How Long Buttercream Lasts in the Refrigerator and How to Store It Properly

Buttercream stays fresh in the refrigerator for two to three weeks when stored in an airtight container

Buttercream is a stable frosting because of its high fat content—butter and powdered sugar are the main ingredients, and both resist spoilage. The refrigerator slows any moisture loss and keeps the buttercream at a consistent temperature, which prevents the texture from becoming grainy or separating. A sealed container is essential because buttercream absorbs odors and flavors from your fridge, and it can pick up moisture from the air that makes it weep or become sticky.

The exact timeline depends on what's in your buttercream. American buttercream (butter, powdered sugar, milk or cream, and vanilla) lasts the full two to three weeks. Swiss or Italian meringue buttercream, which contains egg whites, is safe for the same period because the eggs are cooked during preparation. Cream cheese buttercream lasts slightly shorter—about one to two weeks—because cream cheese breaks down faster than pure butter. Dairy-free versions made with shortening or coconut oil follow the same two to three week window as American buttercream.

Key Takeaways

• Store buttercream in an airtight container on a refrigerator shelf (not the door) to keep it fresh for two to three weeks.
• Let buttercream come to room temperature for 30 minutes before using it, so it spreads smoothly without tearing the cake.
• Cream cheese buttercream lasts one to two weeks because cream cheese spoils faster than butter alone.
• Buttercream absorbs odors from your fridge, so keep it sealed and away from strong-smelling foods like onions or fish.
• Frosted cakes can sit at room temperature for up to two days, but store unfrosted cakes and buttercream separately for longer storage.

The right container keeps buttercream fresh and prevents odor absorption

Use a container with a tight-sealing lid—a plastic storage container, glass container with a snap-on lid, or even a resealable plastic bag pressed flat to remove excess air. The seal matters more than the material. Buttercream left uncovered or loosely covered will absorb the smell of garlic, onions, fish, or whatever else is in your fridge within hours, and that flavor will transfer to your cake.

If you're storing a frosted cake, keep the container on a middle or lower shelf rather than the door. The door is the warmest part of the refrigerator because it opens and closes constantly, and temperature swings can cause the frosting to soften, crack, or develop a grainy texture. A middle shelf maintains a steadier temperature, usually between 35 and 40 degrees Fahrenheit.

Bring buttercream to room temperature before spreading it on cake

Cold buttercream is stiff and difficult to spread without tearing the cake layer underneath. Remove the container from the refrigerator and let it sit on the counter for 20 to 30 minutes. Stir it gently with a spatula or whisk—this helps it warm evenly and restores the smooth, creamy texture. If you're in a hurry, you can microwave it in 5-second bursts, stirring between each burst, but this risks overheating and separating the frosting.

Test the consistency by pressing your finger into the frosting. It should feel soft enough to spread easily but still hold its shape. If it's still too stiff, give it another 10 minutes. If it becomes too soft or starts to look oily, it's overheated—refrigerate it for 10 minutes and try again.

Frosted cakes have a different timeline than plain buttercream

A cake frosted with buttercream can sit at room temperature for up to two days without spoiling, as long as your kitchen is not unusually warm. The buttercream layer acts as a seal that slows moisture loss from the cake and protects it from dust and bacteria. After two days, move the frosted cake to the refrigerator to extend its life to four to five days total.

If you want to store a cake longer, separate the components. Wrap unfrosted cake layers in plastic wrap and store them in an airtight container in the refrigerator for up to five days, or freeze them for up to three months. Store the buttercream in its own sealed container. Assemble and frost the cake the day you plan to serve it, or frost it the day before and refrigerate the finished cake.

Freezing buttercream extends storage to three months

Buttercream freezes well because its high fat content prevents ice crystals from forming and damaging the texture. Spoon it into an airtight container, leaving about half an inch of headspace at the top (buttercream expands slightly as it freezes). Label the container with the date and type of buttercream. It will keep for up to three months in the freezer.

Thaw frozen buttercream in the refrigerator overnight, then bring it to room temperature on the counter for 20 to 30 minutes before using it. Stir it well to restore the smooth texture. Do not thaw buttercream at room temperature or in the microwave, because uneven thawing can cause it to separate or become grainy.

Signs that buttercream has gone bad and should be discarded

Buttercream that has spoiled will show clear signs. Look for mold, which appears as fuzzy spots or discoloration on the surface. Smell the frosting—if it smells sour, rancid, or off in any way, discard it. A sour smell means bacteria or mold has begun to grow, even if you cannot see it. Taste is not a reliable test, so do not taste buttercream you suspect has spoiled.

Separation—where the frosting looks oily or watery and the ingredients are no longer blended—is not always a sign of spoilage, but it means the texture is compromised and the frosting may not spread or hold its shape on a cake. Discard it or try to save it by refrigerating it for an hour and then beating it with a mixer on medium speed for a minute or two. If beating does not restore the texture, discard it.

Cream cheese buttercream needs extra care because of the dairy content

Cream cheese buttercream contains both butter and cream cheese, and cream cheese is more perishable than butter alone. Store it in the coldest part of your refrigerator—usually the back of a middle shelf—in a sealed container. It will last one to two weeks, which is shorter than American buttercream. Do not leave cream cheese buttercream at room temperature for more than two hours, or bacteria can begin to multiply.

Cream cheese buttercream does not freeze as smoothly as American buttercream because the cream cheese can separate during thawing. If you do freeze it, thaw it slowly in the refrigerator and beat it with a mixer to restore the texture. For best results, make cream cheese buttercream fresh or store it in the refrigerator rather than the freezer.

Frequently Asked Questions

Can I frost a cake and then refrigerate it overnight?

Yes. A frosted cake can be refrigerated for up to four to five days in an airtight container or covered with plastic wrap. Let it come to room temperature for 30 minutes before serving so the frosting is soft and the cake is not cold. If the frosting hardens in the fridge, you can gently warm it with a warm knife or spatula before serving.

Does buttercream go bad if I leave it on the counter?

Buttercream can sit at room temperature for up to two days without spoiling, but it will soften and may begin to separate if your kitchen is warm. After two days, refrigerate it. Do not leave buttercream at room temperature for more than eight hours if your kitchen is above 72 degrees Fahrenheit.

Why does my buttercream smell like the food next to it in the fridge?

Buttercream absorbs odors because it is mostly fat, and fat readily absorbs and holds flavors and smells from the air. Always store it in a sealed, airtight container away from strong-smelling foods like onions, garlic, fish, or leftover curry. Keep it on a shelf away from the produce drawer, where ethylene gas from ripening fruits can also affect the flavor.

Can I use buttercream that has been in the fridge for a month?

No. Buttercream is safe for two to three weeks, and after that mold or bacteria may have begun to grow, even if you cannot see or smell it. If you need buttercream beyond three weeks, freeze it instead. Frozen buttercream lasts up to three months and is safer than refrigerated buttercream that has been stored too long.

What's the difference between storing buttercream and storing a frosted cake?

Plain buttercream lasts two to three weeks in the refrigerator. A frosted cake lasts four to five days in the refrigerator because the cake itself can dry out or develop mold. If you want longer storage, freeze the unfrosted cake layers and the buttercream separately, then assemble them when you are ready to serve.