Storing Breast Milk at Room Temperature

Guidelines for Fresh, Refrigerated, and Frozen Breast Milk

Bottle of breast milk on a counter.
How long can breast milk stay out at room temperature?. Image Source/Getty Images

How Long Can Breast Milk Be Left Out At Room Temperature?

For healthy full-term infants, here are the guidelines for storing breast milk at room temperature.

  • Freshly expressed breast milk can be left out at room temperature (Up To 77 degrees F or 25 degrees C) for approximately 5 to 8 hours.
  • Breast milk that has been in the refrigerator can be placed at room temperature for up to 4 hours.
  • Frozen breast milk that has been thawed in the refrigerator, but NOT yet warmed up can remain at room temperature for up to 4 hours.
  • Frozen breast milk taken directly from the freezer should NOT be stored or defrosted at room temperature.
  • Frozen breast milk that has been defrosted AND warmed up should be used immediately or placed in the refrigerator. It should NOT be stored at room temperature for any length of time.

Breast Milk and the Growth of Bacteria

Bacteria is all around. It's on your hands, on the skin around your breasts, and on the parts of your breast pump. When you express your breast milk, some of that bacteria gets into the milk. But, don't worry, when you store your breast milk safely, this small amount of bacteria will not harm a healthy, full-term child.

Breast milk contains antibacterial and immune properties that can prevent bacteria from growing inside of it for many hours. However, the longer it is left out, the more time the bacteria has to multiply. Temperature also plays a significant role in the growth of bacteria.

The higher the temperature of the room, the faster the bacteria can grow. So, to be safe, you should ideally use room temperature breast milk within 4 to 5 hours. But, if necessary, you could extend that time up to about 8 hours (preferably in a cooler room). After 8 hours out at room temperature, the bacteria can grow to unsafe levels.

While some sources state that due to the antibacterial properties found in human milk, it can remain at room temperature for as long as 10 to 12 hours, that is generally not the accepted recommendation. The Centers for Disease Control and Prevention (CDC) and the Academy of Breastfeeding Medicine (ABM) recommend that breast milk should not stay out at room temperature for longer than 6 to 8 hours. The American Academy of Pediatrics (AAP) recommends no longer than 4 hours.

Storing Breast Milk for Premature Babies or Babies With Health Issues

These guidelines do not apply to premature infants or children that do not have healthy immune systems. The bacterial growth that occurs in breast milk that is left out at room temperature can be dangerous to children who at a higher risk of infection. In general, breast milk expressed for premature or hospitalized infants should be used within one hour or refrigerated. Discuss the recommended storage guidelines for your situation with your child's health care providers.

Tips for Storing Breast Milk at Room Temperature

  • The temperature of the room should not be over 77 degrees F or 25 degrees C. The cooler the room, the better.
  • If the room temperature is greater than 77 degrees F (25 degrees C), do not leave your breast milk out all. Place it in the refrigerator or an insulated cooler with ice packs immediately.
  • Once you collect your breast milk in the storage container, put a top or cap onto the breast milk storage bottle or seal the storage bag.
  • Place a cold towel over the storage container to keep the milk cooler.
  • Keep your breast milk away heat, windows, or areas that expose it to direct sunlight.



Academy of Breastfeeding Medicine Protocol Committee. ABM clinical protocol# 8: Human milk storage information for home use for full-term infants. Original protocol March 2004; revision# 1 March 2010. Breastfeeding Medicine. 2010;5(3).

American Academy of Pediatrics. Breastfeeding Initiatives. FAQs. Accessed March 15, 2015:

Centers For Disease Control and Prevention. Proper Handling and Storage of Human Milk. 2010. Accessed March 1, 2015:

Lawrence, Ruth A., MD, Lawrence, Robert M., MD. Breastfeeding A Guide For The Medical Profession Eighth Edition. Elsevier Health Sciences. 2015.

Newman, Jack, MD, Pitman, Theresa. The Ultimate Breastfeeding Book of Answers. Three Rivers Press. New York. 2006.

Riordan, J., and Wambach, K. Breastfeeding and Human Lactation Fourth Edition. Jones and Bartlett Learning. 2014.

Continue Reading