Confiscation of airport-purchased duty-free alcohol at transferring airports due to liquid-carrying restrictions is, unfortunately, quite common at airports around the world. Travelers making connecting flights should be careful about not purchasing duty-free liquor at their originating airports.
Instead, buying duty-free alcohol at the destination airport or at the stop immediately prior to the final destination or even onboard the final flight itself is a better and recommended course of action.
Specifically, travelers departing from international airports who arrive at a major US airport – such as LAX or JFK – where you are outside the secure facility when you leave customs will have to pass through security again for their connecting flight to their final destination. If you have space in your checked luggage for your duty-free purchase, you can quickly put it in your luggage before re-checking it for the domestic flight.
Otherwise, upon proceeding through domestic security, your purchase will be confiscated. Often the staff at duty-free shops will state that this will not happen. It does. A bottle of wine or other liquor, despite the duty-free bag and receipt will not be allowed as a carry-on on another flight unless you have not left the secured airport terminal area.
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Grounded by liquid laws