Quick Pickled White Onions, an easy refrigerator pickled white onions recipe in a light vinegar brine. A tasty and easy way to preserve your onions without canning!

pickled white onions in a glass jar with herbs

Love pickled white onions? So do we! This simple and quick refrigerator pickled white onion recipe takes only 2 hours for the perfect pickled onions to use as toppings for burgers, salads, and tacos.

👉 Ready to learn how to quick pickle white onions? Let’s do it!


🧅 Ingredients

  • Onions: white onions are the foundation of this recipe, but this process can work with any type of onion
  • Vinegar: adds tang to the brine and also preserve the onions
  • Water: the base of the brine and dilutes the vinegard
  • Mustard: adds flavor to the brine, we're using mustard seeds but you can also use stone ground
  • Herbs: any herbs you have on hand will work to add flavor, we like dill and sage (pictured here)
  • Salt and sugar: adds flavor to the brine and helps to preserve the onions
  • Recommended tools: small sauce pan, glass jar, knife, cutting board
an onion and bowls of water, vinegar, salt, and sugar on a table for pickling
Ingredients: white onion, water, vinegar, salt, sugar, herbs

🥣 How to make (step-by-step photos)

1️⃣ Step One: Prep white onions

The first step is to wash and prep the white onions for pickling. To do this, simply cut the stems from the onion, slice it in half, and then remove the onion's outer layer.

Then cut each onion half into thin slices so you have very thin white onion strips that will easily soak up the pickling brine.

sliced onions on a cutting board with bowls of sugar, salt, and vinegar
Slice onions

2️⃣ Step Two: Prepare the pickling jar

Next it’s time to prepare the jar that you will pickle the onion in. Choose a large, wide jar so that you can leave 1/2 inch of space after you fill the jar with the brine.

Add the white onion slices, dill (and other fresh herbs, if using), mustard seeds, garlic cloves, and red pepper flakes (optional, but we highly recommend).

cut onions in a jar with herbs before pickling
Add ingredients to jar

3️⃣ Step Three: Prepare and add the pickling brine

You can't make pickled vegetables without brine! This is what adds the “pickled” flavor to vegetables and fruit.

Our go-to refrigerator pickling brine formula is usually:

  • 2 cups water
  • 1 cup vinegar (distilled vinegar, white wine vinegar, and apple cider vinegar are our favorites)
  • 1 tablespoon salt
  • 1 tablespoon sugar (granulated white or brown)

We increase or decrease the amount of brine depending on the amount of vegetables we’re pickling, but this is the foundational recipe we use that always produces great tasting pickled vegetables.

a small sauce pan with salt and sugar inside on a white table with a measuring glass of water and a bottle of apple cider vinegar
Add salt, sugar, vinegar, and water to pan

To make the brine:

  1. Add water, a vinegar of your choice (see our tips for vinegar below), salt, and sugar to a medium saucepan and bring to a boil.
  2. Pour the hot brine into the pickling jar and completely cover the onion slices, then close the lid tightly and allow it to cool down on the counter until it reaches room temperature.

💡 Want more tips for making pickling brine? Check out my full recipe, tips, and advice for making a refrigerator pickling brine here.

a small sauce pan filled with water and apple cider vinegar brine on a stovetop with a wooden spoon
Boil the brine, the pour over vegetables

👉 Which vinegar should you use for pickling white onions? We like a sweeter vinegar for pickling onions to bring out their natural sweetness, so we opt for apple cider vinegar or white wine vinegar. You can also choose a simple white vinegar as well.

bottles of red wine, white wine, distilled, rice, apple cider, and balsamic vinegars on a wooden table
Test out different vinegars to find your favorite brine recipe

4️⃣ Step Four: Refrigerate onion pickling jar

Once the jar is cool, put the jar into the refrigerator and allow the onions to pickle in the vinegar brine.

a jar of pickled onions with herbs on a wood table

👉 How long to quickly pickle white onions

If you want to serve quickly, let the white onions pickle for at least 2 hours. For best results, we recommend letting them soak up the brine for at least 24-48 hours.

