Whether you formula feed or breastfeed, all moms can agree that throwing out a bottle is the worst. It's either money down the drain or, if you're a breastfeeding mama, time and hard work down the drain. You probably know that it's best to thaw only the amount of breast milk your baby actually needs, but how long does thawed breast milk really last? What if your baby doesn't finish their bottle? Do you really have to toss out six ounces of liquid gold?

According to the Centers for Disease Control and Prevention, it depends on where you're storing this thawed breast milk. If the breast milk is out at room temperature, up to 77 degrees Fahrenheit, it can last from six to eight hours. (Make sure to keep it covered.) If you're storing your thawed breast milk in an insulated cooler or bag, the CDC noted that it is safe for 24 hours and breast milk in the refrigerator is good for five days.

It's also important to remember that these numbers change once the baby has started to drink the bottle. Medela noted that milk that has been used for a feeding, meaning your baby's mouth has been in contact with the milk, should be used within one to two hours of feeding. Even if your baby only drank an ounce of the bottle, you can't keep it for the recommended six to eight hours. Once it's been an hour or two after you first offered the milk, it's time to toss it.


To eliminate waste, be sure to only thaw breast milk that you know you'll use. According to KellyMom, you can not refreeze thawed breast milk. Once it's been thawed, it's time to use it. Try to keep your breast milk stored in portions your baby will eat and thaw only one day's worth of breast milk at a time to make sure you aren't pouring too much of it down the drain.