Does Soy Milk Go Bad?

Shelf-stable soy milk keeps for at least a couple of months past the date on the label. Once you open the carton, the drink stays good for about a week or so.

When it comes its counterpart that’s sold refrigerated, it comes with a relatively short shelf life and keeps for only a few days after opening.

But even if your soy milk is well within its date, or you opened yours only a few days ago, you still need to know how to tell if it’s bad. Otherwise, you’re not really sure if yours is safe to use or not.

That’s where this article comes in. In it, we talk all about storage, shelf life, and spoilage of soy milk.

Interested? Read on.

Soy milk in hand

How To Store Soy Milk

Storing soy milk is pretty similar to storing other milk alternatives, such as almond milk, coconut milk, or oat milk. While soy milk is unopened, proper storage depends on the kind of soy milk.

If it’s shelf-stable soy milk (sold unrefrigerated), then you should store it in a cool, dry place, e.g., in the pantry. Storing it in the fridge isn’t a bad idea, but it won’t help that much.

If your soy milk was sold refrigerated, that’s another story. It has to be kept in the fridge.


Only a few brands sell gluten-free soy milk, so if you have celiac disease or are sensitive to gluten, check the package before buying.

Once you open the carton, no matter if it’s the shelf-stable kind or not, you should store it in the fridge. If it’s stored in a warmer place, its shelf life will shorten noticeably.


If possible, store soy milk in the middle of the fridge, away from the door. The closer the door, the higher temperature fluctuations, which you want to avoid.

When it comes to homemade soy milk, always keep it refrigerated.

Soy milk closeup
Soy milk closeup

Can You Freeze Soy Milk?

If you need to store soy milk for an extended period, you can also freeze it.

Please note that soy milk will lose some of its taste and the texture will change after thawing. Therefore, it’s best to use thawed soy milk only in cooked dishes. This way the change of texture won’t be that noticeable.

When it comes to thawing, choose the fridge, not the countertop.

Here’s how to freeze soy milk in an ice cube tray:

  1. Pour the soy milk into an ice cube tray.
  2. Put the tray into the freezer and keep it there until the cubes freeze.
  3. Get the tray from the freezer and transfer the cubes into freezer bags or an airtight container.
  4. Chuck the bags or container back into the freezer.

When you freeze soy milk it won’t spoil, so theoretically you can store it for an indefinite period. Please note, however, that it’s recommended to freeze soy milk only for a couple of months, to preserve possibly good quality.

Want to know more about freezing soy milk? Check out our guide to freezing this lactose-free milk.

A carton of Alpro soy milk

How Long Does Soy Milk Last

While soy milk is unopened, shelf life depends on whether the milk is shelf-stable, or not.

The former should be fine for about 8 months to a year after the production date. There should be a best by date on the package, and the soy milk should be safe to use for at least a few weeks or even months.

Please remember that the best by date only informs you how long the product will remain at peak quality. It’s not an expiration date.

If your soy milk is refrigerated, it should be fine for about a week or so past the date on the package.

Once you open the soy milk carton or bottle (and store it properly), it should last for at least a week, maybe two. If you don’t store it well, it might spoil within a couple of days.

Homemade soy milk, since it doesn’t have any preservatives, will last only a few days if refrigerated.

Shelf stable (Unopened)“Best by” + 2 – 4 months 
Shelf stable (Opened) 7 – 10 days
Refrigerated (Unopened) “Best by” + 3 – 5 days
Refrigerated (Opened) 3 – 7 days
Homemade 3 – 5 days

Please note that the dates above are approximate.

Soy milk in a glass
Soy milk in a glass

How To Tell If Soy Milk Is Bad

It’s pretty easy to tell if soy milk (gluten-free or not) has gone bad.

The first thing you should do is to smell the soy product. If it has an off odor, it’s probably spoiled, and you should discard it. Fresh soy milk should have a mild smell (you probably know how fresh soy milk smells like), so if you notice a difference in smell, the milk is probably off.

You should also examine the package and the liquid itself. If the package is abnormally bloated, you can be almost sure that the milk is spoiled.

You should always pour the milk into a glass or a cup before drinking. There are at least two reasons why you should do that.

The first one is that if you drink soy milk directly from the package, some bacteria from your mouth can get into the milk and accelerate the process of spoilage. The second one is that you can quickly examine the texture of the liquid. If the milk is thick, has lumps or curds (similarly to cow’s milk) then it’s spoiled, and you should throw it away.

Soy Milk FAQ

Does soy milk go bad at room temperature/not refrigerated?

That depends on the situation. If it’s the shelf-stable kind and the carton is unopened, room temperature is just fine.

If it’s not the shelf-stable kind or the carton is opened, keeping it at room temperature will speed up the deterioration process. That doesn’t mean that it will go bad right away or within a few hours. That means that it will go bad a few days faster than it otherwise would.

If it’s already opened for a few days and you accidentally left soy milk out overnight, throw it out to be safe. If you’ve just opened it and left out overnight, it should still be fine in the morning. Just check for any signs of spoilage before drinking.

If you left out overnight an unopened carton of refrigerated soy milk, there are a few possibilities. If the best-by date is pretty far away, the non-dairy milk alternative should be safe to use. Just make sure you use it within a few days. If it’s already pushing the best-by date, you can check if it’s still usable, or toss it out to be safe. If you decide to give it a go, always check it thoroughly before using it.