How Long Does Breast Milk Last After Warming? Mila's Keeper

How Long Does Breast Milk Last After Warming?

So how long is breast milk good for after warming? Here is what we know and how best to protect your liquid gold.

Our breast milk is known as "liquid gold" for a very valid reason. So it should go without saying that something this precious should be treated with the utmost care and attention. 

Key Takeaways

  • Warmed breast milk will typically need to be used within two hours of warming it.
  • Finding a reliable, plastic-free storage bottle for your breast milk is critical to safely storing your liquid gold.
  • You can thaw frozen breast milk in the fridge under running or in warm or hot water.
  • Expressed breast milk can be stored in a freezer for six months, in the fridge for four days, and at room temperature for four hours.

Each mama knows how important it is to put every drop of breast milk to good use! So knowing how to store properly and warm breast milk is the first step in avoiding the painful experience of tossing out any of your liquid gold. 

However, there are a lot of guidelines and factors to take into consideration in properly handling breast milk. We'll let you know everything you should remember when it comes to warming your breast milk!

See Related: 7 Foods To Avoid If You're Breastfeeding A Gassy Newborn

Tips For Storing Breast Milk The Right Way

Mamas have a lot to worry about. Though motherhood is a gratifying and enriching experience, it doesn't come without its challenges.

Every mother knows breast milk is priceless and the best way to give their little ones the nutrition they need for a healthy start in life. So when you store breast milk, it's essential to ensure you're doing it safely and correctly.

But we know that, especially for first-time mamas, keeping track of all the breast milk storage guidelines can be daunting and overwhelming. At the same time, you must be particular about what you feed your baby!

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The key to properly storing breastmilk starts with finding the correct storage container. After all, isn't that what will be holding your liquid gold?

We thought the same thing. That's why here at Mila's Keeper, we designed our iconic and innovative glass breast milk storage containers, perfect for giving each and every mama the peace of mind she deserves when it comes to breast milk storage.

Plus, the stylish design of these breast milk bottles also allows you to walk proudly with your liquid gold, knowing that you are capable of anything as a mama!

Everything that comes into contact with your baby's milk needs to be free of anything potentially harmful to the quality of your milk. So not only are our bottles designed with medical-grade borosilicate glass but they're also made with no plastics and no toxins.

And last (but definitely not least), the powerful and unique materials of these bottles allow them to safely withstand the cold of a deep freezer and the heat of a bottle warmer or even a microwave.

We didn't miss anything when we designed our products. Because, as mamas, we know that covering every single base is something that all mothers pay attention to!

The Best Ways To Thaw Frozen Breast Milk

Breast milk is a valuable good that can't be treated as something disposable. Every drop is priceless - and as mamas, we don't want it to ever go to waste.

You can only keep breast milk at room temperature for up to four hours, and that's not that long in the grand scheme of things. That's why many of us choose to freeze milk to allow us to prolong its lifetime.

In fact, breast milk can be stored in a deep freezer for six to nine months. And bumping four hours up to even six months can lend many of us moms a helping hand!

Either way, eventually you'll need to thaw any breast milk that was frozen so you can feed it to your little one. And though freezing milk can be somewhat straightforward, thawing can be a tad more complicated.

Wondering about the best ways to thaw breast milk safely? We'll let you know the most popular ways to bring frozen milk back to room temperature!

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Method 1: In The Fridge

When it comes time to thaw breast milk, it's important to thaw the oldest breast milk first. You should always remember, first in, first out! Along with this, it's also a good idea to always label your milk with the date you place it in the freezer.

So step one of thawing breast milk will always start with identifying the oldest portion of breast milk. And if you choose to thaw your frozen liquid gold in the refrigerator, it can stay there for up to a full day before feeding it to your little one.

Per CDC standards, thawed breast milk that was previously frozen can stay in a fridge for 24 hours. However, these 24 hours start ticking after the milk is completely thawed, not once it's been removed from the freezer.

