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Glossary for the airline industry

Definitions and explanations of common terms in the airline industry


A set of fields in the Fare Manager Rules system for Combinations (Category 10) that provides access to and a summary of subcategory data.

secondary passenger

The Secondary Passenger Type Code is used to indicate the PTCs that may be further discounted by the presence of Categories 19-22 in the actual Fare By Rule tariff.

secondary portion of travel

A portion of travel of a fare component that is not determined as primary portion of travel.


In international fares, a portion of a journey covered by a single flight coupon. Also called segment.


In domestic US/CA fares, a portion of a journey covered by a single flight coupon. Also called sector.

Selling fare amount

The amount a passenger pays the agency (or consolidator) for the Negotiated Fare. Also called the Selling amount.

Selling updater

The person or organization who may update the Selling fare based on the Net fare and who makes the Negotiated Fare available for travel agents.


A continuous or related series. Mainly used in reference to the organization of data with categories in the FareManager Rules system.

Service Fees

ATPCO's suite of products that automates and centralizes the collection of ancillary fees for a wide range of secondary charges and services. The current suite of products includes Carrier-Imposed Fees, Ticketing Fees, Optional Services (including baggage allowance and charges), and Branded Fares.

Service Type Code

A code identifying the service for which a fee will be assessed. This code consists of a generic service code and a more specific Sub Code to further define the service. Optional Services uses the following six service types: flight-related service, ticket-related services, fare-related services, baggage allowance, baggage charges, and merchandise.


The process by which interline partners allocate revenue on a ticket where each carrier operated a coupon (that is, a sector or portion of the whole journey). 

sideline city

The city that appears second in a market city pair. Also called destination city.


Sale inside, ticketing inside; sold and ticketed in country of journey origin


Sale inside, ticketing outside; sold in country of journey origin and ticketed outside country of origin.


Sale outside, ticketing inside; sold outside country of journey origin and ticketed inside country of origin.


Sale outside, ticketing outside; sold and ticketed outside country of journey origin.


(CTA) Special Permission. Reference to the approval number given by a government for an application. See also approval number.


1. (interline accounting) Special Prorate Agreement. 2. (CTA) Special Permission Application. A submission to the Canadian government on behalf of a carrier requesting permission to action revisions on less than the governmentally required statutory notice.


1. Passengers who are holding tickets on standby fares that do not allow them to make reservations.

2. Passengers on a waiting list awaiting an available seat.

starting fare

A fare amount filed with ATPCO as a fare record or Fare By Rule that is used in the first step in the Negotiated Fares process to calculate or determine related fare amounts.