How long can leftovers sit out?
Under current US federal guidance, perishable food should generally not be left unrefrigerated for more than 2 hours. Above 90°F / 32°C, the limit is 1 hour.
Official sources checked September 13, 2026 Based on official US food-safety guidance Independent site
The 2-hour rule for perishable food
Cooked leftovers, takeout and other perishable foods should go into the refrigerator within 2 hours. If the air temperature is above 90°F / 32°C, use the shorter 1-hour limit. Food that has gone beyond the applicable limit should be discarded.
Putting food into the refrigerator later does not undo an exposure that already exceeded the applicable time limit. An overnight period out of refrigeration is beyond both limits.
What the guidance says
The FDA tells consumers not to leave perishable foods out at room temperature for more than 2 hours, unless hot foods are being kept hot and cold foods are being kept cold. When eating outdoors in temperatures above 90°F, perishable food should not be left out for more than 1 hour. It also says to bring leftovers home and refrigerate or freeze them within 2 hours.
USDA’s leftovers guidance is just as direct: throw away perishable foods that have been left at room temperature for more than 2 hours, or 1 hour if the temperature is over 90°F.
When does the clock start?
In practice, the clock runs while the food is not being held at a safe temperature. For hot food, that means from the moment it is no longer being kept hot. For cold food, it means from when it leaves the refrigerator or cooler. USDA’s food-dating guidance gives a picnic example: cold chicken salad left out at temperatures above 40°F for more than 2 hours should not be eaten.
Picnics and buffets can be different
Food being actively held cold at 40°F / 4°C or below, or hot at 140°F / 60°C or above, is a different situation from food simply sitting out. If safe holding was not maintained, the normal time-and-temperature limits still matter. For serving situations, read our picnic and buffet food safety guide.
Worked examples
Dinner finishes at 7:00pm on an ordinary evening, and the leftovers are still on the counter. The 2-hour limit means they need to be in the refrigerator by 9:00pm.
A cookout at midday reaches 95°F. The temperature is above 90°F, so the 1-hour limit applies, and perishable food should be put away by 1:00pm.
A pizza arrives at 7:00pm and is found on the counter at 11:00pm. That is 4 hours, beyond both limits, and the guidance is to discard it.
Getting leftovers cold quickly
USDA advises dividing large amounts of food into shallow containers so it cools quickly. The FDA advises using a refrigerator thermometer to make sure the refrigerator is at 40°F or below, and the freezer at 0°F or below.
Use the details you know
The checker asks for the actual duration and whether the temperature was above 90°F / 32°C. It can also route a refrigerated item that came back out of the fridge, or food served at a picnic, party or buffet, to the appropriate supported check.
Common questions
Can I eat leftovers that sat out for 3 hours if I reheat them?
The guidance is to throw away perishable food left out beyond the limit, and it does not make an exception for reheating.
Does the rule apply to every food?
It applies to perishable foods. Shelf-stable foods follow the storage instructions on their packaging.
What if I do not know how long it was out?
The checker needs a known duration, and it will tell you that it cannot confirm the answer if it does not have one.
What about food that was refrigerated and brought back out?
The checker has a separate supported route for that. Start with the checker and choose the situation that matches.
Next steps
Once leftovers are safely in the refrigerator, see how long leftovers last in the fridge for the 3 to 4 day window. You can also read USDA’s leftovers and food safety guidance
Looking for UK guidance? Read our UK cooked chicken left out guide.
Use the checker for your situation
This page explains general US federal guidance. Check your food using the relevant supported situation.
Sources and scope
Last checked: September 13, 2026.
This resource is based on United States federal guidance for the situations described. It does not replace the checker’s questions or food-specific storage instructions.
Safe to Eat? is independent and is not affiliated with or endorsed by the authorities cited above.