Safe Storage Times of Expressed milk for Healthy Babies

Freshly Expressed:

  • At room temperature: 6 hours
  •  In the refrigerator: 8 days
  • Deep Freeze: Up to 12 months

Thawed milk in the refrigerator but not warmed:

  • at room temperature: 4 hours
  • in refrigerator: 24 hours
  • Do not refreeze

Thawed at room temperature and then warmed: 

  • for completion of feed then discard
  • in refrigerator:4 hours
  • Do not refreeze

Discard any milk left after infant has completed feed

Remember to transport your expressed breast milk (or formula) in a cooler bag with an ice pack on hot summer days.  Outside temperatures are much hotter than room temperature. Freshly expressed milk can be stored with gel or freezer packs for 24 hours in cooler.

Containers for storage at home:

  • Glass or BPA-free hard plastic
  • need to be clean, but do not need to be sterile.
  • Small jars and bottles with lids, such as a glass jar.
  • Pre-sterilized, sturdy bags meant for human milk storage that can be tightly sealed.
  • Do not use baby bottle liners as they may break
  • Mark the date on your container.  Use older milk first
  • Store breastmilk in small amounts
  • Do not store milk in the door of your refrigerator.  Store the milk near the back of the refrigerator where the temperature is the coldest
  • You can add fresh cooled breastmilk (to be frozen) to milk that is already frozen and return it to the freezer. 
  • Label the container with the date of the first pumping
  • When freezing breastmilk, leave a 1.5 cm (1/2 inch) space at the top of the container
  • Thaw frozen breastmilk for 8 – 12 hours in the refrigerator, or under warm water
  • Throw away breastmilk that has been thawed for more than 24 hours
  • Do not refreeze breastmilk
  • Breastmilk should never be heated in a microwave

Cleaning instructions: 

  • Rinse container in cool water.
  • Wash container in hot soapy water, rinse in warm water and allow to air dry.
  • If soap is not available then place items in a pot, cover with water and bring to a boil. Boil for 5 minutes and
    remove items with clean tongs.
  • Dry containers should be covered and stored in a dry, clean area away from food.
  • Throw out any milk your baby does not finish at a feeding


updated Oct. 2020 from: 
Breastfeeding Protocol: Expressing, Collecting, and Storing of Human Milk