Collecting and Storing Pumped Milk

  • Wash your hands with soap and water and find a comfortable place to sit.
  • To help your milk let down, gently massage your breasts in circles, or stroke towards the nipple.
  • Collect and store milk in clean, glass or hard plastic food grade (BPA free) storage containers or bags.
  • Pump for 10-15 minutes, or until you have obtained the desired amount of milk. If pumping hurts, turn the pressure down or try a different size breast shield.
  • Seal containers well. If freezing milk, leave space at the top of the container for frozen milk to expand.

Most moms store from 2-5 ounces (60-150 cc) in a container. This is how much most babies older than one month of age eat in one feeding. You may combine milk from both breasts into one storage container. If you add newly pumped milk to cold or frozen milk, cool the new milk first. 

How long can you store pumped milk? Breast milk does not spoil easily. Below are suggested guidelines from the Academy of Breastfeeding Medicine, based upon current research (see for the entire protocol). Frozen breastmilk does not become “dangerous” if it is stored longer than these guidelines, however, its nutritional and protective factors decrease with time. Do not use milk stored longer than 12 months as the only source of nutrition for your baby.

Feed your baby fresh (never frozen) milk if it is available.  To defrost frozen milk: place container of milk in the refrigerator overnight, or in a pan of warm water. Do not microwave breast milk to defrost or warm. Defrosted milk should not be re-frozen and is good for up to 24 hours if stored in the refrigerator. It is normal for defrosted milk to separate. Swirl gently to blend milk. Breast milk should not smell or taste soapy, rancid or sour. If you feel that your expressed breast milk has an unusual odor, please see our information on Unusual Odors in Pumped Breast Milk for additional guidance.

If your baby does not finish a bottle of pumped milk, there is no research on how long the milk may be kept, or whether it can be refrozen. Most people are comfortable storing the unfinished milk in the refrigerator and having baby finish the bottle within 4 hours. Avoid offering larger amounts of milk in a bottle to avoid wasting milk.

For current Nebraska DHHS Breastmilk Storage Guidelines for in-home and day care centers, please visit our website:


Reviewed: copyright December 2017