Skip to Content

How Long Does Cake Mix Last? Best Storage Tips (2023)

If you have an expired cake mix, you may wonder how long cake mix lasts. Learn all about shelf life and how to keep cake mix fresh longer.

How long does cake mix last title

Do you love a home-baked cake? The heavenly aroma fills the air as the cake rises slowly to perfection.

Cake mixes give you the power to make a perfect cake. They are convenient, take the hassle out of baking, and make you feel like an expert baker.

If you got carried away buying cake mixes during the last cake mix sale, you might be wondering about expiration dates.

How long does a cake mix last? A cake mix does not expire. The use-by date is the recommended time frame for the cake mix’s best taste, texture, and freshness. After that date, the mix is still safe to use. However, it can taste rancid and may not rise properly when baked.

Does Your Favorite Cake Mix Expire?

You may be surprised to learn that cake mixes don’t have an expiration date. They have ”best if used by” and “best by” dates.

best if used by dates on 3 cake mix boxes

Duncan Hines cake mixes have a “best by” date. Pillsbury and Betty Crocker cake mixes have a “best if used by” date. Same thing.

According to the USDA, the “best by” dates have nothing to do with purchase or safety dates. It is simply an indicator letting you know that up until that recommended date, the best quality of the product is assured.

The USDA advises that most shelf-stable foods and packaged products (like dry mixes, cereal, etc.) are safe indefinitely. Shelf-stable or on-the-shelf foods are products that can be stored at room temperature and are non-perishable.

So, you can breathe a sigh of relief. Safety won’t be an issue.

These expiration/best by/use-by dates were only introduced in the early 1970s. I couldn’t resist asking my mom what they did before the expiry date appeared.

She laughingly recalls her mother bringing baking ingredients home in brown paper packets. No expiration dates, “best by” dates, or warnings. She says they just used common sense.

They had to because cake mixes first appeared on grocery store shelves in the late 1940s. That is over 20 years before those “best before” dates came into effect.

So let’s be honest. Lots of baking was done with old box cake mix we would now be dumping in the trash.

You may also be interested in my post about how long cake batter lasts. You may be surprised by the difference in cake mix batter vs. homemade batter.

And when you are finished baking your cake, read my article about how long cake lasts. Get tips on how to keep your cake fresh for a long time.

What Do Cake Mix Manufacturers Say About Expiration Dates?

3 cake mix boxes

Betty Crocker, Duncan Hines, and Pillsbury are the most well-known cake mix brands. These brands have been around for a long time. So, what do they have to say about expiration dates?

These cake mix manufacturers are unlikely to give us the thumbs up about using their cake mix past the recommended date.

Betty Crocker advises, “All Betty Crocker baking products have an established length of time they may be stored. After the Better if Used By date has passed, product flavor, texture, and performance may be affected. To make sure you have the best possible baking experience, we recommend using our products by the printed Better if Used By date.”

And according to Duncan Hines, there are no safety concerns when using their mixes beyond the recommended use-by date.

They say, “The reason we do not recommend using a product beyond the “Best if Used by” date is so that we can ensure quality, such as taste and texture.”

So, good news if you have an old Duncan Hines or Betty Crocker cake mix. You are safe to eat it after the expiration date.

Need the scoop on cooling a cake? Then read all my tips on how long it takes to cool cakes. You will love the hacks to speed up the process if you are in a hurry.

What is a Cake Mix Shelf Life?

open package of cake mix

The shelf life of cake mix is the time after production during which the product is still considered acceptable for consumption.

The general consensus is that the average cake mix has a shelf life of between 6 months to a year. Once the “best before date” has been reached, the peak quality of your cake mix may start to deteriorate.

But don’t worry. There is plenty you can do with an expired cake mix. See the recipes at the end for some great ideas.

What Impacts a Cake Mix’s Shelf Life?

You need to be aware of two important things that impact your cake’s shelf life:

  • The leavening or raising agents
  • How your cake mix is stored
bowl of vanilla cake mix

Leavening/Raising Agents

leavening agents - baking powder, cream of tartar, and baking soda

Cake mixes contain leavening agents like baking powder and baking soda. During the baking process, these ingredients release gasses which cause the batter to expand and, ultimately, your cake to rise. They also affect the texture of the cake.

Unfortunately, a leavening agent can lose its strength over time. This results in a less than perfectly risen cake. Or, worst-case scenario, a less durable, completely flat one.


How you store your cake mix has a significant impact on the shelf life. Especially when it comes to opened boxes with half a packet of cake mix left.