The refrigerator pickled red onions are good up to two weeks in the refrigerator as long as they are submerged in the vinegar water.


❓ Questions and quick tips

What jar should I use for pickling white onions?

Choose a jar that's wide and tall enough to store the red onion slices. There should be about 1/2 – 1 inch (1-2 cm) of space between the slices and the lid so that they can completely submerge in the brine liquid.

How long before you can eat pickled white onions?

You can eat pickled onions after they have been in the refrigerator for at least 2 hours. However, we suggest waiting for 24-48 hours for the best results. If your onions were sliced very thin, then less time will be needed for the best flavor.

How long do pickled onions last?

As long as onions are completely covered with brine, they will last for up to two weeks in the refrigerator. If any piece of the onions are sticking out of the water, there is potential for bacterial growth, so make sure to use a tall jar and to completely submerge them in the brine.

How do I know if my pickled onions have gone bad?

Quick pickling vegetables and fruit in the refrigerator does not come with the same food safety hazards as traditional pickling and canning. However, to make sure your onions stay safe while stored in the refrigerator, make sure to completely cover them in the liquid brine and to feel them before eating. If they're slimy, throw them out.


💡 Ideas for serving

Here are a few recipes and ideas to get you started:

  • Add on top of burgers. Add pickled onions on top of veggie burgers for an acidic flavor kick.
  • Top tacos. Sprinkle a few pickled white onions on top of tacos for a flavor contrast.
refrigerator pickled onions in a glass jar on a white table

🧅 More quick pickling recipes

Check out our other easy simple vegetable recipes:

Quick Pickled White Onions

Quick Pickled White Onions, an easy refrigerator pickled white onions recipe in a light vinegar brine. A tasty and easy way to preserve your onions without canning!
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Ingredients

  • 1 large white onion
  • 1 tablespoon mustard, seeds or stone ground
  • 2 cups water
  • 1 cup vinegar, white, white wine, apple cider
  • 1 tablespoon salt
  • 1 tablespoon sugar
  • Optional: fresh herbs (dill, etc.), red pepper flakes

Instructions 

  • Prep the white onion: Cut the stems off the onion, then slice in half and remove the outer layer. Then slice each half into thin slices and set aside.
  • Prepare the pickling jar: Add sliced onions to a large jar and add mustard seeds, garlic, and optional add-ins like herbs and red pepper flakes.
  • Prepare and add the brine: In a medium saucepan bring the water, vinegar, salt, and sugar to a boil. Once boiling, pour into the jar until the liquid completely submerges the onions. Let the jar cool on the counter until it reaches room temperature.
  • Pickling instructions: Once cooled, close the lid on the jar securely and put the jar into the refrigerator and let the onions pickle for at least 2 hours before serving, but for best results serve after at least 24 hours. Quick pickled onions are good up to two weeks in the refrigerator.

Notes

  • Vinegar: White vinegar, white wine vinegar, and apple cider vinegar are the best vinegar choices for this recipe.
  • Recommended jar: Choose a large and wide jar with about 1/2 – 1 inch space (2-3 cm) below the lid.
  • Other recommended tools: small saucepan, cutting board, knife set
  • Prep ahead and storage: Refrigerator pickled onions should be made at least 2 hours before serving, but for best results make at least 24-48 hours ahead. Keep the jar refrigerated and it can be enjoyed for up to two weeks. Do not freeze.
  • Nutrition notes: Nutrition information is calculated with all brine ingredients (including full amount of sugar, salt, etc.), however the onions don’t absorb all of the liquid so the actual nutrition information is less than listed here.

Nutrition Information

Serving: 1serving, Calories: 40kcal, Carbohydrates: 7g, Protein: 1g, Fat: 0.2g, Saturated Fat: 0.03g, Polyunsaturated Fat: 0.04g, Monounsaturated Fat: 0.1g, Sodium: 1794mg, Potassium: 62mg, Fiber: 1g, Sugar: 5g, Vitamin A: 3IU, Vitamin C: 3mg, Calcium: 19mg, Iron: 0.2mg