A prepared formula bottle is good for up to 2 hours at room temperature if it has not yet been fed to the baby. Once the baby has started feeding from the bottle, any leftover formula must be used or discarded within 1 hour due to potential bacterial contamination from the baby's mouth. Prepared formula can also be stored safely in the refrigerator for up to 24 hours if not fed to the baby. After 24 hours in the fridge or beyond the 1-2 hour room temperature window, any unused formula should be discarded to avoid the risk of bacterial growth. For powdered formula containers, once opened, the powder should be used within 30 days and stored in a cool, dry place. Unopened formula containers can last until the expiration date stated by the manufacturer, typically around 18 months to 2 years. Key timelines for formula bottle safety:
- At room temperature (unfed): up to 2 hours
- After baby starts feeding: use or discard within 1 hour
- Refrigerated (unfed): up to 24 hours
- Opened powder container: use within 30 days
- Unopened formula: use before expiration date
These guidelines help ensure formula remains safe and nutritious for the baby.
