Interlining and Codeshare Agreements Explained

Before we can discuss Interlining and Code Share agreements, you must first understand a few common terms used: 

Plating Carrier:

The term “plating” comes from the old days when paper tickets were used. First, Travel Agencies would be given a supply of paper tickets from each airline they were allowed to sell. As you can imagine, the larger agencies out there had safes filled with various airlines stock. The agencies would also have to do a sales report for each airline they did sales for. IATA later created the BSP – Bank Settlement Plan (Canada) and ARC – Airlines Reporting Corporation (USA) to bring some streamlining to the ticketing process. A standard and common set of paper tickets were  created (2 part, 4 part, MCO, etc) which were issued to travel agencies. The travel agency would then receive a heavy metal plate with the airlines emblem, name and IATA 3 digit code embossed on it. It was the size of a credit card. The agency could sell a ticket on, airline YY; they would take a generic 2 or 4 part ticket, the YY “plate” and put it in one of the manual validators. The ticket would be zipped through and then the agency would have a valid YY Airlines ticket. So, today when we hear or read about the “plating” carrier, this is where the term comes from.

Marketing Carrier:

This is the airline who is selling the ticket. There can be more than one marketing carrier for any true operating flight. I will explain this later, see Code Share Partners.

Operating Carrier:

This is the airline that is responsible for operating the flights. Or, if you’d like to think of it as “what airlines’ tail can I see sitting on the gate”. The operating carrier is often the same as the marketing carrier, however if you have traveled internationally, you often could find yourself sitting on a partner’s aircraft since codeshare agreement are often the best way for an airline to extend their reaches outside their normal serviced routes. See below for details.

Code Share partner:

A code share partner is one of many carriers that have agreed to share a route and publicize the route as their own flight. In this day and age we are all too familiar with the 3 big alliances around the globe. Star Alliance, SkyTeam and OneWorld. Each is a group of airlines that share their airline code “codeshare” on each other. This is a very unique way to appear to have more route coverage to the public without really having to have more aircraft or crew. It should be noted here that it is a legal requirement in most countries that all codeshares be disclosed to the traveling public. The traveller must be advised that “Ms. Smith, your flight to Upper Rubber Boot is actually being operated by Rubber Boot International Airlines”, yet Ms. Smith is actually talking to the reservations agent at Air Lower Slobodia.

Now that you have the basic understanding of some of the commonly used terms, I will now attempt to explain the difference between Interline and Codeshare agreements. Interline: Any sort of cooperation between airlines. That can take the form of an interline ticketing agreement, an interline baggage agreement or both.

An interline ticketing agreement is simply an agreement between two airlines to sell their flights on a common ticket. The airlines work out a pricing agreement to collect one single fare for two connecting flights and the division of moneys between the two carriers, often called a “prorate”. The airlines can then decide on who the marketing carrier will be. If both carriers wish to be the marketing carrier, the agreement is considered a bilateral interline agreement. In this case, both carriers will be the “plating” carrier whenever each sells the interline ticket. The interlining carriers then file the interlining route and fare with the various filling authorities such as OAG, ATPCO, Innovata etc. The back end accounting becomes a challenge and it is not to be taken lightly. Since your BSP will be collecting the funds and distributing these funds to the marketing carrier, a backend accounting distributor is often used to properly distribute the correct funds between the interlining carriers.

An interline baggage agreement is much simpler. An interline baggage agreement allows two airlines to accept and properly “through check” baggage onto the interlining airlines. The baggage information is collected at the passengers’ first check in point. The baggage tags are issued and communicated between the airlines and the airport authorities. This agreement is more convenient for the passengers as without the baggage interline agreement the passenger would be required to collect and re-check in their luggage at each connection point. Most carriers who have an interline ticketing agreement also have an interline baggage agreement; however it is not always the case. The interlining agreements can be negotiated separately.

Finally, what is the basic difference between CodeShare and Interline?

A codeshare partner simply means two or more carriers have agreed to be marketing carriers and sell a common route under their own flight number and name. The big buzzword around this is “One Stop Shop”. Go to one airline website or CRS or booking engine to complete and purchase the entire journey in one transaction. The operating carrier is often one of the marketing carriers. A very good example of this would be American Airlines flight AA051 from London Heathrow – LHR to Dallas Ft. Worth – DFW.

The actual operating carrier is American however, because AA is part of a global alliance the flight has 8 (yes eight!) marketing carrier flight numbers attached to it. American flight AA051 is operated AND marketed as AA051 as well as BA1504; IB4193; QR4913; AY5753; GF6651; LY8029 and MH9395. I have seen some operating carriers that are not even a marketing carrier. When I first started traveling, I sometimes stopped at my published gate and saw that it was a completely different airline and flight number scheduled to depart. I would run back to the FIDS to recheck my gate, only to see the FIDS flipping from codeshare partner to codeshare partner to codeshare partner for the actual operating flight.

A codeshare agreement usually requires an interline agreement and allows the marketing carrier to publish an operating carriers flights within their system and sales channels as their own.

In case you are wondering, through boarding passes are separate from interline agreements and do not necessarily mean there is an interlining agreement between the airlines. This is a completely different IATA process called IATCI (Inter Airline Through Check-In). The transfer of baggage information between the carriers is an IATA process called BRS (Baggage Reconciliation System). Both of these processes involve messages shooting back and forth between systems allowing each airlines CRS to “talk” to the other airlines CRS.

In the end, if the airline can make it easier for the customer to travel on their airline, they will indeed gain market share. A share in a large market is better than no share at all.