How long breast milk keeps depends on temperature and whether it is fresh, thawed or already used for a feed. Each has a different time limit. Our guide follows CDC advice for storing milk at home for healthy, full-term babies.
Sources: CDC
Fresh milk: location, temperature, time
- Room
- ≤ 25 °C / 77 °F · 4 hFreshly expressed, maximum
- Refrigerator
- ≤ 4 °C / 40 °F · 4 daysFreshly expressed, maximum
- Freezer
- ≤ −18 °C / 0 °F6 months best; up to 12 acceptable
Prepare the container and label
Use suitable clean breast milk containers and label them with the expression date. Small portions can help avoid thawing more than needed. An app entry can supplement the label, but it does not replace it.
Sources: CDC
How long does breast milk last in the fridge?
The table uses CDC limits: freshly expressed milk for up to four hours at 25 °C / 77 °F or cooler, and up to four days refrigerated at 4 °C / 40 °F or cooler. At −18 °C / 0 °F or colder, about six months is best; up to twelve months is acceptable under CDC guidance. Temperature and uninterrupted cooling matter.
Other health authorities may use different limits. Do not combine the longest times from different tables. Ask your care team when storage conditions are uncertain or you have an individual care plan.
Sources: CDC
Thawing changes the time limit
Under CDC guidance, use milk within 24 hours after it has completely thawed in the refrigerator. Once warmed or brought to room temperature, use it within two hours. Do not refreeze thawed milk. Use or discard leftovers within two hours after the baby finishes feeding.
Sources: CDC
Warm gently and check special situations
Microwaves can heat unevenly and should not be used to warm breast milk. Premature or unwell babies may need different instructions; follow the team caring for your baby.
Clearly distinguish fresh from thawed milk in the refrigerator. That avoids someone having to guess which time limit applies at the next feed.
Sources: NHS
When to seek support
Ask for advice about uncertain storage conditions, special medical needs or expressing difficulties. If your baby becomes unwell or feeds much less, do not wait to analyse storage records before seeking care.
Common questions
How long can breast milk stay in the refrigerator?
The CDC guidance used here allows freshly expressed milk up to four days at 4 °C / 40 °F or cooler. Milk fully thawed in the refrigerator has a shorter 24-hour limit. This applies to healthy full-term babies and appropriate storage conditions.
Does the 24-hour limit start when milk leaves the freezer?
The CDC refrigerator-thawing limit starts when the milk is completely thawed.
Can I refreeze thawed milk?
No. Previously thawed breast milk should not be refrozen.
Sources & further information
The sources for this guide are linked below. Examples and everyday tips help explain the topic; they are not a personal plan for your baby. Sources last accessed on 20 September 2026.
- CDC: Breast Milk Storage and Preparation
US public-health guidance; the storage table follows this source.
- NHS: Expressing and storing breast milk
UK public-health guidance.
- NHS: Dehydration
UK public-health guidance.
This guide was created with AI assistance and has not been medically reviewed. How we create our guides.
