When is the certificate of origin for air transportation

This depends on which country you export by air. If you apply for the general certificate of origin Co, you can apply for it in advance before shipment, because the general customs clearance information of air cargo is always accompanied by the goods; if you handle the certificate of origin of free trade agreement, it is recommended to apply for the certificate of origin after shipment, because the flight number needs to be shown on the certificate of origin of free trade agreement And flight date, to avoid flight delay and lead to the wrong certificate information.