Yes, you can bring breast milk in a bottle on a plane in quantities greater than 3.4 ounces (100ml), as it is classified by the TSA as a "medically necessary liquid." This exemption applies regardless of whether your child is traveling with you at the time. When going through security, you must notify the officer that you are carrying breast milk and remove it from your carry-on bag for separate screening. TSA may use an X-ray or a "bottled liquid scanner" to verify the contents; if you prefer not to have the milk X-rayed, you have the right to request a manual inspection (swabbing or visual check). You are also allowed to bring frozen breast milk, as well as the ice packs, gel packs, and specialized coolers needed to keep it at a safe temperature. Even if the ice packs are partially melted or "slushy" at the time of screening, they are still permitted under this medical exemption. In 2026, most major airports have also added private "Mamava" or nursing suites past security to assist parents in managing their supply before boarding.