Customs Assigned Importer Number (CAIN)

A Customs Assigned Importer Number (CAIN) is a unique identification number assigned by U.S. Customs and Border Protection to an importer of record in the United States, which allows them to report imported goods to CBP for clearance.

The CAIN helps CBP identify the importer and track their imports over time.

It is required on all customs entry documents when filing an import shipment with U.S. Customs. It must be provided before any shipments can clear U.S. customs or receive duty-free treatment under certain trade agreements such as NAFTA or GSP programs.