How to Freeze Onions

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It’s easy to freeze onions to use in your favorite recipes. Prevent waste and save money and time by freezing excess onions from your garden or the store.

I confess…the idea of freezing onions isn’t one that often crosses my mind. But when I saw a 10 pound bag of onions for $4 at Costco, it was a deal I couldn’t pass up.

Holy moly, 10 pounds of onions is a lot of onions to use up…

I made stir-fry.

I made a double batch of Crock Pot Spaghetti Sauce.

I chopped and sauteed some to add to Baked Italian Meatballs. And we still had tons of onions left!

While onions can be dehydrated or canned, it’s easiest to preserve your bounty by freezing them. Raw onions freeze well, and they can be used in any cooked recipe.

I’m using yellow onions here, since that is what was on sale. But this technique will work with white onions, yellow onions, red onions, or shallots. Freezing is also a great way to save a bit of onion that’s leftover from a recipe, so it doesn’t go to waste.

Here’s how easy it is to freeze your onions!

How to Freeze Onions

Peel the onion, trim the top and root end, and chop it to a small dice. You can do this with a knife, but I prefer to use my food processor. (This is my favorite food processor–so easy to use and clean!) A few pulses and you have chopped onions with no tears.

It’s not a good idea to freeze whole onions. Once frozen, they’ll turn into a solid block that will be nearly impossible to chop and use. Take a few minutes now to chop your onions for easier use later.

Tip: if your hands smell like onions after chopping, wash them and then rub a drop of lemon essential oil on your hands.

Put your chopped onions in a thin layer on a cookie sheet lined with a silicone baking mat. It’s OK if the onion pieces touch each other, but try to keep them in a single layer.

You might be tempted to pile all your onions pieces in a bowl and freeze them that way, but please don’t…you’ll see why in a minute.

Cover the cookie sheet tightly with aluminum foil and set it in the freezer, trying to keep it as level as possible. Make sure the aluminum foil is tightly sealed so the onion smell doesn’t leak out and stink up the freezer.

Leave the onions in the freezer until they’re completely frozen–at least 2 hours. Then take the cookie sheet out of the freezer. See how the onion bits are individually frozen? Freezing them flat on the cookie sheet makes it easy to use and store them.

Here’s why you don’t want to just pile the onions in a bowl and stick the bowl in the freezer. You’ll end up with an onion popsicle!

How to Store Frozen Onions

Since your onions are NOT an onion popsicle, you can store the entire batch in a large freezer bag. Label the bag and press out as much air as possible before putting it in the freezer.

Your onions will keep in the freezer for up to 6 months, but I bet you’ll use them up long before then.

How to Use Frozen Onions

It’s easy to use your frozen onions. You don’t even have to thaw them before cooking with them! Measure out exactly the amount you need from your freezer bag and toss it back in the freezer.

If your recipe doesn’t specify a measurement, here are good estimates:

Small onion: ½ cup chopped frozen onion

Medium onion: 1 cup chopped frozen onion

Large onion: 1½ cups chopped frozen onion

Freezing onions does not ruin them, but it does change their texture. Because of this, you’ll want to use frozen onions in cooked recipes–not fresh dishes like salsa or potato salad.