Oats are the kind of food you buy knowing they last for ages. You don’t have to worry about them, and you’ll eat them eventually.
Unfortunately, for a lot of us, that means we can forget about them for months until we find the bag past the expiration day.
If this sounds like you, then you’re in the right place, as we’re running through how to store oatmeal, how to tell if oatmeal has gone bad, and how long you can expect your oatmeal to last.
Does It Go Bad? The Short Answer

Oatmeal is known as a breakfast favorite for many people. If you can get through a bag of oatmeal within weeks, you will probably never have to worry about its expiration date. However, if you don’t cook oatmeal regularly, you might be wondering when it is good until.
The truth is that both raw oatmeal (oats) and cooked oatmeal can go bad.
Oats, when stored properly, can last between one to two years, usually months past their “best by” date in good storage conditions. However, it is useful to keep in mind that even though it might be safe to eat oats past their best-by date, their quality, flavor, and nutritional values might change.
If, on the contrary, you decide to make a big batch of cooked oatmeal and you are wondering how long you can keep it in the fridge: the answer is 4-6 days.
If you left your cooked oatmeal outside of the fridge for over 2 hours (at room temperature), it’s time to throw it away.
How To Tell If Your Oatmeal Has Gone Bad

If you have gotten to the point that your raw oats are probably not edible, here are the signs to look for to confirm.
- Mold – sometimes not extremely obvious. It can be settled at the bottom or corners of the box. Make sure to stir and check the packaging.
- Change in color – fresh oats are usually cream or light brown. Anything lighter or darker could be a sign of bad oats.
- Clumps – if your oats are sticking and clumping together, they’re no good to eat!
- Smell – if the oats have turned rancid due to long storage, the chances are they will have a sour smell to them.
There is the possibility that your oats look and smell fine but tasting them will give you the last hint. They might be stale and flavorless if the quality has gone down or even sour if they are rancid.
How To Store Oatmeal

The key to improving oats’ shelf life and keeping them fresh for longer rests in the right container.
Raw oatmeal (oats) should always be stored in an airtight container to reduce the risk of exposure to air and water. Moisture can very quickly ruin your year-lasting oats, so make sure they are kept in a cool, dark, and dry cupboard. If you have a pantry, that’s ideal!
If you consume oats regularly, consider purchasing a container and keeping it just for your oatmeal, avoiding the oats to absorb other foods’ flavors.
Cooked oatmeal, on the other hand, should always be stored in the fridge. Make sure you have left it to cool down for a bit before refrigerating them, usually between 20-40 minutes.
Can Expired Oats Make You Sick?

The rancidification of oats is the result of fat oxidation. In this case, eating expired oats as a one-time thing might not necessarily make you sick or ill. However, the regular intake of rancid oats will make you ill, and it can cause some trouble to your digestive system. So stick to fresh oats!
How To Use Leftover Oats
If your oats are past their best-by date and you are not too sure if you want to eat them on their own, don’t throw them out!
If you still wanna enjoy their nutty flavor, you could definitely bake them. Anything from cookies, pancakes, muffins, and flapjacks, the list is infinite!
If baking isn’t your thing, maybe non-dairy milk works for you. Try to make your own oat milk. Just blend your oats with some water and honey, filter them, and you’ve got some easy homemade oat milk!