be refrigerated within two hours. If you’re having an outdoor picnic or event in temperatures over 90° F (32 °C), food needs to be refrigerated within an hour to stay fresh.

Leftovers with a foul smell or a change in appearance or texture are likely spoiled and should be thrown out.