How Long Does Onion Last in the Fridge? Expert Guide

You open the fridge and see an onion you forgot about last week. You wonder, is it still good to eat? We’ve all been there. The exact answer is that a whole raw onion lasts up to 2 months in the fridge if stored the right way, while a cut onion stays fresh for about 7 to 10 days. In this article, you’ll find easy and full tips to make sure your onions stay fresh longer and avoid wasting food.

Understanding How Long Onions Can Stay Fresh in the Fridge

When you put onions in the fridge, how long they last depends on how they are stored. A whole onion, if it’s unpeeled and kept dry, can last up to 2 months in the fridge. But once you cut it, that changes. Cut onions can go bad quickly if not stored in an airtight container. Usually, cut onions last 7 to 10 days. Cooked onions have an even shorter life. They stay good for about 3 to 5 days.

Onions are like any other vegetable. They have moisture inside. If they are exposed to air, that moisture can help bacteria grow. That’s why it’s important to store onions the right way. If they start to feel soft, smell weird, or grow mold, it’s time to throw them out.

Fridges are great for keeping onions cool and slowing down the rotting process. But they also bring moisture. That’s not good for onions unless they are stored right. If you keep a whole onion in the fridge, don’t put it in a plastic bag. That can trap moisture. Instead, use a paper bag or a mesh bag. It allows the onion to breathe.

Cut onions should always go in a sealed container. If you leave them uncovered, your whole fridge will smell like onions. Also, they will dry out fast and turn bad. A clear plastic or glass container works best. You can see inside and check the onion without opening it.

Cooked onions are different. Once onions are cooked, they should be placed in a container with a lid. That keeps out air and stops the growth of bacteria. Cooked onions don’t last long, even in the fridge. After about 3 to 5 days, they may taste sour or feel slimy. That means they’re not safe to eat anymore.

Sometimes people freeze onions to make them last even longer. You can freeze cut onions and cooked onions. But freezing changes the texture. They won’t be as crisp when thawed. Still, it’s a good way to stop waste and save onions for cooking later.

Freshness also depends on the type of onion. Red, white, yellow, or sweet onions have slightly different shelf lives. Sweet onions have more water, so they don’t last as long as yellow ones. Always check the onion by looking and smelling. A fresh onion feels firm and has a clean smell.

How long your onion lasts in the fridge really comes down to these things: the type of onion, whether it’s cut or whole, how it’s stored, and the fridge temperature. A fridge set to about 40°F (4°C) works best.

• Whole unpeeled onion: up to 2 months in fridge
• Cut raw onion: 7 to 10 days in airtight container
• Cooked onion: 3 to 5 days sealed in container
• Sweet onions: shorter shelf life than yellow ones
• Use glass or plastic containers to store cut onions
• Check for signs of rot like mold, slimy feel, or bad smell

Knowing the Signs When an Onion Goes Bad

It’s not always easy to tell when an onion has gone bad, but there are clear signs you can look for. If your onion has dark spots, mold, or smells sour, it’s no longer good. A fresh onion smells like an onion—strong but not rotten. Once it smells bad, it’s time to throw it out.

Another sign is the texture. If an onion feels too soft or mushy when you squeeze it, it has started to go bad. A healthy onion should feel hard and firm. Even a little softness can mean it’s on the way to spoiling.

Color is also important. A fresh onion has a bright skin. It may be brown, red, or white depending on the type. But if the color changes to something dull or there are black or green spots, it’s a sign of rot or mold. Mold can grow inside the onion layers too, not just on the outside.

Sometimes the onion may sprout green shoots from the top. This doesn’t always mean it’s bad, but it does mean it’s getting old. You can still use the parts that look and smell fine. Just cut off the green sprout and check the rest.

Smell is often the first thing you’ll notice. A spoiled onion has a very strong, sour smell. You may even smell it before opening the container. That’s your biggest warning. Don’t risk eating it.

Onions that are slimy should never be used. That slime is bacteria. Even if just part of the onion looks bad, the whole onion might be unsafe. It’s better to be safe and throw it away.

Another thing to check is the storage area. If your onion has been sitting near water or in a damp place in the fridge, it’s more likely to go bad. Moisture is one of the main reasons onions rot faster.

Some people try to save onions by cutting off the bad parts and using the rest. But this is risky. Bacteria can spread inside the onion. Even if it looks okay, it might not be safe. If in doubt, throw it out.

• Smells sour or rotten
• Feels soft, mushy, or slimy
• Has mold or dark spots
• Color turns dull or changes
• Grows green shoots (means it’s old)
• Was stored in a damp fridge area
• Cut parts may spread spoilage inside

Best Ways to Store Onions in the Fridge

Storing onions the right way can make a big difference. If you just toss them in the fridge, they might not last long. But with the right tips, you can keep them fresh for weeks.

