How Long Do Onions Last?
Whole onions last 1–2 months in a cool, dry, ventilated pantry. Cut or chopped onion lasts 7–10 days in the fridge, cooked onions 3–4 days, and chopped raw onion freezes for 3–6 months.
Onions — whole
shelf life- Cut: 7–10 days in the fridge
- Cooked: 3–4 days in the fridge
Fridge at 40°F (4°C) or below · freezer at 0°F (−18°C). Freezer times are for best quality; frozen food stays safe longer.
Onions are cured after harvest so their outer layers dry into a papery skin, which lets whole bulbs keep for weeks at room temperature. They need dry, moving air; humidity makes them sprout, soften and mold. Sweet varieties such as Vidalia hold more water and less sulfur, so they spoil noticeably sooner than yellow storage onions.
How to store onions
- Keep whole onions in a mesh bag, basket or open bowl in a cool, dark, dry spot with airflow. Never store them in a sealed plastic bag.
- Store onions away from potatoes. The moisture potatoes give off makes onions soften and sprout, and onions make potatoes sprout too.
- Seal cut onion in a glass or hard plastic container in the fridge so the smell does not spread into butter, milk and other foods.
- Freeze chopped onion flat in a freezer bag so you can break off what you need. It goes straight into the pan for cooking, with no thawing.
- Buy sweet onions in small amounts and refrigerate them wrapped in paper towels; they do not have the keeping power of yellow onions.
How to tell if onions have gone bad
- Soft, mushy or wet spots, especially a squishy neck or base, or liquid leaking from the bulb.
- Dark, slimy layers inside when you cut the onion open.
- A rotten, sour smell that is different from a normal sharp onion odor.
- Cut onion that has turned slimy or grown mold in its container.
Bacteria that cause food poisoning usually do not change the look, smell or taste of food. Go by the time limits first, and the signs above second.
Onions shelf life chart
| State | Fridge | Freezer | Pantry |
|---|---|---|---|
| Whole | Not recommended | Not recommended | 1–2 months |
| Sweet onions are the exception: they keep better wrapped individually in the fridge, about 1 month. | |||
| Cut | 7–10 days | 3–6 months | Not safe |
| Halved, sliced or chopped, in a sealed container. No blanching needed to freeze. | |||
| Cooked | 3–4 days | 2–3 months | Not safe |
| Includes caramelized onions. | |||
Not safe = perishable: no more than 2 hours at room temperature (1 hour above 90°F / 32°C). Not recommended = possible, but quality suffers or it serves no purpose.
Frequently asked questions
Is the black powder under onion skin mold, and can I still eat it?
Yes, it is a common mold called Aspergillus niger, and the onion is usually still usable. If the black, sooty powder is only on the dry outer skin and the first layer, peel those layers off, rinse the onion and use it if it is firm. Discard the onion if it is soft or the mold reaches the inner flesh. People with mold allergies or weak immune systems should discard it.
Can you eat an onion that has sprouted?
Yes, a sprouted onion is safe to eat, and so is the green shoot. The bulb has spent some of its sugars growing the sprout, so it may be a little softer and more bitter. Cut out the sprout if you like, and discard the onion if it has also gone mushy or moldy.
Is it dangerous to store a cut onion in the fridge overnight?
No. The claim that cut onions become poisonous or absorb bacteria overnight is a myth. A cut onion kept in a sealed container at 40°F (4°C) or colder is good for 7–10 days. Like any cut produce, it should not sit at room temperature for more than 2 hours.
Should whole onions be refrigerated?
Generally no. Regular yellow, red and white onions absorb moisture in the fridge and turn soft and moldy sooner than in a dry pantry. The exceptions are sweet onions, peeled onions and anything already cut, all of which keep better refrigerated.
Related foods
| Food | Fridge | Freezer | Pantry |
|---|---|---|---|
| Garlic Whole |
Not recommended | Not recommended | 3–5 months |
| Green Onions Whole |
7–10 days | 3–4 months | Not recommended |
| Leeks Whole |
1–2 weeks | 3–6 months | Not recommended |
| Potatoes Raw |
Not recommended | Not recommended | 1–2 months |
| Bell Peppers Whole |
1–2 weeks | 6–8 months | Not recommended |
| Celery Whole |
1–2 weeks | 8–12 months | Not recommended |
Reviewed 2026-09-20. Times follow published USDA FoodKeeper / FSIS, FDA and CDC storage guidance; where sources differ we use the shorter time. How we compile this data.