A boiled egg can stay out of the refrigerator for up to 2 hours. After that time, it should be refrigerated or reheated before serving. A cooked or boiled egg can remain in the refrigerator for up to a week.
When serving either cold or hot egg dishes at a buffet, it is a wise to keep them either cold or hot to avoid problems associated with food poisoning. However, it is important to serve eggs as soon as possible after cooking them. Egg dishes or casseroles should be cooked thoroughly such that a cooking thermometer inserted into the dish reads 160 degrees Fahrenheit.
Taking these precautions with eggs can prevent food poisoning associated with the salmonella bacteria. Similarly, raw eggs should be stored in the refrigerator after bring them home from the store. It also is important to use eggs within 3 weeks after storing them in the refrigerator.