CBP (Customs and Border Protection)

US Customs and Border Protection is the federal agency that enforces import laws, classifies and assesses duty on incoming goods, collects tariffs and user fees, and clears (or holds) shipments at ports of entry. Every commercial import is filed with CBP electronically through its ACE system, and CBP is the body that liquidates entries, issues refunds, and processes protests. Example: when a courier advances your duty and bills you, it is remitting that duty to CBP on your behalf. It matters because CBP — not the seller or carrier — is the authority that determines what you owe, and the party you (or your broker) deal with to dispute or reclaim it.