Pumping breast milk for your baby can be a great way to continue to breastfeed when you’re on the go. Plus, it can be a more convenient feeding option and a comfort during those times when you start to wonder: Is my baby getting enough breast milk? This is especially true if you are going back to work, or if your baby is going to daycare.

Below, we walk you through how to store breast milk and answer a few key questions that new mothers commonly have.

Breast milk storage guidelines

Your choice of container is important when it comes to storing breast milk. Use clean containers made of glass or hard plastic that doesn’t contain bisphenol A (BPA). You can also use a plastic liner designed for breast milk. We do not recommend using Ziploc bags because they could leak.

If you’re packaging breast milk for storage in the fridge or freezer, put it near the back where it will stay colder.

How much breast milk can I store?

How much breast milk you store is up to you but storing smaller amounts can help make sure it doesn’t go to waste. Storing breast milk in two or three-ounce batches can make the whole process easier. It’ll thaw faster, and you won’t have to worry about throwing much out if baby doesn’t eat it all.

How long can breast milk stay out at room temperature?

Freshly pumped breast milk is good for up to four hours at room temperature before you need to put it in the fridge, according to the Centers for Disease Control and Prevention (CDC).

How long can breast milk stay good in the fridge?

Proper storage in the back of the fridge can keep breast milk good for up to four days.

How long can breast milk stay good in the freezer?

Breast milk stays good in the freezer for up to 6-12 months but will be higher in quality the sooner it’s used. To freeze breast milk, leave an inch of space in the container for expansion.

If you don’t have access to a refrigerator or freezer, fresh breast milk can be stored in an insulated cooler with ice packs for up to one day.

How long is thawed breast milk good for?

Once frozen breast milk has been completely thawed, it’s good for one to two hours at room temperature or one day in the fridge.

To thaw frozen breast milk, either leave it in the fridge overnight, submerge it in warm water or run it under warm water from a faucet. Never use a microwave to thaw breast milk, as it can lower the nutritional quality and make the milk too hot for baby to eat safely. Once your baby has eaten from a batch of thawed breast milk, it has the potential for bacterial growth, so it should not be refrozen.

If you have questions, don’t hesitate to ask

Whether baby isn’t latching or you have a batch of breast milk that you’re unsure about, board-certified lactation consultants are here to help you. Many clinics or health plans have lactation consultants on hand to answer questions for moms, and you can reach them by calling in to a resource center.