If you're new to the world of pumping breastmilk, navigating the ins and outs of proper storage can feel daunting. But fear not! We're here to walk you through the essential steps to ensure your breastmilk remains safe for your baby.

Please note that all the information provided in this guide is based on the current Canadian government recommendations.

Breastmilk Storage Guidelines

Safe Breastmilk Storage

After pumping, it's crucial to store your milk in a clean container. It is advised to use sterile milk storage bags or clean food-grade containers made of glass or plastic with tightly fitting lids. Avoid containers marked with recycle symbol number seven, as they may contain BPA. Opt for containers specifically designed for storing breastmilk, such as glass mason jars or specialized breast milk chiller bottles. Remember to label each container with the date that it was pumped!

Tip: When breastmilk is refrigerated, it separates into 2 different layers; you can stir or shake the milk to reincorporate the separated fat. Shaking breastmilk does not damage it!

Breastmilk Shelf Life

Freshly expressed breastmilk can be stored at room temperature [16 °C (60 °F) to 25 °C (85 °F)] for up to four hours. If the milk was collected under clean conditions, such as by using properly washed hands and properly cleaned pump parts and containers, milk may be kept at room temperature for 6 to 8 hours. It can be kept fresh in a cooler with frozen gel packs [15 °C (59 °F)] for 24 hours, in the refrigerator [4 °C (39 °F)] for up to five days and in the freezer [-18 °C (0 °F)] for up to six months. Avoid storing breastmilk in the refrigerator or freezer door, as this area experiences the most temperature fluctuations.

Tips for Freezing Breastmilk

Freeze breastmilk as soon as you know you won't use it within the first four days to preserve its quality, in small portions (2 to 4 ounces) initially to gauge your baby's needs. Leave about an inch of space at the top of containers to accommodate milk expansion during freezing. Contrary to common belief, air bubbles in frozen milk do not cause gas in babies.

Defrosting and Heating Frozen Breastmilk

When defrosting frozen milk, use the oldest dated milk first to maintain quality. Never refreeze thawed breastmilk; use it within 24 hours of complete thawing. Thaw milk slowly in the refrigerator overnight or by running warm water over the storage container until the milk becomes slushy. Then warm the breastmilk by setting it in lukewarm water for 20 minutes. Avoid microwaving, as it can create hot spots that can burn your baby’s mouth and throat and destroys nutrients. Test the milk temperature before feeding by placing a few drops on your wrist. Once warmed or brought to room temperature, breastmilk should be used within two hours.

Remember, each baby may have different preferences regarding milk temperature, but it doesn't affect the nutritional quality of the milk. 

Reheat Breastmilk


Properly handling and storing breastmilk is essential for your baby's health and safety. To help you stay on track, we've compiled a handy checklist with the key details outlined above. Keep it handy as a quick reference guide as you embark on your breastfeeding journey!

Safe Breastmilk Handling
March 04, 2024