How Long Onions Last in the Refrigerator and How to Store Them Properly

Onions last three to four weeks in the refrigerator when stored correctly

A whole, uncut onion will keep for three to four weeks in your refrigerator's crisper drawer or on a shelf. The cold slows the natural ripening process and prevents sprouting. Once you cut an onion, it lasts only seven to ten days, even when wrapped tightly. The exposed flesh oxidizes and dries out faster than you might expect, and the sulfur compounds that give onions their smell intensify over time.

Temperature matters more than you might think. Onions store best between 32°F and 50°F—your refrigerator's crisper drawer hits this range reliably. Leaving onions on the counter at room temperature shortens their life to two to three weeks, and they'll start to soften and sprout sooner. If your kitchen is warm or humid, the refrigerator is your better choice.

Key Takeaways

• Whole onions last three to four weeks in the refrigerator crisper, but only seven to ten days once cut.
• Store uncut onions in a breathable container or paper bag, not a sealed plastic bag, to prevent moisture buildup and mold.
• Cut onions should be wrapped tightly in plastic wrap or stored in an airtight container to slow oxidation and odor spread.
• Onions with visible soft spots, sprouting, or mold should be discarded, as decay spreads quickly in the cold.
• Frozen onions last up to three months and work well in cooked dishes, though they lose their crisp texture.

Why whole onions need air circulation, not a sealed bag

Whole onions release moisture as they age, and that moisture needs somewhere to go. A sealed plastic bag traps humidity against the onion's skin, creating the exact conditions mold and rot need to take hold. Instead, store whole onions in a paper bag, a mesh produce bag, or the crisper drawer's open compartment. These containers let air move around the onion while keeping it separate from other produce.

If your crisper drawer tends to stay very wet—you'll notice condensation on the glass—place a paper towel on the shelf before setting onions down. The towel absorbs excess moisture without blocking airflow. Check your onions once a week. A soft spot or wrinkled skin means that onion is beginning to break down; remove it before decay spreads to the others.

How to store cut onions so they don't dry out or smell up your fridge

Once you cut an onion, the exposed flesh begins to oxidize immediately. Wrap the cut side tightly in plastic wrap, pressing it directly against the cut surface to minimize air exposure. Store the wrapped onion in the coldest part of your refrigerator—usually the back of a shelf or the bottom of the fridge, not the door. The door experiences temperature swings every time you open it, which speeds decay.

Alternatively, place cut onions in an airtight container with a tight-fitting lid. Glass containers work better than plastic for this purpose because they don't absorb onion odor the way plastic does. Even in an airtight container, cut onions will smell strong after a few days—that's normal and doesn't mean they've gone bad. The smell comes from sulfur compounds being released, not from spoilage. Discard them after ten days regardless, because the flesh will begin to soften and lose flavor.

Signs an onion has gone bad and should be thrown away

A soft, mushy texture is the clearest sign an onion is no longer good. Press gently on the outside; it should feel firm. If your finger leaves an indent or the onion feels hollow inside, discard it. Mold appears as fuzzy white, green, or black patches on the skin or inside the layers. Even a small patch means the entire onion should go—mold spreads through the flesh faster than you can see.

Sprouting is not dangerous, but it means the onion is using its stored energy to grow. A sprouted onion will taste bitter and woody. If sprouting has just begun—a small green shoot at the top—you can cut that part away and use the rest. Once sprouting is advanced, the onion's flavor has already shifted; it's better to replace it. A sour or fermented smell, distinct from the normal sharp onion smell, means bacteria have begun to break down the flesh. Trust your nose—if something smells off, throw it out.

Freezing onions for longer storage

If you have more onions than you can use in four weeks, freezing extends their life to three months. Peel and chop the onions into your preferred size, spread them on a baking sheet, and freeze for two to three hours until solid. Transfer the frozen pieces to a freezer bag or airtight container, removing as much air as possible. Frozen onions work well in soups, stews, sauces, and cooked dishes where texture doesn't matter.

Frozen onions will be softer and release more liquid when thawed because ice crystals rupture the cell walls. Do not thaw them before cooking; add them directly to the pot. They'll break down faster than fresh onions, which actually speeds up cooking time. Frozen onions are not suitable for raw applications like salads or salsas, where crispness is important.

Organizing your crisper so onions stay fresh longer

Keep onions separate from ethylene-producing fruits like apples, pears, and avocados. These fruits release ethylene gas, which speeds ripening and sprouting in onions and potatoes. If your crisper has two drawers, use one for onions and potatoes and the other for fruits. If you have one drawer, place onions in a paper bag on one side and fruits on the other, with as much distance as possible between them.

Store onions away from direct contact with the crisper's back wall if it tends to get very cold or wet. Some refrigerators have a cold spot where the cooling coil is closest to the interior, and onions stored there can freeze or develop ice crystals. The middle or front of the crisper is usually the safest spot. Check the temperature of your crisper with a refrigerator thermometer if you're unsure—it should read between 32°F and 40°F.

Red, yellow, and white onions have slightly different storage times

Yellow onions are the most common storage onion and last the full three to four weeks. Red onions have thinner skin and slightly higher water content, so they last about three weeks. White onions are the most delicate and may begin to soften after two to three weeks. Sweet onions like Vidalia have even higher water content and should be used within two weeks. Store all varieties in the same way—the difference is how long they hold up, not how you care for them.

Spring onions and scallions are different from storage onions and should be treated like fresh herbs. Trim the roots, stand them upright in a jar with a little water, cover loosely with a plastic bag, and refrigerate. They'll last about a week this way. Do not store spring onions with regular onions; they need higher humidity and more frequent use.

Frequently Asked Questions

Can I store onions in the refrigerator door?

The door is the warmest part of the refrigerator and experiences temperature swings every time you open it. Onions will last longer in the crisper or on a shelf. If space is tight, the door is acceptable for a week or two, but move them to the crisper if you want them to last the full three to four weeks.

Why did my onion turn blue or green inside?

This is a natural reaction between sulfur compounds in the onion and copper or iron in your knife or cutting board. It is not mold or spoilage and is completely safe to eat. Wash your knife and cutting board with soap and water, and the discoloration won't happen next time.

Is it okay to eat an onion that has started to sprout?

Yes, as long as there is no mold or soft spots. Cut away the sprouted part and use the rest. The onion will taste slightly bitter because energy has gone into the sprout, but it is not unsafe. If sprouting is extensive, the flavor change is noticeable enough that you may prefer to discard it.

How do I stop cut onions from making my whole refrigerator smell?

Wrap the cut side tightly in plastic wrap and store in an airtight container with a tight lid. Place a small open container of baking soda on a nearby shelf to absorb odors. Replace the baking soda every few days. The smell will fade once you use or discard the onion.

Can I store raw onions and cooked onions together?

Yes, they can share the same shelf or container. Cooked onions last three to four days in the refrigerator. Store them in an airtight container separate from raw onions to prevent cross-contamination and to keep the raw onions from absorbing the cooked onion smell.