How to donate breast milk to a milk bank

By Kaya Thomas, founder of Milk Diary

If you have more breast milk than your baby needs, a nonprofit milk bank can turn it into food for babies who need it most, often premature and sick babies in hospital. A premature baby may take only about an ounce at a feeding, so even a freezer drawer of milk goes a long way. Nonprofit milk banks in North America gave out a record 13 million ounces of donor milk in 2025, and they rely on parents with milk to spare.

This guide covers who can donate, how the screening works, how to store and send your milk, and what happens to it after. It's not medical advice, and every milk bank sets its own rules, so check the details with the bank you choose.

Looking for a milk bank? Use the milk bank finder to see the nearest ones to you, with links to sign up as a donor.

Who can donate breast milk?

Each milk bank has its own criteria, but they usually look for donors who:

Parents whose baby has died can donate too, and many banks have no minimum for bereaved donors. Surrogates and gestational carriers are often welcome as well.

How to become a milk donor

The steps are similar at most nonprofit milk banks:

  1. Contact a milk bank. Find one with the milk bank finder, then call or fill in its online donor form. It doesn't have to be in your state or province, since many banks work across a whole region.
  2. Do a phone interview. A donor coordinator asks about your health, lifestyle and medications.
  3. Fill in a health history form.
  4. Get your provider's OK. The bank may ask your doctor, midwife or your baby's pediatrician to confirm that donating is fine for you and your baby.
  5. Get a blood test. The bank arranges it at a lab near you, and you don't pay for it.
  6. Send or drop off your milk. Once you're approved, the bank tells you how to pack your milk. Most ship it overnight in a cooler at no cost to you, and some have drop-off depots at hospitals and clinics.

You don't pay anything to donate. Nonprofit milk banks don't pay donors either.

How to store breast milk for donation

Milk banks need to know your milk was handled safely. Before you start freezing milk to donate, ask your bank about:

The basics from the CDC apply too: wash your hands before pumping, keep your pump parts clean, leave space at the top of each bag because milk expands as it freezes, and keep milk in the back of the freezer, where it's coldest.

What happens to donated milk?

Milk banks screen every donor, then pool milk from several donors, pasteurize it to kill bacteria and viruses, and test it before it goes out. Most of it goes to hospitals for premature and medically fragile babies, and some goes to families at home.

For premature babies, donor milk lowers the risk of necrotizing enterocolitis (NEC), a serious bowel disease. The American Academy of Pediatrics recommends pasteurized donor milk from a milk bank for high-risk babies when their own parent's milk isn't available.

Sharing milk directly with another family

Not everyone can donate to a milk bank. You might not reach the bank's minimum, live far from one, or not meet one of its screening rules. You can still share your milk directly with a family who needs it. Lots of families rely on peer-to-peer milk sharing, including parents who can't make enough milk, adoptive and foster parents, and parents who've had breast cancer.

Share the Drop is an app that matches donors with families nearby who need milk. You create a profile, message families in the app, and meet in person to hand off your milk. It's free for donors and commerce-free, so no one pays for milk, and you can choose to share your health or test results with families.

Milk shared directly isn't screened and pasteurized the way milk bank milk is, so families usually ask donors about their health, medications and recent tests. Milk banks mostly supply hospitals, where pasteurized donor milk goes to the most fragile babies. If you're receiving milk, talk with your baby's pediatrician about what's right for your baby.

If you're donating because of an oversupply

Having milk to spare is a good reason to donate, but pumping more to build up a donation tells your body to make even more milk. If you're managing an oversupply, or it's uncomfortable, talk to your lactation consultant before you add pumping sessions just to donate.

Tracking your donation milk in Milk Diary

Milk banks ask when each bag was pumped and how it was stored. Milk Diary keeps that in one place:

Feeding your baby donor milk? Milk Diary tracks that too. See how much donor milk you have in storage, and mark donor milk right in a bottle feed so you know what your baby had.

Your data stays on your device and in your own iCloud. We can't see it, and there's no account to create.

Download Milk Diary free on the App Store

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