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Multilateral Interline System

No single airline, no matter the size, can serve every point in the world. This is why the multilateral interline system benefits all parties: 

Airlines are able to reach markets to which they do not operate directly and generate extra revenue in the process.  Market destinations can be added quickly and efficiently.

Consumers appreciate more choices and greater convenience, with worldwide travel options with one ticket, in one currency, and in one transaction with their luggage checked all the way through.
But the immunity from competition laws under which the system was operating is being scaled back in many parts of the world.

Establishing a new, convenient multilateral interline system that meets the competition concerns is crucial to continue offering passengers with the flexibility and convenience of interlining, and essential to the viability of air transport. 

Market-driven interlineable fares and online coordination - the way forward!

In order to respond to the future requirements of fare coordination, IATA has developed a mechanism based on the latest web-based technology, greatly increasing the speed, efficiency and accessibility of tariff coordination. It is based on two components:

  • The process: an internet-based voting mechanism, allowing carriers to propose and agree on changes to Flex fares formula and fare rules without having to meet face-to-face: e-Tariffs
  • The product: a market-driven interlineable fare, produced  automatically based on carrier fares: Flex Fares. This new system guarantees more transparent prices linked to market, while offering a cost and time-efficient process for airlines, and has been adopted for application worldwide.

In addition, an annual Composite Meeting provides worldwide standard rules and procedures in areas such as fare construction, baggage and currency handling. A twice-yearly Resolution Advisory Working Group (RADWG) is also conducted to give airlines and system providers the opportunity to work together on implementation. 

How to participate

Any active airline member of IATA may become a participant in Tariff Coordination (TC) either for Passenger, Cargo or for both.  When a carrier joins, it becomes an automatic voting member of the area e-Tariff conferences for which it has Third/Fourth Freedom rights and under certain conditions can choose to vote in other area conferences. TC members can also initiate or change agreements between meetings through the use of Mail Votes and filings, which enable them to keep up with the constant fluctuations of the market place.

No fee is required to be a Tariff Coordination member, for current and new members.

If you want to join tariff coordination or for more information, please contact IATA Passenger Tariffs at


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