How to Freeze Onions in a Few Easy Steps

Save time and money by freezing onions for later.

sliced red onions on cutting board

The Spruce / Ahlam Raffii

Frozen chopped onions are great to have on hand when you need to whip up dinner in a hurry. That's why grocery stores sell them and charge you for the convenience. Save money and make your own, so you have less prep work when you are putting together a dish.

You might also want to freeze leftover onion when you chop more than you need or only use half of an onion in a recipe. Learn how to prepare your own frozen onions, and avoid having to throw them away.

Frozen Onion Basics

Frozen onions work best in cooked dishes as they won't have the spring of fresh onions. You can use them in soup, stew, casseroles, and chili, or saute them with ground beef. They retain most of their flavor for three to six months when frozen.

The process is easy and takes only a few minutes. You just need:

  • Onions
  • A knife
  • Freezer bags
  • A freezer

Don't use zip-lock sandwich bags. You need thicker freezer bags to keep the frozen onions in good shape and to minimize the leakage of odor into your freezer. Because onion odor can still manage to escape and permeate your freezer, you may want to use ​an accessory freezer in your garage or basement.

Steps for Freezing Chopped Onions

Follow these simple steps to freeze your chopped onions:

  1. Peel the onions.
  2. Chop or slice the onions to the size pieces you need for upcoming recipes. Place the chopped onions in a freezer bag, squeeze out as much air as possible, and seal it.
  3. Freeze the chopped onions in bags with just the portion you would typically use in a recipe. It's better to use several smaller bags than one large bag so that you can open each bag and use up all of the frozen onion pieces contained in it. Onions don't refreeze well.
  4. Label the bag with the contents and the date that you froze them so that you'll be able to use up the oldest ones first.
  5. For the easiest storage, first, freeze the bag flat on a cookie sheet in your freezer, pressing to make it flat as possible. Bags stack better in the freezer if they are flat.
  6. When the bags have frozen solidly after a couple of hours, remove the cookie sheet and stack the bags in the freezer.

Tips

  • Chopped onions tend to freeze in clumps. To remedy the problem, just bang the bag against the counter a few times before each use. (This is another reason for using freezer bags, which are stronger than most zip-lock sandwich bags.)
  • Use your frozen chopped onions within three to six months for the best retention of flavor. In addition to freezing, there are other ways to store and cure onions so they'll be available for future use. You can also make onion powder and onion salt, saving you from having to buy expensive store-bought products.