How long do potatoes last

Keep raw potatoes unwashed, in a bag with holes or an open basket, somewhere cool, dark, and dry. FoodKeeper prints the pantry window as 1–2 months and the fridge as 1–2 weeks. The FSA says you can choose the fridge or a cool, dark, dry place if you want to waste less. Starch turning to sugar in the cold is an older quality note; the study the FSA cites found that a home fridge does not materially raise acrylamide-forming sugars compared with a cool dark place. Light grows the green colour and the glycoalkaloids. The FSA says remove the sprouts, and cut off green or rotten bits before you use the potato. Green, damaged, and sprouted parts can carry higher glycoalkaloids; a high level can cause abdominal pain, vomiting, and diarrhoea, and poisoning is rare.

Boiled, roasted, or mashed potato is a leftover. The FSA says eat leftovers within two days or freeze them, 2 days. FoodKeeper prints a side dish such as vegetables, rice, or potatoes at 3–4 days. The large figure is two days. The side-dish freezer line is 1–2 months. FoodKeeper prints a separate freezer line for cooked and mashed potatoes: 10–12 months. That is longer than the side-dish line; mash sits on the long line, and a plain boil sits on the side-dish line. A raw whole potato has no freezer cell: Cooked or mashed, not raw. The FSA says you can freeze potatoes that have been boiled for five minutes, parboiled potatoes, and leftover cooked potatoes. If a frozen one goes into the oven, cook it until it is steaming hot all the way through.

Get perishable food into the fridge within 2 hours of cooking it or bringing it home, and within 1 hour if the kitchen is above 32°C (90°F). USDA FSIS and Turkey’s Ministry of Agriculture and Forestry both publish that cutoff. A closed deep pot stays warm; a shallow box cools.

A chart is a window, not a verdict on the container in your hand. A sour smell, a slimy surface, or mould means it is finished, even on day one. This page is not medical advice.

• Soft, watery flesh, or a sour smell.
• Black rot that has spread inside. Cutting around a small bruise is one thing; rot across half the tuber is another.
• Green across most of the skin. The FSA says cut off the green bit; if the tuber has turned green, leave the whole thing.
• On cooked potato, a sour smell or a sticky, slimy surface.

Do not freeze a raw whole potato. The FSA describes freezing cooked potatoes, potatoes boiled for five minutes, and leftovers. The window for a boil or a roast is the side-dish line, 1–2 months. Mash is 10–12 months. Portion them, press the air out, and thaw in the fridge. Do not refreeze what thawed. A frozen boiled potato can go into the oven with a little oil until it is steaming hot.

Thaw in the refrigerator, not on the counter. Do not refreeze a portion that has thawed. The ministry states the same rule: thaw frozen food in the fridge and take out only what you will eat.

• The fridge poisons a potato. The FSA lists a home fridge as a choice next to a cool dark place, and reports that acrylamide-forming sugars do not rise in a material way. FoodKeeper’s quality window is shorter in the fridge: 1–2 weeks, against 1–2 months in the pantry.
• A sprout finishes the potato. The FSA says cut the sprout off and use it. Cut off green or rotten bits too. If the tuber is green all over, leave the whole thing.
• Cooked potatoes keep for a week. The FSA closes leftovers at two days, 2 days. FoodKeeper prints the side dish at 3–4 days.

The windows assume a generally healthy household. Pregnancy, young children, older age, or a weakened immune system are reasons to keep the shorter figure, to skip raw or undercooked food, and to reheat leftovers until the centre is steaming. USDA’s figure for reheating leftovers is 74°C (165°F).

Green, sprouted, and bruised parts carry glycoalkaloids. For a young child, in pregnancy, and with a weakened immune system, do not try to save a green tuber by cutting; leave it. If a cooked leftover is past two days, or it sat warm, heating does not bring the safety back. Raw potato on this page is not eaten uncooked.