Commerce at sea is priced by the cargo moved. Freight is the cargo carried by a ship, and also the charge paid to the carrier for transporting that cargo.

In bulk trades freight is often quoted per ton; in liner trades it may be per container or per revenue ton. Freight rates fluctuate with supply of ships and demand for transport. The contract of carriage defines when freight is earned and whether it is prepaid or payable at destination.

Disputes over freight arise from short-shipment, damage, or failure to complete the voyage. Understanding freight terms is basic to chartering and to cargo claims. For the shipowner, freight is the primary source of revenue that must cover operating costs and capital.

• Cargo carried by sea, or the charge for carrying it
• Quoted per ton, per container, or other units
• Subject to market fluctuations
• Defined by the contract of carriage