  • Store cake mixes in the unopened box they came in. Keep them in a cool dark place for best results. Before using the mix, check the outside of the box for signs of moisture, mold, or infestation.
  • The best practice for opened cake mix is to store the dry mix in an airtight container. I often store dry mixes in a zip-top bag (like a freezer Ziplock bag). Then I keep that bag in a lidded container.

Here are some things to watch out for, especially when you have an outdated cake mix.

Oxygen Exposure

open package of chocolate cake mix

An unopened package of cake mix has a long shelf life when compared to an opened mix. Oxygen exposure is limited when the ingredients are packaged in a sealed, airtight container. This prevents oxidation and rancidity from occurring.

An opened package means a shorter shelf life. The minute you open the plastic lining, the raw cake mix is exposed to oxygen. Over time, old flour takes on a rancid taste.


When your cake mix is exposed to direct sunlight or high temperatures over a prolonged period, the heat, humidity, or light may create an environment where bacteria can thrive. Proper storage is in a cool place.


As for moisture, no one wants mold growing in their favorite cake mix box! If you live in a humid environment, beware of the food safety risks.

A moist cake mix is a food safety concern because it can develop different molds, which can be toxic if consumed.

Many molds produce mycotoxins. If eaten, they can cause stomach cramps and other symptoms of foodborne illness. If you ever see any mold in the raw cake mix, throw it out.

Moisture can also interact with the dry ingredients reducing their efficacy. So, keep your dry cake mixes in a dry area.

Which Cake Mix Flavors Last the Longest?

several flavors and brands of cake mix

If you find a good sale on cake mixes, you want to stock up. You snatch your favorite flavor for sure. But if you plan to store the mixes for over a year, which type of cake mix flavors last a longer time?

I compared the ingredients of chocolate, strawberry, and vanilla cake mix to see if the different ingredients would impact the shelf life. Any product’s shelf life is determined by the ingredient which degrades the fastest.

All cake mixes have the same basic ingredients. The additional elements in a standard vanilla cake mix are natural and artificial flavors.

A strawberry cake mix also contains natural and artificial flavors and artificial coloring. Chocolate cake mixes have added cocoa and carob powder.

None of these ingredients will detract from the shelf life of your cake mix. So, you can breathe a sigh of relief if you were worried you would only be able to stock up on plain old vanilla.

Cake mix with add ins has shorter shelf life.

However, take note if your cake mix box has separate pouches to mix into the cake mix batter. These mix-ins packets can include frosting, candy, marshmallows, and dry cereal. They are often found in baking mix kits.

Sometimes these ingredients may need to be replaced if they are rancid.

What is the Best Way to Store Your Cake Mix?

Storage is the one key variable you can control. Your main objective is to limit the ingredient’s exposure to air, heat, light, and moisture.

package of Duncan Hines yellow cake mix

The best way to store your cake mix is in its original sealed packaging in a cool, dry place. And preferably a dark place like your pantry cupboard.

And what about those opened boxes with half a packet of leftover cake mix? Make sure you store them in an airtight container in a dry environment like the pantry.

Best way to store opened caked mix package

Some bakers recommend storing your cake mix in the fridge or freezer to extend the shelf life further. I haven’t found any conclusive proof either way.

But honestly, my fridge and freezer are far too full for the extra odd box of cake mix. Especially if it hides in there for a year or more.

Signs of Spoilage

Before you rush to turn on the oven, check your cake mix for any signs of spoilage. Even though the USDA says there are no safety issues for expired cake mix, other things may influence the safety of your product.

When checking your cake mix for signs of spoiling, use some good old-fashioned common sense. Just like Mom taught you.

Damaged Packaging

Always check the outside of the box for any signs of damage. If the packaging is damaged, the contents may have been exposed to moisture.

As mentioned earlier, moisture will impact the leavening agents. But more importantly, this could lead to mold growth.

Small holes in the packaging could also indicate enthusiastic pantry pests. In these circumstances, I highly recommend waving goodbye to your cake mix as you toss it in the garbage.

Changes in Appearance

sifting old cake mix to check for any issues

Before adding the wet ingredients to your cake mix, it’s time for a quick appearance check. Signs to look for include changes in color and texture of the cake mix – especially if it has become clumpy.

And don’t forget to keep an eye out for any signs of mold. Mold can be whitish, or it can be tinged with green or blue.

Sifting your cake mix will make it easier to see if there are any texture changes or the presence of mold.

