Cargo airlines are airlines mainly dedicated to the transport of cargo by air. Some cargo airlines are divisions or subsidiaries of larger passenger airlines. In 2018, airline cargo traffic represented 262,333 million tonne-kilometres with a 49.3% load factor: 52.1% for dedicated cargo operations, and 47.9% within mixed operations.

Air cargo is any property carried or to be carried in an aircraft. Air cargo comprises air freight, air express and airmail.