The CDC recommends leftovers be refrigerated at 40°F or colder as soon as possible and within two hours of preparation to prevent food poisoning. Cut up the turkey or big portions of beef for refrigeration so they will cool quickly. Also, all leftovers should be reheated to at least 165°F before serving.
And if you don't think you can polish off those leftovers in a couple of days, you should freeze them. Stored in a refrigerator, leftovers can stay good for three to four days, Lisa Yakas, a senior project manager at NSF International, told USA Today. But if stored in a freezer, it's three to four months.
It's best to label the food with an expiration date when it's put away, to help keep track of when it's no longer safe to eat, Yakas said.