Medela bottles with breast milk

The busy mom’s guide to safely and successfully storing breast milk

Building up a stash of breast milk gives you the ability to schedule date nights, Costco runs and anything else you need to do, with the peace of mind knowing your little one will have access to your breast milk when they need it. While pumping provides you with the ability to build up your supply, what should you do when you’re pumping away from home? To help you get started, we’re sharing the basics of successful breast milk storage, complete with real, mom-approved tips and tricks.

Breast Milk Storage Guidelines

How you choose to store your breast milk is completely up to you, and should follow whatever makes your life easier. In general, breast milk is relatively simple to work with. According to the Centers for Disease Control and Prevention, here are a few times to keep in mind when you’re storing your freshly expressed and frozen breast milk:

Freshly Expressed Breast Milk

  • At room temperature: up to 4 hours (or even up to 6 hours, according to the Mayo Clinic)
  • In the refrigerator: up to 4 days
  • In the freezer: between 6 to 12 months

Previously Frozen Breast Milk

  • At room temperature: up to 1 to 2 hours
  • In the refrigerator: up to 24 hours
  • In the freezer: Do not refreeze previously frozen breast milk

If your baby doesn’t finish the bottle in one feeding, you have about two more hours to use it, before it’s best to throw it out.

stored breast milk with dates

Bags or Bottles?

You’ll need to decide how you want to store your milk: in bags, bottles, or a combo of each. While the best option is what works for you, here are a few pros and cons you should know for each type of storage option.

Storage Bags

Storage bags are super reliable and almost never break (but remember to seal them all the way so your hard-earned liquid gold doesn’t leak!) and can save you extra space in your freezer or diaper bag because of their thin shape. Storage bags are not reusable, so they can tend to add up in price. Pro-tip: Freeze your bags lying flat so they can easily stack on top of each other, making milk organization a breeze. You also can buy them almost anywhere—hello, impromptu trip to Target!

frozen breast milk stacked in freezer


Storing your milk is bottles tends to be more cost-effective since they’re reusable. As a bonus, they’re more eco-friendly, since you can get multiple uses out of them. However, one downside is that bottles are a bit bulkier and can take up more space in cooler bags. If you plan to pump and use bottles for milk storage while on the go, make sure to bring at least four to six bottles with you so you’re fully stocked and can easily combine and transfer from pump to cooler.

Whether you plan to use bottles or bags, having a few extra bags on hand is always great when you need to pump in a pinch. Have a stash at home, in your purse, in the car, at the office—heck, keep a stash at the gym just in case you need them.

Storing Breast Milk on the Go

As a mom, you have enough on your plate, so worrying about keeping your milk fresh while out and about shouldn’t be one of them. Enjoy that last drink with your friends and don’t stress about your breast milk—pump and use those handy extra bags you stored in your purse and voilà! That liquid gold is still good at room temp for four more hours! Plus, unless you’re partying hard, who’s really out for that long anyway? #SleepIsGoals

When you get home, it’s always best to immediately store your breast milk in the fridge or freezer. If you plan to use it that night or within the next few days, a refrigerator is fine, otherwise freezer is best.

If you’re pumping in an office, advocate for a mini-fridge (or at least access to a fridge) where you can store your breast milk during the workday. If you need tips on transporting and storing breast milk here, we’ve got you covered.

For any on-the-go occasion, we recommend these products to make breast milk storage super manageable while you’re out living life:

YETI Cooler

YETI cooler

Why We Love It: This small-but-mighty cooler is just what moms need for a day (or night!) away. It’s compact enough to be ultra-portable, but strong enough to keep your precious liquid gold cold for hours. Plus, it’s resistant to mildew and punctures

Packit Bags

Packit bottles and coolers

Why We Love It: Packit’s Freezable Breastmilk and Formula Coolers are great because instead of containing ice packs that need to be refrozen, these lightweight and stylish coolers use a built-in freezable gel that keeps up to four 5-ounce bottles cold for hours. That means fewer parts for you to keep track of and more space in the freezer at home.

Lansinoh Milk Storage Bags

Lansinoh milk storage bags

Why We Love It: Lansinoh’s breast milk storage bags are known for being super sturdy and reliable, due in large part to their double Click ‘n’ Secure™ seal that helps prevent your precious milk from spilling or spoiling. Plus, you can pump directly into the bags, meaning one less step in your on-the-go pumping session. Just be sure to check that the bags are compatible before you try to pump with them, or buy a hundred in bulk.

Kiinde Twist Cooler Bag

Kiinde Twister cooler bag

Why We Love It: The slim pockets in the cooler keep your storage bags upright, so there’s no need to worry (or cry) over spilled milk. Plus, the design helps secure bags tight against the ice packs for maximum cooling. Every milk bag touches an ice pack, helping to keep your breast milk cool while you’re away or traveling with baby!

Looking for the perfect insurance-covered breast pump, or need to reorder some supplies? Check out our shop!