How Long Does Breast Milk Last After Warming?

When it comes to our little ones, our parents are best friends with panic. So much so when it comes to the food they eat. Everything from pumping schedules to storage can be tricky if you have decided to breastfeed your baby.

No mama wants her liquid gold down the drain, and lots of questions like, “How long does breast milk last after warming?” Luckily for you, I am going to go in-depth to answer that question, so stay tuned!

How Long Does Breastmilk Last After Warming?

To be honest, I have heard this question so many times—half of which was me asking myself. When you read blogs and articles online, you will see a lot of answers. Some of those are accurate, and others are not.

If you ask me, I would say you should consult your lactation consultant or doctor for a personalized evaluation. Regardless, I will tell you what the experts say concerning the shelf life of warmed breast milk.

According to the Centers for Disease Control and Prevention, breastmilk that has been warmed or brought to room temperature should be used within two hours. And that means if your little one doesn’t eat it within that stipulated time, it needs to go out.

When frozen milk is brought to room temperature, it begins to lose its ability to fight bacteria. Frozen milk left to sit for 24 hours should not be left for more than 2 hours out of the fridge.

So, looking at the available information we have on using warmed milk, I would say breastmilk can be left to thaw for 24 hours outside the freezer. However, after those 24 hours or when warmed, it should be fed to your little one within two hours. (2)

I’ve seen moms that doubt this analysis, but I believe it’s better to be safe than sorry. It’s best to dispose of it rather than take any risks.

Where Can I Store My Warm Breast Milk?

Now that you understand how long warmed breastmilk lasts, you may be wondering where to keep it for such a short time. Well, the best place to store warmed milk would be in the refrigerator.

Since milk left out will become more susceptible to bacteria, you don’t want to leave it out too long. Ideally, warmed breastmilk should be stored for just 24 hours in the refrigerator, and that’s counting from when the milk was thawed. (3)

Can I Refrigerate The Leftover Warm Milk?

The best place to store leftover breastmilk is in the refrigerator. If you thawed the milk in the refrigerator, you can leave it stored there for an additional 24 hours.

Once the 24 hours have elapsed, you will need to get rid of the breastmilk. It’s best for your baby’s safety as the quality of the milk is questionable at that point.

Tips To Refrigerate Breastmilk

If you are going to store your warmed milk in the fridge, I suggest you store it in the same bag it was defrosted. You may also want to take off the initial date tag and change it to the date you put it back into the fridge. You could even add the exact time.

That way you ensure that the previously warmed milk doesn’t stay in the fridge for more than 24 hours. It’s not that it could make your baby sick but the prolonged storage time makes it lose its nutrients. So, it becomes of no use to your little one.

What If I Store My Leftover Warm Milk At Room Temperature?

Warm milk should be stirred at room temperature for not more than two hours. This is because bacteria can start to grow when it’s left out for a prolonged time. Bacteria from your baby’s mouth from the first feeding could also be present.

So, as I’ve been emphasizing it will be better to throw it out after two hours.

How To Store in Room Temperature, Refrigerator, and Freezer

The most crucial aspect of pumping breast milk for later use lies in storage. You have to be very careful to make the best out of it and not lose too many nutrients.

You may have to throw out your liquid gold if you don’t follow the accepted, healthy, and safe methods of pumping and storing your breast milk.

Let’s look at some ways to store your warmed milk.

  • Leave the milk, whether in a bottle or breastmilk bag, out on the kitchen counter after you have warmed it.
  • Place the milk in its initial storage container and leave it to sit at the back of the fridge.

I didn’t include the freezer guidelines because you should only freeze freshly expressed milk. As I stated earlier, breast milk cannot stay past 24 hours after it has been thawed and warmed.

How Long Can Breast Milk Store Room Temperature, Refrigerator, and Freezer

You have to be very careful when it comes to the storage of your pumped breast milk. Note that no matter the storage method, it is not ideal to leave warmed breast milk out for longer than 24 hours.

Below is how long breastmilk can last at room temperature, in the refrigerator, and in the freezer.

  • Room temperature: Warmed milk should not be left on the counter for more than 2 hours.
  • Refrigerator: You can store your liquid gold in the refrigerator for up to 24 hours after it has been thawed or warmed.
  • Freezer: Ideally, breast milk that has been warmed should not be frozen again. As soon as it exceeds 24 hours in the fridge, it should not be used.

What Should I Know about Re-Using Breast Milk?

As much as you would love to gauge the exact amount of milk your baby consumes at one feeding, it may be a little tough. This means that there will be times when you have leftovers from a feeding session. Don’t worry though, I’ll let you know what to do in such an instance.

How Long Can I keep the Unfinished breast milk?

I have discussed how to store warmed milk that hasn’t been used throughout this article. But what do you do if your little one doesn’t finish the expressed milk at a single feeding?

According to the Centers for Disease Control and Prevention, if your baby doesn’t finish the milk at feeding time, it can be reused for up to 2 hours afterward. Otherwise, you will have to throw it out. Consider pumping smaller amounts of breast milk to reduce wastage.

How can I prevent wasting breast milk?

No mom wants to see their liquid gold down the drain, and the good thing is that it doesn’t have to. You can arrange your pumping sessions in a way that allows you to express just the right amount of milk.

Here are some tips on preventing the wastage of your breast milk.

  • Freeze and thaw small amounts of breast milk.
  • Label each milk bottle or bag with the date you expressed it. So you can use the oldest bags first.
  • When returning to work, prepare small bottles for your caregiver at feeding times.
  • Practice paced feeding when feeding your little one with a bottle.
  • Nurse your baby or feed them with pumped milk on demand.


Breast milk that has been warmed can be used within the first two hours at room temperature and for up to 24 hours in the refrigerator. Regardless, whenever you doubt the quality of the milk, it’s best to throw it out.

Have you experienced any hiccups with warmed breast milk? Where do you store your thawed breastmilk before use? Drop your answers in the comment section. I would love to hear your thoughts.


  1. Centers for Disease Control and prevention, (2022, Jan 2022). Proper Storage and Preparation of Breast Milk,milk%20after%20it%20has%20thawed.
  1. The Academy of Breastfeeding medicine, (2017).  Human Milk Storage Information for Home Use For Full-Term Infants,milk%20after%20it%20has%20thawed.
  1. Donna Murray, RN, BSN, (2022, Aug 12). Verywell family. How to Thaw, Warm, and Use Frozen Breast Milk
  1. Centers for Disease Control and Prevention, (2021, Aug 10). Frequently Asked Questions,warming%20milk%20in%20smaller%20amounts.

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