How to store and organize breastmilk

How to store and organize breastmilk

How to store and organize breastmilk

Congratulations! You’ve built up a stash of breastmilk. You feel amazing that your baby has a supply of liquid gold tucked away for date night (whenever that may be!) or when your partner takes on nighttime feeding duty. what do you do with it? A few bottles of milk for the following day can be neatly tucked into the back of your fridge, but when you start getting bags upon bags, you need a plan of action to keep you and your baby’s hard-earned breastmilk safe until it’s time to drink. 

Storing in the fridge

Let’s touch on a few basics of milk storage for the fridge. Even if you have a couple of bottles, that’s precious liquid! Handle with care.  

How to store?

Pumped milk should be stored in the bottle it was pumped in or a sterile milk bag. You can use clean, food-grade containers made of glass or plastic with tight-fitting lids for storage, but don’t use any plastics with the recycle symbol 7. (Why this type? They may contain BPAs, which are harmful to both babies and mamas alike.) 

Moreover, only use bags expressly intended for milk storage. No substitutions!

Milk should not be stored in the refrigerator door, as temperatures fluctuate there. Instead, store at the back of the fridge where the milk will stay consistently cool. 

How long to keep? 

Freshly pumped milk can be stored in a fridge for up to 4 days. On the other hand, dethawed milk can be stored in a fridge for up to one day. 

Storing in the freezer

How to store?

Once you start accumulating your stash, you’ll need to move some of the milk to the freezer, considering that freshly pumped milk can only stay in the fridge for 4 days. If milk is stored in bottles or other food-grade containers, transfer to milk storage bags. Leave an inch of space or more in the milk storage bag — breastmilk expands when frozen. 

Freeze your milk flat and label

You’ll get more mileage, spacewise, if you freeze milk laying down. Why? It will evenly freeze instead of with bumps and lumps. To do this, try the sheet pan trick — it makes it easy to batch freeze and ensure flatness. 

Also, make sure to freeze your milk in baby-sized batches of 2-4 ounces. It’s easier to thaw out a bit more milk than deal with leftover milk. 

Once milk is frozen, don’t forget to label it! You can also include any other relevant information, like if you drank any caffeinated beverages, ate any potentially allergenic foods, whatever you think you might impact your baby. 

Freeze in ice cube trays

We love this ingenious method of divvying up perfect portions of breastmilk with little effort. Each cube holds about one ounce, so it’s easy to crack out a few cubes, thaw and feed. (Bonus: you can quickly pop one of these cubes in a mesh feeder to soothe sore gums for a teething little.)

If you’re not planning on building a large stash, then this method can work especially well for you; it involves little extra equipment or storage considerations. However, if you accumulate more than a few trays, it might get unwieldy. 

How long to keep it?

As per the CDC’s recommendations, you can freeze breastmilk safely between 6-12 months, with 6 months being ideal and 12 months being acceptable. Your freezer should be set at 0° Fahrenheit or lower.  Yes, technically, frozen food can keep indefinitely, but it’s better to be extra cautious and just let it go. (Pun mostly not intended.)

Storing in a deep freezer

When it comes to storing your breast milk in a deep freezer, the same practices apply as your regular kitchen freezer. What’s more important to consider for deep freezers is how you’re organizing your milk. After all, no mama wants an avalanche of frozen breast milk at 2am. 

(Note, this tips can apply also for your kitchen fridge if that is your primary storage location.)

Store in clear freezer bags

Storing your milk by date? Diet? Some other lifestyle features? Storing your milk in clear freezer bags makes it easy to group and label your breastmilk stash. 

Store in bins

Whether you're using an official breast milk organizer or an adorable bin from Target, this method helps you save space in your freezer. And when you're a busy mom, it's great to be able to just reach into the deep freezer and pluck out a few bags. Accessibility for the win!

Time for milkies!

Ready to use your breastmilk? Here are a few tips you should know as you thaw, warm, and use the milk. 


You should always thaw milk either in your fridge or in cool water. Don’t leave it out at room temperature to thaw or thaw it in the microwave or boiling water. Once previously frozen milk has thawed, you can keep it at room temperature for no more than 2 hours or in the fridge for up to 24 hours. 

Remember: once milk is thawed, it’s thawed. Don’t refreeze!


Just as in thawing, don’t warm up the breastmilk in the microwave or in boiling water. In fact, you don’t need to warm it up at all — cool or cold breastmilk is totally fine for your baby to drink. If you do choose to warm up your milk, place under warm running water until the milk feels warm or use a bottle warmer. Swirl the bottle to incorporate fat, never shake. 

Using the milk

Feed your baby with the bottle of their preference. A typically feeding should be between 2-4 ounces, though this will vary by age and needs of baby. (Babies with issues with latch, mamas who are relactating, or a number of other scenarios, you may be advised to use a supplemental nursing system to deliver enough milk for a feed.) 

If there is leftover milk, you can keep for up to 2 hours at room temperature after the feeding. After the 2 hours is up, discard. (Crafty, resourceful mamas, you can save the milk for milk baths or breastmilk lotion or soap!)

What methods of storing and organizing breastmilk have worked well for you?

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