Question: how long are cooked mashed potatoes good for in the fridge?
Answer: Shelf life of potatoes Cooler temperatures, such as those afforded by a pantry or root cellar, allow them to keep longer than at room temperature. Once cooked, potatoes last up to 4 days in the refrigerator and 1 year in the freezer, though the quality of cooked mashed potatoes suffers with freezing (4, 5).