Changes in Smell

If you notice an off odor or sour smell when opening the package or after adding the ‘wet’ ingredients, it’s probably best to throw the mix away. Some ingredients can turn rancid with age. Although they will not harm you, they will definitely impact the taste of your cake.

Why waste your cake calories on a bad-tasting cake?

Reviving Your Cake Mix

How to Use Old Cake Mix




Up to "best by" date

Normal use

Great taste

6 months past "best by" date

Normal use

Good to great taste

6-12 monts past "best by" date

Add baking powder, normal use

Does not taste as fresh. May start to get off-taste.

12-18 months past "best by" date

Add baking powder or use in alternate recipes

Likely tastes off or rancid. May not rise well.

18+ months past "best by" date

Use in alternate recipes

Likely tastes off or rancid. Unlikely to rise well.

If cake mix has mold, moisture, or signs of pests, discard immediately.

Leavening agents are the main reason cake mixes let us down after the “best by” date. So logically, adding more baking powder should help.

Unfortunately, it isn’t an exact science. The quantity you add depends on the amount of your cake mix and how ‘old’ your mix is.  

A five-year-old mix needs more help than a cake mix just a year old.

Although I can’t guarantee the results, one of these options will probably help you save that older box.

bowl of chocolate cake mix

Less Than 6 Months Past the “Best-by” Date

If less than 6 months have passed, you can happily go ahead and bake. You shouldn’t experience any quality issues. General Mills recommends extended “use-by” dates to Feeding America.

They advise that baking mixes can be used 6 months post the “best before” dates. I’m interpreting that as a thumbs up.

6 Months and Over the “Best-by” Date

As the leavening agents may have started to lose their potency, you will need to add that extra bit of punch in the form of baking powder.

The general proportions used by most cake manufacturers is 3 teaspoons of baking powder per 4 cups of cake mix, which is 3.75ml of baking powder per cup.

The average box of cake mix contains 4 cups. If you have a partial bag, measure the leftovers and calculate the proportions accordingly.

For mixes between 6 months and a year over the “best before date,” use ¾ teaspoon of baking powder.

With mixes over a year past the “best before date,” use 1½ teaspoons. For mixes that are above 2 years, use up to 3 teaspoons.

Short on Baking Powder?

Don’t worry. You can make your own with baking soda (sodium bicarbonate/bicarbonate of soda) and cream of tartar. Simply combine one teaspoon of baking soda with two teaspoons of cream of tartar which will give you 1 tablespoon of a baking powder equivalent.

When making your own baking powder equivalent, you will need to use it immediately as it doesn’t store well.

How Long Does Cake Mix Last in Mylar Bags?

Mylar bags are durable multi-layered bags suitable for long-term food storage. Layers of laminated food-grade plastic separate the food from the aluminum layer.

Mylar bags protect food from light, moisture, and oxygen. You know, all of the things that will degrade cake mix.

Most people who store cake mixes for their home food storage find that a cake mix will only last up to 1 year past the expiration date in a Mylar bag with an oxygen absorber.

Individual ingredients in the cake mix, like flour and sugar can be stored in a Mylar bag for up to 20 years. However shortening and baking powder in a cake mix have a much shorter shelf life.

Remember, the shelf life is based on the ingredient that degrades the fastest. It does not seem worth it to use an expensive Mylar bag to store cake mix when it does not last much longer.

Not Keen on Adding Baking Powder?

You might have added too much baking powder if you baked a cake with a sour aftertaste. Check out these expired cake mix recommendations if you prefer not to chance a sour cake.

Beware: Always cook cake mix. The Centers for Disease Control (CDC) has investigated cases of E. coli found in raw cake mix.

As with all baking, I recommend calibrating your oven for more accurate results. And using a kitchen scale for precision.

Here are a few favorite leftover cake mix recipe ideas.

  • Cake-Mix Cookies. Want to avoid a cake rise disaster? Then turn your boxed cake mix into cookie mix. Cake mix cookies are fabulous ways to use expired cake mix boxes.
  • Trifle. Bake the cake. Then break it into smallish bits and simply layer cake pieces with pudding and fruit. These are great when served in individual glasses.

    This also works well with ice cream, chocolate sauce, or caramel.

I wish you lots of luck with your baking. Put the kettle on, sit back, relax, and enjoy your homemade cake!

Did you like this post? Then let’s be social. FOLLOW ME on PINTEREST and INSTAGRAM to keep up with the latest tutorials, favorite recipes, and interesting happenings.