An airline alliance is an aviation industry arrangement between two or more airlines agreeing to cooperate on a substantial level. Alliances may provide marketing branding to facilitate travelers making inter-airline codeshare connections within countries. This branding may involve unified aircraft liveries of member aircraft.

An airline is a company that provides air transport services for traveling passengers and/or freight. Airlines use aircraft to supply these services and may form partnerships or alliances with other airlines for codeshare agreements, in which they both offer and operate the same flight. Generally, airline companies are recognized with an air operating certificate or license issued by a governmental aviation body. Airlines may be scheduled or charter operators.