Master bill of lading (MBL)

The shipping line issues the MBL to whoever contracted the space, usually a forwarder or NVOCC rather than the cargo owner. The forwarder's origin office typically appears as shipper and its destination office or agent as consignee. At destination, that agent surrenders the MBL, or relies on a telex release or sea waybill, to obtain the carrier's delivery order, and then releases the cargo to the importer against the house bill.

The MBL governs the relationship between carrier and forwarder: freight terms, the carrier's liability and the carrier's right to hold cargo until its freight is paid. The house bill of lading governs the relationship between forwarder and customer. A shipper normally never sees the MBL, and the freight terms and charges on the two documents can differ. When a shipper books directly with the line, the carrier's bill simply names the real parties and no house bill is needed.

In LCL and co-loading, the chain gets longer. For example, the carrier issues the MBL to a consolidator, the consolidator issues its own bill to the forwarder, and the forwarder issues the HBL to the exporter. Carrier tracking works on the MBL or container number, not the HBL number, because only the MBL exists in the carrier's systems. Forwarders record both numbers on every shipment so that status updates can be matched to customers.