First, think about whole onions. If the onion is unpeeled, it should be stored in a cool, dry part of the fridge. Do not place it in a plastic bag. Plastic holds moisture, and moisture is not good for onions. Instead, use a paper bag or mesh bag. These let air move around and help stop mold.

If your fridge has a crisper drawer, use that. It’s designed to keep vegetables fresh and has lower humidity. But still, check that it stays dry. A small towel in the drawer can help take in extra moisture.

Now for cut onions. Once you cut an onion, always put it in an airtight container. A glass container with a lid is best, but plastic works too. Avoid foil or plastic wrap alone—they don’t seal the onion properly. Air and moisture can still get in, and your fridge may start to smell.

Some people like to use onions fast after cutting. That’s okay too. But if you’re saving it, try to use it within 7 to 10 days. Write the date on the container so you remember.

Cooked onions also need care. They go in a sealed container and should be eaten within 3 to 5 days. You can freeze them if you need to save them longer. Just cool them fully first before putting them in the freezer.

Avoid putting onions near foods that take on smells, like milk or butter. Onions have a strong odor that can spread in the fridge. Keeping them sealed stops that.

If you buy peeled onions from the store, make sure to use them quickly. They don’t last as long. They should always be kept in a sealed package and used within a few days.

Don’t wash onions before storing them. Wet onions go bad faster. Only wash them when you’re ready to use them.

• Whole onions: cool, dry place in fridge in paper or mesh bag
• Cut onions: airtight container, 7 to 10 days max
• Cooked onions: sealed container, eat within 3 to 5 days
• Avoid plastic bags and open air
• Don’t store near smell-sensitive foods
• Write the date on containers
• Never wash before storing

Why the Type of Onion Affects How Long It Lasts

Not all onions are the same. Some last longer than others. The type of onion you use makes a big difference in how long it stays fresh in the fridge.

Yellow onions are the most common and last the longest. They have a dry outer skin and less moisture inside. That means they don’t spoil as fast. If stored right, a whole yellow onion can last up to 2 months.

White onions have a sharp taste and also last long, but not quite as long as yellow onions. They have a little more water inside, so they may go bad faster if not stored well.

Red onions are popular for salads and burgers. They have more sugar and moisture, which means they spoil quicker. Keep them in a sealed container and eat them within 7 to 10 days if cut.

Sweet onions, like Vidalia onions, are tasty but go bad fast. They hold a lot of water. That makes them more likely to grow mold or turn soft in just a week or two. If you buy sweet onions, plan to use them quickly.

Shallots are in the onion family too. They’re smaller and milder, but they last a long time. If stored whole, they can stay fresh for a month or more in the fridge.

Spring onions or green onions have a short life. Once you buy them, they should be used within 5 to 7 days. They wilt fast, even in the fridge. Wrap them in a damp paper towel and put them in a plastic bag.

Each type has a different shelf life. Knowing what type you have helps you decide how to store it and when to eat it.

• Yellow onions: 1 to 2 months
• White onions: up to 1 month
• Red onions: 2 to 3 weeks
• Sweet onions: 1 to 2 weeks
• Shallots: up to 1 month
• Green onions: 5 to 7 days

How Temperature and Humidity Change Onion Shelf Life

Fridge temperature plays a big role in how long onions last. The best temperature for storing onions is around 40°F (4°C). If it gets too cold, onions may freeze. If it’s too warm, they rot quicker.

Humidity also matters. Onions like dry air. Moist air speeds up rot. That’s why storing onions in the crisper drawer with a paper towel works well. It keeps the moisture level down.

If your fridge has too much moisture, onions may start to sweat. This makes them soft and mushy. They won’t last long. Use a paper towel or open container to help soak up extra moisture.

Some people use containers with air holes to store onions. This lets air flow and keeps the onions dry. Others use mesh bags, which are great for airflow.

You should also avoid putting onions near the fridge door. That area changes temperature often. Inside the fridge, away from the door, is better.

If your kitchen is too warm, it’s better to keep onions in the fridge. But if it’s cool and dry, a pantry might work too for whole onions.

• Best temperature: 40°F (4°C)
• Avoid warm or freezing temps
• Use crisper drawer if dry
• Use paper towel to control moisture
• Don’t store near fridge door
• Use containers with airflow or mesh bags
• Kitchen must be cool and dry for pantry storage

Tips to Make Your Onions Last Longer in the Fridge

To make onions last as long as possible, small habits help a lot. First, always check onions before you buy them. Pick ones that are firm, dry, and have no spots. If you start with good onions, they will last longer.

