Why do we need custom declaration?
Why do we need custom declaration? A customs declaration is an official document that lists and gives details of goods that are being imported or exported. In legal terms, a customs declaration is the act whereby a person indicates the wish to place goods under a given customs procedure.
How does customs know if you have anything to declare?
On some occasions, when a traveler goes through US customs, there are electronic self-serve kiosks or paper forms with detailed customs questions about what you are carrying (currency, goods, food, etc.), and there are statements warning about penalties for not answering truthfully.