How long can a tariff after receving goods can a tarriff be added?

A tariff is typically imposed at the time of importation and is applied to goods when they cross the border. Once goods have been received and cleared through customs, it's generally not possible to retroactively apply a tariff. However, if goods are still in customs or if there are changes in trade policies, tariffs may be adjusted or imposed before final clearance. Always check the specific regulations of the relevant customs authority for precise details.