Once you get home, store them right away. Whole onions don’t need a container but should stay dry. Cut onions should go straight into a sealed container. Label it with the date.

Use older onions first. Follow the ‘first in, first out’ rule. This helps you use onions before they go bad.

If you see part of an onion starting to rot, use it quickly or toss it. One bad onion can spoil others around it.

Try not to touch cut onions with wet hands. Water helps bacteria grow. Always use a clean, dry spoon or fork if you’re taking out part of a stored onion.

Store different types separately. Don’t mix sweet onions with red or yellow ones. Their moisture levels are different.

If you want onions to last even longer, chop them and freeze them. They won’t stay crisp, but they’re great for cooking.

• Buy fresh, firm onions
• Store right after bringing home
• Use sealed containers for cut onions
• Label containers with dates
• Use older onions first
• Avoid touching onions with wet hands
• Keep types separate
• Freeze for longer storage

Onion Fridge Storage Time Table

Final Thoughts

Onions are a big part of many meals. Knowing how to store them the right way saves you time and money. The fridge helps onions stay fresh, but only if you store them correctly. Whole onions can last up to 2 months, while cut ones need to be eaten in about a week. Always check for signs of spoilage like smell, texture, and mold. With these easy tips, you can enjoy fresh onions and waste less food.

Frequently Asked Questions (FAQs)

Is it safe to eat an onion that smells strong in the fridge?

If the smell is stronger than normal and seems sour or rotten, it is not safe to eat. Onions do have a natural strong smell, but it should be sharp and fresh. A bad smell means bacteria might be growing. If your onion also feels soft or looks odd, it’s best to throw it away. Always trust your nose when checking if food is still okay. A strong bad smell is a clear warning sign. Keep onions in sealed containers to avoid this problem.

Can cut onions be stored without a container?

No, cut onions should never be stored without a container. Leaving them open in the fridge lets them dry out and also makes your fridge smell bad. More importantly, they can catch bacteria from other foods. Always use a container with a tight lid. This keeps the onion fresh and safe to eat. Glass or plastic containers work best. Do not use foil or wrap alone because it doesn’t fully block air. A container is the best way to keep onions fresh longer.

Do I need to wash onions before putting them in the fridge?

You should not wash onions before storing them in the fridge. Water adds moisture, and moisture can make onions go bad faster. Only wash onions right before you plan to use them. If you wash them before storage, they can grow mold or turn soft. Keep them dry and in the right kind of bag or container. Dry storage helps stop bacteria and keeps them fresh longer. Remember, dry onions are happy onions in the fridge.

Is it okay to freeze onions?

Yes, you can freeze onions. Cut or cooked onions freeze well. They won’t be as crisp after freezing, but they’re still great for cooking. Just chop the onion, put it in a freezer-safe bag or container, and freeze. You can even freeze them in small portions. Label the bag with the date so you know how long it’s been. Frozen onions can last 3 to 6 months. Don’t freeze whole raw onions, as they don’t thaw well.

Can I store onions in a plastic bag?

It’s better not to store whole onions in a plastic bag. Plastic bags trap moisture, and that makes onions go bad faster. Onions need air to stay dry and fresh. Use mesh bags, paper bags, or containers that allow air to move. If you already cut the onion, then a plastic container is fine because it’s sealed and keeps the smell inside. But for whole onions, always go for bags or containers that let onions breathe.

Do I need to keep cooked onions in the fridge?

Yes, cooked onions should always go in the fridge. Leaving them out for too long can cause bacteria to grow. Once they cool down after cooking, put them in a sealed container and place them in the fridge. They will stay fresh for about 3 to 5 days. If you wait too long, they might get a sour smell or turn slimy. Never leave cooked onions out overnight. Always store them safely to avoid food poisoning.

Is it okay to eat onions with green sprouts?

Onions with green sprouts are not dangerous, but they are old. The sprout grows when the onion starts to age. You can still eat the onion if it looks and smells okay. Just cut off the green part and check the rest. If the onion is soft or smells bad, then don’t use it. Sprouting onions may not taste as good, but they are safe if stored properly. It’s best to use them soon after sprouting.

Can onions make other food in the fridge go bad?

Yes, onions can affect other foods in the fridge. They have a strong smell that can spread if not sealed properly. Some foods like milk, butter, and fruits can take on the onion smell or taste. This is why it’s important to store cut onions in airtight containers. Whole onions don’t usually cause this problem if stored dry. Keep onions away from delicate foods and always use a sealed container after cutting to protect the rest of your food.