A section 321 shipment cannot be consolidated, and all shipments must be manifested separately on the E-manifest using their own unique shipment control number (SCN). In addition, shipments filed under SEC321 must be sent to an ultimate consignee, not to a postal office or courier service. 

In these cases, using our shipment upload file (.csv) will be beneficial to reduce the time it takes to manually create shipments.

Attached is the ACE shipment upload form. It is also available in our Web Customs Portal under Document Download.