TSA officers may need to test the liquids for explosives or concealed prohibited items. Although not required, to expedite the screening process, it is recommended that formula and breast milk be transported in clear, translucent bottles and not plastic bags or pouches.

Giving milk to a toddler during travel requires a bit of strategy to navigate security and hygiene. Per TSA and global aviation rules in 2026, milk for toddlers is considered a "medically necessary liquid," meaning you can bring more than the standard 3.4oz limit through security. You should declare the milk to the officers at the start of screening; they may test the outside of the container or ask you to open it briefly. For the flight, many parents prefer shelf-stable milk boxes (UHT) that don't require refrigeration until opened. If you are using fresh milk, bring a small insulated bag with "gel packs" (which must be frozen solid when passing through security). Once onboard, you can ask flight attendants for a cup of warm water to soak the bottle in if your child prefers warm milk. Pro-tip: have your toddler drink during takeoff and landing, as the swallowing motion helps equalize ear pressure and prevents the pain caused by cabin pressure changes.