How are sunflower seeds scattered

Do sunflower seeds go bad?

Have you found an old pack of sunflower seeds and are not sure whether you can still eat them or not? Chances are you bought them to snack on while watching the game and forgot about them in all the fuss.

Now, a few months later, the package is still in the closet in the pantry where you threw it away. Do sunflower seeds go bad?

In this quick guide, we'll talk about sunflower seed storage, shelf life, and spoilage. If you are interested, read on.

Sunflower seeds in a black scoop

How to store sunflower seeds

There are a number of options when buying sunflower seeds. You can buy them in the shell or peeled (sunflower seeds), roasted, salted, and sometimes even flavored. But regardless of the variety, the same storage guidelines apply.

In supermarkets, sunflower seeds are on the shelves near trail mix and many types of nuts. And while this setting is far from ideal, it is fine for a short time (i.e. a couple of months). If you buy the pack for the snack during the game next week, it's okay if it's at room temperature. Just make sure it's in a dry place and out of sunlight and you're good to go.

But if you've bought the seeds in bulk or need to store them for more than a month or two, a cupboard in the pantry won't be enough. A much better option would be to refrigerate them in an airtight container in the fridge or freezer (HL). The cold temperature helps protect the seeds from rancidity, the most common cause of "spoilage" in sunflower seeds.


To extend the shelf life of sunflower seeds and seeds, they should be stored in low-oxygen packaging (NSA). So if you bought the kernels loose or have already opened the package, put them in a resealable freezer bag and blow the air out before sealing.

Sunflower seeds close-up

How long do the sunflower seeds last

While I could probably offer you separate storage times for unpeeled, peeled, roasted and unroasted sunflower seeds, the differences between these are quite small. So I'll keep things simple.

In the case of commercially packaged sunflower seeds, the best-before date on the label must be observed. It's by no means an expiration date, but it is an excellent place to start. If the package is left unopened at room temperature, the seeds should retain their quality for a few months after the expiration date. If you decide to refrigerate or freeze them, expect an additional shelf life of at least one year.

Sunflower seeds in a white cloth bag

With sunflower seeds bought loose or in an opened package, the time it takes to keep the quality at its best is much shorter. If you keep the seeds tightly closed in a cupboard in the pantry, they should be stable for at least 2 to 3 months. To extend the shelf life to a full year, they should be refrigerated or frozen.



Commercially packaged sunflower seeds (unopened)

Best before date + 2 months

Best time + 12 months

Sunflower seeds (open package or bought loose)

2 - 3 months

12 months

Please note that the above periods are estimates and are only intended to provide the best quality. It is not unlikely that you will find seeds that go well beyond these time periods and are still good to eat.

Heap of sunflower seeds

How do you know if sunflower seeds are bad?

The signs of spoilage in oil-containing seeds such as sesame, pumpkin or sunflower seeds are quite similar. Here are things to look out for:

  • Rancid or sour odor. The first type of spoilage for oily seeds is to go rancid. Rancidity is essentially the oxidation of oils through exposure to air, light or moisture (WIKI). You won't get sick after eating rancid sunflower seeds, but the smell (and usually the taste) is pretty bad. Throw them away when the seeds smell away.
  • Tasteless. Sometimes it is not immediately apparent that the seeds are spoiled because of their aroma. If that's the case, give one or the other a taste to make sure the quality is still okay. If the kernels taste sour, get rid of them.
  • Mould. Mold comes last because it is pretty unlikely to show up. If you follow storage guidelines and don't put water in the package, there will most likely be none.


If you're not entirely sure whether the seeds are good to eat, throw them away. Human intuition when it comes to discovering foods that are not safe to eat is quite good. If you feel like there is something wrong with the seeds, trust instinct.

Sunflower seeds


  • National NSA Sunflower Association: Shelf Stability Study
  • HL Health Line: Sunflower Seeds: Diet, Health Benefits, and How to Eat Them
  • WIKI-Wikipedia: Getting rancid