"Custom declaration" refers to a process where you declare or state the goods you are bringing into a country or taking out of it, which helps the government monitor and control trade, taxes, and other regulations. Full definition
There, you'll provide your fingerprints and your passport before filling out an electronic customs declaration card. (upgradedpoints.com)
A Mexican immigration form is required for each person and one Mexican customs declaration is required per family. (isla-mujeres.net)
Upon reaching the airport's immigration hall, members proceed to a Global Entry kiosk, insert their passport or U.S. permanent resident card, place their fingertips on the scanner for fingerprint verification, and complete an electronic customs declaration form. (frequentbusinesstraveler.com)