Does Sugar Go Bad? How Long Does Sugar Really Last?

Here’s all about the shelf life, storage, and expiration of sugar. Learn whether it expires or not, what’s the best way to store it, and when to toss it.

Found a bag of sugar sitting in the cupboard for who knows how long and aren’t sure if it’s still usable? Does sugar go bad?

Or maybe you just want to know how to store sugar after opening the bag, or when you should discard an old bag.

If either sounds like you, you’re in the right place. Read on.


This article is about granulated white sugar and a couple of sugar alternatives. If you’re interested, we have separate articles on brown sugar (Does Brown Sugar Go Bad?) and powdered sugar (Does Powdered Sugar Go Bad?).

Sugar cubes
(credit: uwehermann)

Does Sugar Go Bad Or Expire?

Sugar doesn’t go bad unless it’s infested with pantry bugs or water gets to it and forms mold. If you store white sugar properly, it stays safe to use for years after the date on the label without much change in quality.

Here’s a short and a bit simplified explanation why.

Sugar is a hygroscopic substance, which means it attracts water molecules. When any bacteria lands on top of sugar, the water from the bacteria is transferred to sugar via the process called osmosis.

Osmosis moves the water from a region of higher concentration to a region of lower concentration. And since there’s pretty much no water in sugar, almost all of the water in the bacteria gets transferred to sugar. At that point, bacteria dies of dehydration.

In other words, sugar is a difficult environment for bacteria to multiply, or even live in.


Yeah, there might be some dead bacteria in your sweet tea, and that’s perfectly normal.

Sugar cubes on red background
(credit: Mae Mu)

How To Store Sugar

Main article: How to store sugar?

Store sugar in a cool and dry place, away from any sources of heat. Once you open the package, the safest way is to transfer the sugar into an airtight container.

As you can tell, you store sugar the same way you store other dry goods such as rice or a popular sugar alternative – xylitol.

The most important thing is to keep sugar away from any moisture. It usually comes in paper bags that don’t provide any protection from water, so you must take care of that yourself.


A container has the benefit of protecting the sugar from any odors and pantry bugs.

Of course, leaving white sugar in its original packaging is okay too. Just make sure water or steam can’t reach it and there aren’t any strong smells nearby.

How to store white sugar - bag sealed with a clip
How to store white sugar – bag sealed with a clip

How Long Does Sugar Last

Sugar lasts pretty much indefinitely. While the label often includes a best-by date, sugar doesn’t really go bad unless water or pantry pests get to it.

That means that your package of granulated sugar sitting in the cabinet for how knows how long is most likely perfectly fine. Just as your old table salt is okay to use.

The date on the label, often called the expiration date, is there most likely because of legal reasons and because people tend to trust food products that come with a date more. It’s not that important if your label says the shelf life of your sugar is two years or five years.


If there are some small clumps in the sugar, you can break them apart with a fork. For larger ones or lots of small ones, bring out the big guns such as an electric mixer, or a food processor.

Sugar (unopened or opened)Stays fine indefinitely
XylitolBest-by + 2+ years
ErythritolBest-by + 2+ years
Eggs and sugar
Eggs and sugar

How To Tell If Sugar Is Bad?

Sugar basically lasts forever if you store it properly, but in certain cases, you might need to discard it.

Those are:

  • There are insects or bugs in the bag, either dead or alive. In most cases, they find their way into the package and die there. If you find any, get rid of that sugar.
  • You can see mold or any other organic growth. The presence of any type of fuzz or other microbial growth (anything that looks alive, basically) indicates that water and microbes got into the package. And by water, I mean more than a few droplets. If that’s the case, grab a new bag.
  • The sugar smells off. In most cases, it’s because it caught the odor from another food. If that’s the case, feel free to throw it out for quality purposes.

Chances are that smelly sugar is perfectly fine, but if it smells off, some of that odor might transfer to whatever dish you’re using the sugar for. And, in most cases, that renders the sugar useless.

Sugar tends to form small clumps over time, and as I already mentioned in the previous section, those are perfectly fine. If need be, you can easily break them up.

FAQs about Sugar

Does Caster Sugar Go Off? How Long Does It Last?

Caster sugar, like regular sugar, lasts pretty much forever. It’s a refined white sugar that’s quite popular in Australia. It doesn’t go bad because it’s basically granulated sugar, just slightly finer than the regular one.

Sugar Alternatives

Besides sugar, there are a couple of sugar alternatives out there worth talking about. Let’s go through those one by one.


Xylitol comes with a shelf life of about two years after the production date. But as long as you store it properly, it should retain quality for months or even years longer, the same way sugar does.

This sweetener has only become popular in the last couple of years, so it’s virtually impossible to find people who stored xylitol for 5+ years to ask them if it retains quality for that long. But I’m fairly sure it does – there’s no reason it shouldn’t.

When it comes to storage rules for xylitol, they are the same as for sugar. You should store it in a cool and dry place, away from sources of heat.

Next, remember that xylitol, like sugar, is hygroscopic. That means it attracts moisture.

Because of that, try always to keep your package sealed tightly. If it’s not resealable, use a zip-lock bag or an airtight container.


Xylitol is toxic to dogs.


Erythritol, the main ingredient in Swerve, comes with a shelf life of one to two years but lasts years longer. I recently finished a bag of erythritol that was almost two years past the best-by date on the label, and the sweetener was perfectly fine.

Storage-wise, not much new here: you should keep it sealed tightly and in a cool and dry place. Besides a cupboard in the kitchen or pantry, the fridge or freezer are also good options.

While the latter two are what Swerve suggests as optimal choices, you can stick with your favorite cupboard in the kitchen and call it a day. If you’re like me, you don’t have space to store shelf-stable products in the fridge or freezer anyway.

If it gets too hot where you store your erythritol, it might start to clump. That’s not a big deal – use a food processor or a blender to remove clumpiness.


Erythritol (and Swerve) got popular because it’s a sugar alternative that tastes very similar to the real thing but comes with much fewer calories. For example, there are 88 calories in a pound of Granular Swerve, compared to 1546 in a pound of sugar.