Not only is the fridge a popular place for thawing breast milk. But it's also a good location to store freshly expressed breast milk

Pumped or expressed milk can be stored in the fridge for up to four days. So sometimes, you don't even need to worry about freezing your milk if you plan to use it within these four days!

Method 2: With Standing Or Running Warm Water

If you want to forego the refrigerator, you can also use warm water to thaw frozen milk. You can either do this by placing frozen milk in a container of warm or lukewarm water or by holding it under warm, running water.

And lastly, always keep in mind you should never refreeze thawed breast milk.

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Bonus: Is It Safe To Drink Alcohol While Breastfeeding?

How Long Is Breast Milk Good For After Warming?

It's a common practice for mamas to heat breast milk before feeding it to their little ones. However, keep in mind it's not necessary to do so. Your milk can be safely served to your little one at room temperature or even still cold!

Breast milk has plenty of guidelines to ensure its safe consumption for your baby. Everything from freezing, cooling, thawing, heating, and storing human milk has several pieces of advice and recommendations.

Many questions that mamas ask typically regard warmed breast milk. We'll let you in on all the details you should know!

How Long Can Breast Milk Sit At Room Temperature?

When it comes to handling breast milk, there's a lot to keep in mind. We know freshly expressed milk can be kept in a freezer for six months and in the fridge for four days.

As far as pumped or expressed breast milk, it can sit out on the counter for up to four hours. But any thawed breast milk has a much stricter time frame it needs to abide by.

Once brought to room temperature, previously frozen breast milk can stay at these conditions for one to two hours, per CDC standards. And previously refrigerated milk can stay at room temperature for up to 24 hours.

So then how long is warmed up breast milk good for? For warm milk, things can be a little different. The life of warmed milk can last for two hours, according to the Academy of Breastfeeding Medicine.

Remember that you shouldn't microwave breast milk. Not only does this break down the healthy nutrients essential for your little one, but it also can create hot spots that can burn your baby's mouth!

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Signs Of Milk Gone Bad

It's a good idea to still know how to recognize spoiled milk to avoid feeding it to your little one. Luckily, there are tell-tale signs that will immediately alert you to the possibility of bad milk.

The first will be that the breast milk may have a foul odor. This will be highly noticeable and hard to miss.

Secondly, the milk may be separated, and the chunky, fatty regions may not mix with the rest of the contents.

And the last sign of bad milk is a musty and unnatural taste.

Throwing out breast milk is painful for any mama. But as nursing mothers, what's truly most important is keeping our babies healthy and safe.

So don't risk it! If it's likely or probable that any of your milk has gone bad, throw it out. It may feel terrible at the moment, but knowing you're only feeding your baby the safest milk will give you peace of mind in the long run.

What About Leftover Breast Milk?

We've all had those moments when our little one doesn't finish the milk in the baby bottle. And in this case, it's essential to know what to do with any leftover milk.

It's commonly agreed upon that any breast milk remaining after feeding your little one should be used within the next two hours. Any unused milk after that should be thrown out.

This is where breast milk storage best practices can come in handy. Store breast milk in baby bottles or storage bags in small amounts to ensure you won't have extra milk left over after a feeding. 

For example, storing only two to four ounces of milk in each storage bag or container can reduce the likelihood that there will be too much for your baby to have in one sitting.


We know that all these numbers, timeframes, and guidelines might seem like a lot. We've also been there before as mamas ourselves! But keeping in mind these vital pieces of information is essential for keeping your little one happy and healthy.

Keep Reading: Does Breastfeeding Really Burn That Many Calories?


A female-designed and female-run company, Mila's Keeper is on a mission to empower women to thrive during their breastfeeding journey by offering reusable, eco-friendly breast milk storage solutions for their day-to-day needs. Get the latest tips and info on Mila's Keeper products by following us on Facebook, Twitter, Instagram, Pinterest, and LinkedIn

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