Passengers traveling internationally into the United States with a connecting flight are allowed to pack more than 3.4 oz or 100 mL of liquids purchased in duty-free shops in their carryon baggage. These liquids must be secured in tamper-evident bags. Technological advances may allow passengers to keep these liquids in their carryon baggage, provided Transportation Security Officers at the checkpoint are able to clear and screen them.
Liquids that cannot be screened and cleared by TSA will not be allowed in a carryon bag. Passengers can pack these items in their checked baggage, if available, or forfeit them before entering the secure area of the airport. This may include liquids in opaque, ceramic, or metallic bottles, or other containers that cannot be effectively scanned.